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goodgrouper
09-11-2015, 12:28 AM
How often can you find a load in the tunnel one day and have it work just as well another day? I'm having a hard time getting a load to shoot good twice in one day and now I can't blame it on the wind or temp changes!:eek::confused:

Dusty Stevens
09-11-2015, 01:43 AM
Tunnels are weird weird animals. Most get out once the novelty runs out. Call gene beggs and ask him whats going on he is the longest lasting tunnel rat i know of and ill bet he knows

Wilbur
09-11-2015, 10:03 AM
Yep, Gene Beggs!

Perhaps he will comment here....Gene has a really nice tunnel setup and knows quite a bit otherwise. I actually flew to Texas to visit with Gene and his tunnel some years ago. Had a great time and was truly impressed with everything I saw...including Gene. :)

Wilbur
09-11-2015, 11:23 AM
I was washing the dishes and realized referencing Gene might not have been the best I could do here.

A tunnel is involved but that's the only thing different. The same thing can happen outside a tunnel and the question is tough at best. Keith Gantt and I used to go to the Chattanooga Rifle Club to get ready for a match. We always shot poorly (.3xx or worse), but when we went to the match we did pretty good. I really don't know why we shot there but we did. What I'm saying here is that where you shoot has a bearing on how you shoot and sometimes you can't fix it.

Gene Beggs
09-11-2015, 12:38 PM
Yep, Gene Beggs!

Perhaps he will comment here....Gene has a really nice tunnel setup and knows quite a bit otherwise. I actually flew to Texas to visit with Gene and his tunnel some years ago. Had a great time and was truly impressed with everything I saw...including Gene. :)


Wilbur, thanks for the kind words. I sure enjoyed your visit to the West Texas tunnel. We had a great time; didn't we?

Folks, Wilbur loves Starbuck's coffee and good steaks. My kinda' guy! :D

Gene Beggs

MilGunsmith
09-11-2015, 01:48 PM
What size tunnel? We have two 16'x16'x100yards, one 16'x16'x300yards, and one 7'x7'x50yards. Could you be getting shock wave bouncing off the walls?

goodgrouper
09-11-2015, 03:37 PM
Thanks for the replies thus far guys.

The tunnel is 6' roundx100 yards. It is well ventilated and has a very slight draw draft. No mirage, steady afternoon temps. First thing I did was check for shockwave influence and I would have to say there is zero. I have shot several groups in it that were so tight that I could take the target, lay it flat, insert a bullet into the hole, and the paper would hold the weight of the bullet. I don't think I could shoot that small if the tunnel had problems. I think what I'm discovering is something I've feared for the last 4 years........the gun is not consistent day to day with any load. I have taken several 6.5x284 wildcats, one 6.5x47, and one 338 Edge into the tunnel on separate occasions and had them shoot the same load great every time, and velocities were within 3 fps each time. I put my 6ppc in there and suddenly the place gets overrun with voodoo mysticism.

I used to win a fair amount of wood with my old "snake" gun, and the world made sense. Newtons Laws balanced out with Murphy's Laws and things were predictable. Now that I've got this "bear" gun, it feels like I've taken a nose dive down the rabbit hole and the Cheshire Cat is loading my ammo........

j mckinnie
09-11-2015, 05:54 PM
a glue in .coz when the glue is bad they do that weird stuff

Gene Beggs
09-12-2015, 03:25 PM
How often can you find a load in the tunnel one day and have it work just as well another day? I'm having a hard time getting a load to shoot good twice in one day and now I can't blame it on the wind or temp changes!:eek::confused:


This is a deep subject and I'm trying to decide how best to respond. :)

Later,

Gene Beggs

Pete Wass
09-12-2015, 10:18 PM
Yes, YEs, YES! Thank you Lou. I started a thread earlier in wk titled "Second Match Curse?" Unfortunately it went away during (or before?) the recent rehab on the Forum. At last weekends IBS VT State Score Match I did OK at 100 yd and was still clean after match 1 at 200. A fellow competitor complimented me to which I answered, I still had to get past the 2nd and 3rd match "curse." If I drop points it is almost always on one of those two. And of course on match 2 (which was just miserable!) I lost one. But then on the next match I posted a 50-4X! So the question is . . . WHY?! (sorry for shouting . . .) What's so different about match 2 and sometimes 3? Targets 4 and 5 typically go well. Last week's equipment: BAT 6 PPC, Krieger 1:13 1/2" twist bbl with 800 rnds, new Weaver 36X XR scope, Lap 220 Russ Brass, IMR 8208 powder, Bart's 68 gr Ultras, Wolf SRM primers, Farley Co-ax II front rest, Protektor rear bag. Observations, ideas, comments are welcome.

Zdog (that's Zee-dog! Chris Mitchell)

The 6PPC. Solution - - - - - - Drum Roll Please - - - - - - -- 30 BR :) Sorry, I couldn't resist Chris.

