Anxious for clear weather to try Beggs Tuner

Bryce

I may be wrong, but the whole theory behind this is once the muzzle is "stopped", the velocity of the load makes no difference. Remember, you are finding a weight that will make two extreme velocity spreads go into the same hole. The trick is,you have to find the weight, Through trial and error, and be darned sure about it.
Lynn gives a good discription in his post castegating me. The light finally came on when it dawned on me that we are not talking about 20 ounces here. What we are talking about is what ever weight it takes to stop the muzzle on a particular barrel, or complete Rifle.
I am darned sure going to try it.........jackie
 
Vibe, That is what I am getting at, sort of.

Finding an accurate load doesn't seem to mean anything once the tuner is added. Finding a internal ballistically efficient load seems more logical, then go either side of that load to tune the barrel/tuner combo to that load. So long as you can in fact go over that load in safety.
 
Jackie,

I know you feel there is more to load tuning that just finding a load that suits the barrel. I understand, and I agree, that you feel there is something in the hot loads that just work better in terms of the internal ballistics.

What I am saying is why not pick the best load in terms of nice uniform velocity and then go either side of that and set the tuner up. Then go back to the mid way load and logically it'd be in tune as well.

Or you could just pick a load that was convenient for whatever reason, no need for a drop tube say like 29 grains, and go either side of that and then back to the mid way load.

I just struggle with the logic of using a load at the end of the range of loads used to set up the tuner, seems you are at the end or closer to the end of the tune window.

Logically the "tuned" barrel/tuner is not in fact tuned for any old load you please, just for a velocity range. If you tuned it to shoot at say 3300fps with 29 grains of N133 I am assuming it will not now shoot at 2800fps with a mild load of H4198 or in fact with a bullet of a different weight ??????

I get the overal concept (I think) but the details as they have been spelt out thus far seem contrary to my version of logic !! :)

Jackie, since it sounds like you are going to some bother to set this thing up could you spend another 20-30 minutes and try this for me. Load at 27.5 and 30.5, set the tuner with those loads and then shoot a couple of groups at 29 grains. Also one group at say 24 grains, I bet 29 shoots and a real mild load like 24 won't, it will be to far outside the tuned velocity window.

Bryce
 
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I'll have to defer to the guys with real long range experience