Pete, in California.

mks
09-13-2015, 11:57 AM
Lou says his guns won't shoot from 11-1, then his posts disappear. It like something out of the X-Files.:eek:

Wilbur
09-13-2015, 12:17 PM
Lou does that....don't know why but he does.

Wilbur
09-13-2015, 12:39 PM
I think you've concluded the correct answer...it's not a winning rifle. Sure, you could keep trying stuff like different powders, fat bullets, etc... but you would be ahead if you just gave up on it.


Just an opinion as you're smarter about this stuff than I am...

By the way - have you tried fat bullets? :)

Tim Singleton
09-13-2015, 01:15 PM
Have you screwed on another barrel to see if it exhibits the same lack of repeatability?

Not shooting in a tunnel but I went through 4 barrels last year before I got to one that would repeat a small group. Or in other words give a good solid aggregate for an entire day.

I'm still waiting to hear Gene.'s response to this question. My first knee jerk is the tunnel would help you qualify barrels much faster than outside. Then one would have to see if it would shoot in the wind
Without knowing more about your procedure I'm just guessing.

Gene Beggs
09-13-2015, 03:24 PM
I don't know where to begin. :o Excuse me for a moment while I go get another cup of strong, black coffee. :cool:

Will the best tunnel ever built enable one to shoot one zero after another, all day long? NO!

Is a tunnel really an asset to a benchrester for testing rifles, shooters and components? YES!

Are there any mysteries about tunnel operation that experienced tunnel rats have known about for years but thus far have been unable to explain? YES, but now I believe I know what they are; RING VORTICES and SLOW MIRAGE! :eek:


Ring vortices? Yep, you've seen them many times, usually when a smoker blows a smoke ring.

A well built tunnel with complete control of the airflow eliminates dispersion caused by wind but also confines anything that is blasted down the tube when the rifle is fired; i.e., hot gases, wake turbulence created by the supersonic projectile and most importantly, ring vortices created by muzzle blast. :eek:

The tunnel blocks wind but also confines vortices that continue rotating for quite some time directly in the path of following shots. You cannot see them and they do not show up in the fixed reference scope. Same thing happens outdoors in dead calm conditions. And of course, with every shot fired, especially in rapid succession, the more likely following shots will encounter turbulence. So how do you deal with this monster? :eek:

Well, outdoors, if you have time, you can wait for a slight crosswind to drift them out of your way but lacking that you'll just have to shoot and take your chances. Even the greatest shooters in the world will say, "There are times when you just can't explain a flier."

In the tunnel where there are no time restrictions, the air should be completely evacuated with the exhaust fan on high blower for two to three minutes. After the fan speed is reduced to low and the fixed reference scope indicates that the target image has settled down to where it really is, you can begin your group. I don't always evacuate the tunnel between every group, especially if I'm shooting alone. I'm so damn slow it has plenty of time to settle down while I clean or take a break. :rolleyes:

This is good enough for starters. Any questions?

Later,

Gene Beggs

vtmarmot
09-13-2015, 10:13 PM
I've been reading Vaughn's "Accuracy Facts" a page or two at a time with my breakfast muffin. Friday, I read about ring vorteces and also variable blast patterns caused by bullet canting. If you have any cant at all it seems like you'd get variable blast effects coming off the walls of a 6 foot round tunnel.

mks
09-13-2015, 10:31 PM
I've been reading Vaughn's "Accuracy Facts" a page or two at a time with my breakfast muffin. Friday, I read about ring vorteces and also variable blast patterns caused by bullet canting. If you have any cant at all it seems like you'd get variable blast effects coming off the walls of a 6 foot round tunnel.

Remember that for a supersonic projectile, the projectile moves faster than any effects that are bounced off the walls. It is the effects left by the previous bullet that are a concern, and they can be variable for a number of reasons.

Dave B
09-16-2015, 08:44 PM
Call me sometime and I'll tell you more about Lou's tunnel. I doubt he has ever regretted it. Sure it was extremely pricey.Hundreds (yes, with a S) of thousands. I use to spend alot of time in Brownings tunnel in Morgan Utah, Lou[s makes theirs junk. It truly will do anything. Temperature and humidity controled from the reloading area to bullet impact, 24 hours aday.. Video with bullet speed recorded on every shot. The bullets travel down a 4 foot square cement tube which is accoustic lined the entire way. Take a few day and come down and we'll go down for a few days.
Dave B

StaMoly Jackets
09-18-2015, 06:07 PM
There is a group of shooters in Southern Maryland that have been testing in an old 400' long Chicken house. We call it "The Hen House". I have extensively tested bullets, jackets powders, barrels etc. The group that operates it has shot way more than I have in it. I will see if they will chirp up and discuss some of the findings as well.

This indoor location has 7 super sturdy wood benches spaced normally, a loading area and heat for the loading area during winter. There are mirage days when there appears to be a big temperature difference between the ground and air temperature. But mostly, the indoor range has the most crisp, clear target view I have ever seen. The facility is about 50 feet wide and a 10-12' ceiling. I have seen a particular young shooter shoot multiple zeros back to back and over and over again. I have seen this particular gun win the 2014 Score nationals tuned in this facility. I have seen this same young shooter do very well using the indoor tune with his PPC at Weikerts Boop Memorial shoot where he finished 2nd in the two gun to Larry Costa. Its safe to say that this facility rarely has the gremlins associated with traditional small volume tunnels (this volume is 400'x50'x12').

I will say this with the PPC. There is rarely a day that the PPC will stay in tune. Great barrels are more forgiving. Great bullets seem to make the biggest difference. This is with both V133 and LT32. The PPC might go 3 hrs or 2 hours.....but you'd better be ready to change it to keep shooting mid ones. I will say that if there was ever and indoor match at this location, all of the regular shooters would grab their 30BR's. The 30 BR will shoot the same load from 30F-95F day in day out. The 30BR rarely needs changed. I have personally witnessed 4 x 5 shot zero's in a row with one particular 30BR. Each time it has been done with Allie Eubers 117gr bullet.

To answer the original question. It is rare to find a 6PPC that will stay in tune (sub 0.200") each and every day. Furthermore, it will change after 2-4 hours and you better change it or the same load will shoot a .350".

A Novel could be started documenting what is being found in this facility. I will keep contributing as time allows.

Jeff Peinhardt
StaMoly Jackets

goodgrouper
09-19-2015, 12:10 AM
I don't know where to begin. :o Excuse me for a moment while I go get another cup of strong, black coffee. :cool:

Will the best tunnel ever built enable one to shoot one zero after another, all day long? NO!

Is a tunnel really an asset to a benchrester for testing rifles, shooters and components? YES!

Are there any mysteries about tunnel operation that experienced tunnel rats have known about for years but thus far have been unable to explain? YES, but now I believe I know what they are; RING VORTICES and SLOW MIRAGE! :eek:


Ring vortices? Yep, you've seen them many times, usually when a smoker blows a smoke ring.

A well built tunnel with complete control of the airflow eliminates dispersion caused by wind but also confines anything that is blasted down the tube when the rifle is fired; i.e., hot gases, wake turbulence created by the supersonic projectile and most importantly, ring vortices created by muzzle blast. :eek:

The tunnel blocks wind but also confines vortices that continue rotating for quite some time directly in the path of following shots. You cannot see them and they do not show up in the fixed reference scope. Same thing happens outdoors in dead calm conditions. And of course, with every shot fired, especially in rapid succession, the more likely following shots will encounter turbulence. So how do you deal with this monster? :eek:

Well, outdoors, if you have time, you can wait for a slight crosswind to drift them out of your way but lacking that you'll just have to shoot and take your chances. Even the greatest shooters in the world will say, "There are times when you just can't explain a flier."

In the tunnel where there are no time restrictions, the air should be completely evacuated with the exhaust fan on high blower for two to three minutes. After the fan speed is reduced to low and the fixed reference scope indicates that the target image has settled down to where it really is, you can begin your group. I don't always evacuate the tunnel between every group, especially if I'm shooting alone. I'm so damn slow it has plenty of time to settle down while I clean or take a break. :rolleyes:

This is good enough for starters. Any questions?

Later,

Gene Beggs

Thanks Gene. I was hoping you'd post. Good food for thought. I can see how those vortices could cause errant fliers. But what I'm seeing are loads that appear to be in tune, then go away too soon for them to be competitive in a match where you have to wait 30 or 40 minutes before you get back up to the line. I need more time in the tunnel to try a few more things, but honestly, I can't bring myself to do it right now. I'm just too disgusted with the current status of the industry/sport as of late, and the thought of going in there and getting frustrated yet again just doesn't sound fun anymore:(

goodgrouper
09-19-2015, 12:13 AM
Call me sometime and I'll tell you more about Lou's tunnel. I doubt he has ever regretted it. Sure it was extremely pricey.Hundreds (yes, with a S) of thousands. I use to spend alot of time in Brownings tunnel in Morgan Utah, Lou[s makes theirs junk. It truly will do anything. Temperature and humidity controled from the reloading area to bullet impact, 24 hours aday.. Video with bullet speed recorded on every shot. The bullets travel down a 4 foot square cement tube which is accoustic lined the entire way. Take a few day and come down and we'll go down for a few days.
Dave B

Thanks for the offer Dave. Maybe this winter I'll come down and pick you up. I don't think my tunnel is the problem, but it would be good to get your's and Lou's advice on the course of action for my future in this wicked game. Maybe the three of us will be able to come to some idea of what to do....

goodgrouper
09-19-2015, 12:22 AM
There is a group of shooters in Southern Maryland that have been testing in an old 400' long Chicken house. We call it "The Hen House". I have extensively tested bullets, jackets powders, barrels etc. The group that operates it has shot way more than I have in it. I will see if they will chirp up and discuss some of the findings as well.

This indoor location has 7 super sturdy wood benches spaced normally, a loading area and heat for the loading area during winter. There are mirage days when there appears to be a big temperature difference between the ground and air temperature. But mostly, the indoor range has the most crisp, clear target view I have ever seen. The facility is about 50 feet wide and a 10-12' ceiling. I have seen a particular young shooter shoot multiple zeros back to back and over and over again. I have seen this particular gun win the 2014 Score nationals tuned in this facility. I have seen this same young shooter do very well using the indoor tune with his PPC at Weikerts Boop Memorial shoot where he finished 2nd in the two gun to Larry Costa. Its safe to say that this facility rarely has the gremlins associated with traditional small volume tunnels (this volume is 400'x50'x12').

I will say this with the PPC. There is rarely a day that the PPC will stay in tune. Great barrels are more forgiving. Great bullets seem to make the biggest difference. This is with both V133 and LT32. The PPC might go 3 hrs or 2 hours.....but you'd better be ready to change it to keep shooting mid ones. I will say that if there was ever and indoor match at this location, all of the regular shooters would grab their 30BR's. The 30 BR will shoot the same load from 30F-95F day in day out. The 30BR rarely needs changed. I have personally witnessed 4 x 5 shot zero's in a row with one particular 30BR. Each time it has been done with Allie Eubers 117gr bullet.

To answer the original question. It is rare to find a 6PPC that will stay in tune (sub 0.200") each and every day. Furthermore, it will change after 2-4 hours and you better change it or the same load will shoot a .350".

A Novel could be started documenting what is being found in this facility. I will keep contributing as time allows.

Jeff Peinhardt
StaMoly Jackets


Very interesting and thank you for posting. It's nice to hear that someone else has seen the same things I've been getting. In regards to the 30br, I think you may have sold me. I was actually drawing up a blueprint for a reamer two years ago for a 30, and fully intended on dumping the ppc entirely. But then the bullet/jacket crunch hit and I didn't want to wait 9 months to get a box of 30 cal bullets. I still have my brass and print, and recoil won't bother me a bit since I shoot magnums all the time. Perhaps it's time to jump ship now that the bullets are getting a little easier to find....

goodgrouper
09-19-2015, 02:52 AM
a glue in .coz when the glue is bad they do that weird stuff

Nope, it's a bolt in.

goodgrouper
09-19-2015, 03:01 AM
I think you've concluded the correct answer...it's not a winning rifle. Sure, you could keep trying stuff like different powders, fat bullets, etc... but you would be ahead if you just gave up on it.


Just an opinion as you're smarter about this stuff than I am...

By the way - have you tried fat bullets? :)

I think you're the smart one Wilbur! You concluded the probable right answer immediately!

The question is, what haven't I tried in it???:rolleyes:

goodgrouper
09-19-2015, 03:17 AM
Have you screwed on another barrel to see if it exhibits the same lack of repeatability?

Not shooting in a tunnel but I went through 4 barrels last year before I got to one that would repeat a small group. Or in other words give a good solid aggregate for an entire day.

I'm still waiting to hear Gene.'s response to this question. My first knee jerk is the tunnel would help you qualify barrels much faster than outside. Then one would have to see if it would shoot in the wind
Without knowing more about your procedure I'm just guessing.


I have only shot one barrel in the tunnel so far. It is a pre-'09 barrel. Shows signs of being a very capable barrel.....once in awhile! Maybe it's just tf-ing me. But buying a new barrel ain't any more of a guarantee. It's like you say, buy half a dozen to get one that might be decent. What a crap shoot! Didn't used to be that way........
If I'd have known what was going to happen to Crucible Steel and the current state of the steel industry, I'd have gotten four or five credit cards and maxed them all out on barrels in '07. But hindsight is always 20/20!

Wilbur
09-19-2015, 02:42 PM
Nope, it's a bolt in.

Well hell! There's your problem!! :)

Gene Beggs
09-19-2015, 06:28 PM
When you have a barrel that is extremely sensitive to tune, you are very likely tuned to the 'bottom stop' of the barrel's vibration cycle. :eek: Let me explain. :cool:

It is now widely understood that bullet exit timing relative to where the muzzle is pointing is critical for best accuracy and widest tune window. As the barrel vibrates and the muzzle goes through its 'whip cycle' it comes to a complete stop at the top and bottom. There are two in-tune sweet spots; one just before the top stop and another just after the bottom stop. Both sweet spots occur as the muzzle is on the way up, providing what is known as 'positive compensation' for variations in muzzle velocity; slow shots exit when the muzzle is pointed higher, faster shots exit when the muzzle is pointed lower. The rifle will shoot well at either spot but the upper sweet spot, just before the barrel reaches the apex of its swing is much more forgiving and the rifle stays in tune through greater changes in atmospheric conditions. "So how in 'ell do you tell which is which?" :mad: Good question; I'll try to explain.

In his book, "Extreme Rifle Accuracy" Mike Ratigan describes a very critical, sensitive tune as being like trying to 'balance razor blades." Now you know what he meant. :cool:

Understand that if we were to start tuning at the lowest practical load of let's say 27 grains N133 for the 6ppc, we would encounter an 'in-tune' condition every 120 fps as we gradually increase the charge by .3 grain increments up to a maximum of around 30.2 grains. Expressed in grains of powder the sweet spots occur every 1.2 grains. Some rifles shoot terrific at 27 grains but rarely are we so lucky to be right in tune starting out, but even if we start out completely out of tune which is indicated by two bullet holes of vertical at 100 yards, we can't be more than .6 grains in either direction out of tune! :eek: Huh? :eek: Yep, it's true! :cool:

No matter where you are between 27 grains and 30.2, you can't be more than .6 grains from either the top stop or bottom stop. If the rifle shows in tune at the particular time, (no vertical) go to the record! :p Sure, you do not yet know whether you are tuned to the top or the bottom but who cares; conditions aren't going to change during the 7 minutes you have to shoot five record shots. If the tune proves to be very sensitive we can easily reverse it and jump to the top stop by increasing the load by 1.2 grains. So let's try some examples: Let's say 6ppc, N133 Panda Sporter, good barrel and good bullets seated just off the lands.( all BR rifles in use today behave the same way.)

Start at 27 grains. 3 shot test groups show one bullet hole of vertical indicating the rifle is only .3 grains from one or the other sweet spots. But should we go UP .3 grains or DOWN .3 ? Simple. :cool: Go either way and it will tell you what you want to know. If you go UP .3 and the group opens up to two bullet holes of vertical, you know you went the wrong way and the rifle is now completely out of tune. :mad: Go back where you were and then go DOWN .3 and the vertical should disappear. The rifle is now in tune under those specific atmospheric conditions with 26.7 grains. Most shooters don't like to shoot down in the first window so let's go up 1.2 grains to 27.9 and see what happens.

Okay, second match of the day. We notice temp has increased about ten degrees from the early morning low of 60 so we know the rifle is not likely to be in tune, but who cares; we're going to re-tune anyway. We want to shoot up in the 27.9 to 28.0 grain range so lets start out with 28 grains. A three shot test group shows no vertical! :eek: Well I'll be darned. :rolleyes: I guess we just jumped from the bottom stop to the wider, more forgiving top stop. :D Great! Go to the record! :D

Now, for match three, temp has increased to 75 degrees but we don't change the load hoping that positive compensation will take care of us. The record group was good with only one bullet hole of vertical so we know the 15 degree increase in temp is beginning to show so we lower the charge from 28 grains to 27.7 for match four.

Match four. Temp is now 80 degrees so we reduce the charge to 27.4 just to be safe. Sure enough, the three shot test group shows no vertical so our calculations were correct. If temp remains the same or doesn't increase by more than five degrees we know we are safe to go to the line for match five with the same load.

Make sense? Questions?

Hope Keith Sharp (MKS) will join in. He explains things so much better than I do. :o

Later,

Gene Beggs

mwezell
09-19-2015, 08:22 PM
When you have a barrel that is extremely sensitive to tune, you are very likely tuned to the 'bottom stop' of the barrel's vibration cycle. :eek: Let me explain. :cool:

It is now widely understood that bullet exit timing relative to where the muzzle is pointing is critical for best accuracy and widest tune window. As the barrel vibrates and the muzzle goes through its 'whip cycle' it comes to a complete stop at the top and bottom. There are two in-tune sweet spots; one just before the top stop and another just after the bottom stop. Both sweet spots occur as the muzzle is on the way up, providing what is known as 'positive compensation' for variations in muzzle velocity; slow shots exit when the muzzle is pointed higher, faster shots exit when the muzzle is pointed lower. The rifle will shoot well at either spot but the upper sweet spot, just before the barrel reaches the apex of its swing is much more forgiving and the rifle stays in tune through greater changes in atmospheric conditions. "So how in 'ell do you tell which is which?" :mad: Good question; I'll try to explain.

In his book, "Extreme Rifle Accuracy" Mike Ratigan describes a very critical, sensitive tune as being like trying to 'balance razor blades." Now you know what he meant. :cool:

Understand that if we were to start tuning at the lowest practical load of let's say 27 grains N133 for the 6ppc, we would encounter an 'in-tune' condition every 120 fps as we gradually increase the charge by .3 grain increments up to a maximum of around 30.2 grains. Expressed in grains of powder the sweet spots occur every 1.2 grains. Some rifles shoot terrific at 27 grains but rarely are we so lucky to be right in tune starting out, but even if we start out completely out of tune which is indicated by two bullet holes of vertical at 100 yards, we can't be more than .6 grains in either direction out of tune! :eek: Huh? :eek: Yep, it's true! :cool:

No matter where you are between 27 grains and 30.2, you can't be more than .6 grains from either the top stop or bottom stop. If the rifle shows in tune at the particular time, (no vertical) go to the record! :p Sure, you do not yet know whether you are tuned to the top or the bottom but who cares; conditions aren't going to change during the 7 minutes you have to shoot five record shots. If the tune proves to be very sensitive we can easily reverse it and jump to the top stop by increasing the load by 1.2 grains. So let's try some examples: Let's say 6ppc, N133 Panda Sporter, good barrel and good bullets seated just off the lands.( all BR rifles in use today behave the same way.)

Start at 27 grains. 3 shot test groups show one bullet hole of vertical indicating the rifle is only .3 grains from one or the other sweet spots. But should we go UP .3 grains or DOWN .3 ? Simple. :cool: Go either way and it will tell you what you want to know. If you go UP .3 and the group opens up to two bullet holes of vertical, you know you went the wrong way and the rifle is now completely out of tune. :mad: Go back where you were and then go DOWN .3 and the vertical should disappear. The rifle is now in tune under those specific atmospheric conditions with 26.7 grains. Most shooters don't like to shoot down in the first window so let's go up 1.2 grains to 27.9 and see what happens.

Okay, second match of the day. We notice temp has increased about ten degrees from the early morning low of 60 so we know the rifle is not likely to be in tune, but who cares; we're going to re-tune anyway. We want to shoot up in the 27.9 to 28.0 grain range so lets start out with 28 grains. A three shot test group shows no vertical! :eek: Well I'll be darned. :rolleyes: I guess we just jumped from the bottom stop to the wider, more forgiving top stop. :D Great! Go to the record! :D

Now, for match three, temp has increased to 75 degrees but we don't change the load hoping that positive compensation will take care of us. The record group was good with only one bullet hole of vertical so we know the 15 degree increase in temp is beginning to show so we lower the charge from 28 grains to 27.7 for match four.

Match four. Temp is now 80 degrees so we reduce the charge to 27.4 just to be safe. Sure enough, the three shot test group shows no vertical so our calculations were correct. If temp remains the same or doesn't increase by more than five degrees we know we are safe to go to the line for match five with the same load.

Make sense? Questions?

Hope Keith Sharp (MKS) will join in. He explains things so much better than I do. :o

Later,

Gene Beggs
Now tell em' about tuners, Gene.

http://www.reactiongifs.com/wp-content/uploads/2011/05/tumblr_ljh0puClWT1qfkt17.gif

Gene Beggs
09-19-2015, 11:40 PM
[QUOTE=mwezell;764494]Now tell em' about tuners, Gene.


Yep, I was saving that for last, Mike. After comparing how complicated, time consuming and frustrating tuning with the powder charge is, I hope to convince the skeptics how easy it is to tune with the tuner. :cool:

You know it, I know it and many others know it but might be keeping it to themselves. :rolleyes: But maybe, just maybe this will help someone that is still in the dark about tuners. :) Stay with us and help me out especially if I say something that's wrong. :o

Later,

Gene Beggs

HFV
09-28-2015, 11:37 AM
I was washing the dishes and realized referencing Gene might not have been the best I could do here.

A tunnel is involved but that's the only thing different. The same thing can happen outside a tunnel and the question is tough at best. Keith Gantt and I used to go to the Chattanooga Rifle Club to get ready for a match. We always shot poorly (.3xx or worse), but when we went to the match we did pretty good. I really don't know why we shot there but we did. What I'm saying here is that where you shoot has a bearing on how you shoot and sometimes you can't fix it.

It was those benches @ Chattanooga,,, just wasn't able to shoot small there.. I went as a guest twice and almost sold a good rifle.

Hunter
09-28-2015, 01:12 PM
The rifle is now in tune under those specific atmospheric conditions with 26.7 grains. Most shooters don't like to shoot down in the first window so let's go up 1.2 grains to 27.9 and see what happens.

Okay, second match of the day. We notice temp has increased about ten degrees from the early morning low of 60 so we know the rifle is not likely to be in tune, but who cares; we're going to re-tune anyway. We want to shoot up in the 27.9 to 28.0 grain range so lets start out with 28 grains. A three shot test group shows no vertical! :eek: Well I'll be darned. :rolleyes: I guess we just jumped from the bottom stop to the wider, more forgiving top stop. :D Great! Go to the record! :D

...

Make sense? Questions?

Mr. Beggs, yes, I've got a question. IIRC, at one time you said to decrease powder .3 gr for every 5 deg. increase in temp. In the example above, you were in tune at 60 deg. w/ 26.7 gr, then temp went up 10 deg. which would suggest dropping to 26.1 gr to stay in tune at that "sweet spot." Since you want to shoot at the other "sweet spot" it seems that you should go to 27.3 gr; however, your three-shot test group shows you in tune at 28 gr. -- a difference of .7 gr, or enough to be almost "completely out of tune." What am I missing?

Gene Beggs
09-28-2015, 03:16 PM
Mr. Beggs, yes, I've got a question. IIRC, at one time you said to decrease powder .3 gr for every 5 deg. increase in temp. In the example above, you were in tune at 60 deg. w/ 26.7 gr, then temp went up 10 deg. which would suggest dropping to 26.1 gr to stay in tune at that "sweet spot." Since you want to shoot at the other "sweet spot" it seems that you should go to 27.3 gr; however, your three-shot test group shows you in tune at 28 gr. -- a difference of .7 gr, or enough to be almost "completely out of tune." What am I missing?


Hunter

You are a man who pays very close attention to everything said and you are absolutely correct.

What are you missing? Nothing! :o


I used a poor choice of numbers in the example above probably because I've been working with a shooter in the tunnel that prefers to shoot at the extreme lower window of the 6ppc. We were using XBR powder at 26.8 grains to start with. The numbers got mixed up in my feeble mind. :o

In 100-200 yard group shooting with the 6ppc, there are many powders in use but the standard by which others are measured is Vit., N-133. Some are faster burning and this will affect how much change it takes to compensate for changes in atmospheric conditions; mainly temp increases. The recommended adjustment of .3 grains per five degrees temp change was worked out over several years of simply observing what it took to keep the rifle in tune as the day warmed up. Nothing in benchrest is absolute and the numbers we use to tune are only close approximations to get us in the ball park. Scales and powder measures vary by around plus or minus .2 grains and some powders burn a little faster than others so trying to predetermine exactly what the load should be is futile. The only sure way of knowing what the load should be is to listen to what the rifle is telling you with the test groups it prints on the sighter;

* Little or no vertical? 'I'm in tune, go to the record.'

* One bullet hole of vertical? 'I'm about .3 grains out of tune, one way or the other. Which way? Go either up or down and I'll tell you by showing either no vertical or two bullet holes in which case you went the wrong way. :rolleyes:

* Two bullet holes of vertical? 'I'm completely out of tune. Go up or down around .6 grains or so and I should be reasonably in tune at either the top or bottom stop of the muzzle swing. But which one? Beats the 'ell outta' me! :rolleyes::p:o

"Damn, I knew I shouda' bought one of those Beggs tuners years ago, then I wouldn't have to be carrying all these different loads to the line. :mad: I could simply make an adjustment to the tuner at the line and never have to change the load, EVER. :rolleyes:

Yep, it's true, believe it or not. Getting the rifle in tune by adjusting the tuner is just like adjusting the focus on an old Leupold 36 target scope. How do you get one of those beautiful old 36's in focus? Why, you loosen the lock ring and rotate the focus ring in one direction or the other till the target image is clear. :) ""But what if you go the wrong way?? Simple, if the image get worse, you went the wrong way; go back the other way till it gets clear.

Now,,, what about focusing a tuner/barrel??? Same way as focusing the scope. With a Beggs tuner which is 28 tpi thread, you cannot possibly be more than a half turn out of tune. Shoot a 3 shot test group on the sighter. The rifle will tell you one of three things;

1. Little or no vertical; I'm in tune. Go to the record.

2. About one bullet hole of vertical; I'm only about a quarter turn out of tune. But which way? Reach up there and give the tuner a quarter turn in either direction. If the next test group increases to two bullet holes of vertical, you went the wrong way. (That's usually what happens to me.) Go back where you were and make a quarter turn in the other direction and you'll be in tune. Go to the record.

3. Two bullet holes of vertical; fully out of tune. A half turn in either direction will put the rifle in tune. But will I be tuned to the top or bottom stop? Who cares? In tune is in tune. :rolleyes:

Hope this helps. For a while, I was beginning to think no one was even listening and didn't care to discuss this further.

Later

Gene Beggs

mwezell
09-28-2015, 04:02 PM
Hunter

You are a man who pays very close attention to everything said and you are absolutely correct.

What are you missing? Nothing! :o


I used a poor choice of numbers in the example above probably because I've been working with a shooter in the tunnel that prefers to shoot at the extreme lower window of the 6ppc. We were using XBR powder at 26.8 grains to start with. The numbers got mixed up in my feeble mind. :o

In 100-200 yard group shooting with the 6ppc, there are many powders in use but the standard by which others are measured is Vit., N-133. Some are faster burning and this will affect how much change it takes to compensate for changes in atmospheric conditions; mainly temp increases. The recommended adjustment of .3 grains per five degrees temp change was worked out over several years of simply observing what it took to keep the rifle in tune as the day warmed up. Nothing in benchrest is absolute and the numbers we use to tune are only close approximations to get us in the ball park. Scales and powder measures vary by around plus or minus .2 grains and some powders burn a little faster than others so trying to predetermine exactly what the load should be is futile. The only sure way of knowing what the load should be is to listen to what the rifle is telling you with the test groups it prints on the sighter;

* Little or no vertical? 'I'm in tune, go to the record.'

* One bullet hole of vertical? 'I'm about .3 grains out of tune, one way or the other. Which way? Go either up or down and I'll tell you by showing either no vertical or two bullet holes in which case you went the wrong way. :rolleyes:

* Two bullet holes of vertical? 'I'm completely out of tune. Go up or down around .6 grains or so and I should be reasonably in tune at either the top or bottom stop of the muzzle swing. But which one? Beats the 'ell outta' me! :rolleyes::p:o

"Damn, I knew I shouda' bought one of those Beggs tuners years ago, then I wouldn't have to be carrying all these different loads to the line. :mad: I could simply make an adjustment to the tuner at the line and never have to change the load, EVER. :rolleyes:

Yep, it's true, believe it or not. Getting the rifle in tune by adjusting the tuner is just like adjusting the focus on an old Leupold 36 target scope. How do you get one of those beautiful old 36's in focus? Why, you loosen the lock ring and rotate the focus ring in one direction or the other till the target image is clear. :) ""But what if you go the wrong way?? Simple, if the image get worse, you went the wrong way; go back the other way till it gets clear.

Now,,, what about focusing a tuner/barrel??? Same way as focusing the scope. With a Beggs tuner which is 28 tpi thread, you cannot possibly be more than a half turn out of tune. Shoot a 3 shot test group on the sighter. The rifle will tell you one of three things;

1. Little or no vertical; I'm in tune. Go to the record.

2. About one bullet hole of vertical; I'm only about a quarter turn out of tune. But which way? Reach up there and give the tuner a quarter turn in either direction. If the next test group increases to two bullet holes of vertical, you went the wrong way. (That's usually what happens to me.) Go back where you were and make a quarter turn in the other direction and you'll be in tune. Go to the record.

3. Two bullet holes of vertical; fully out of tune. A half turn in either direction will put the rifle in tune. But will I be tuned to the top or bottom stop? Who cares? In tune is in tune. :rolleyes:

Hope this helps. For a while, I was beginning to think no one was even listening and didn't care to discuss this further.

Later

Gene Beggs
I'm listening and I agree, Gene. Tuners are so easy to use it's crazy, and they work as you've described, IME. The only thing I'll add is that the needed adjustment is nominal in that different tuners, threads, weight, position relative to muzzle, barrel STIFFNESS, etc., all come into play in determining just how far the tuner needs to be moved for a given effect.

Therefore, rather than matter of factly stating that every gun and tuner will be completely in or out of tune with a 1/2 turn...I simply state that small adjustments matter, to be very much methodical when testing, that big swings are likely to make you miss a tuning node and that once you establish what in and completely out of tune are relative to tuner movement, I've never seen the need to adjust beyond that small window of movement. IOW, If you're gun is completely in tune at the zero mark on the tuner, and completely out at the 4 mark..there is no reason to adjust anywhere beyond that zero to 4 range. I will add to that, that because as you pointed out, the tune will repeat itself. So, if you're completely out of tune it doesn't matter which way you go. you could go back to zero...or you can go to 8, and be back or very near in tune. IME, a tuner will be just as effective if it only had a single revolution(or less) of total range of motion, as with inches of threads on the barrel.
I suppose it's human nature to see all those threads and assume you need to use them.:confused: You do not...at least not with any tuner and barrel that I've ever seen.

There are seemingly endless conversations..or debates about HOW tuners do what they do and they all get confusing. But the important thing is that while they are hard to understand how they do what they do, it couldn't be simpler to use one. Just get your information from the person that made your tuner and forget about how far anyone else says to move your tuner. It's apples and oranges. They all work on the same principle, but that's where it ends.

Gene Beggs
09-28-2015, 06:41 PM
I'm listening and I agree, Gene. Tuners are so easy to use it's crazy, and they work as you've described, IME. The only thing I'll add is that the needed adjustment is nominal in that different tuners, threads, weight, position relative to muzzle, barrel STIFFNESS, etc., all come into play in determining just how far the tuner needs to be moved for a given effect.

Therefore, rather than matter of factly stating that every gun and tuner will be completely in or out of tune with a 1/2 turn...I simply state that small adjustments matter, to be very much methodical when testing, that big swings are likely to make you miss a tuning node and that once you establish what in and completely out of tune are relative to tuner movement, I've never seen the need to adjust beyond that small window of movement. IOW, If you're gun is completely in tune at the zero mark on the tuner, and completely out at the 4 mark..there is no reason to adjust anywhere beyond that zero to 4 range. I will add to that, that because as you pointed out, the tune will repeat itself. So, if you're completely out of tune it doesn't matter which way you go. you could go back to zero...or you can go to 8, and be back or very near in tune. IME, a tuner will be just as effective if it only had a single revolution(or less) of total range of motion, as with inches of threads on the barrel.
I suppose it's human nature to see all those threads and assume you need to use them.:confused: You do not...at least not with any tuner and barrel that I've ever seen.

There are seemingly endless conversations..or debates about HOW tuners do what they do and they all get confusing. But the important thing is that while they are hard to understand how they do what they do, it couldn't be simpler to use one. Just get your information from the person that made your tuner and forget about how far anyone else says to move your tuner. It's apples and oranges. They all work on the same principle, but that's where it ends.


Well said Mike. Thank you.

Gene Beggs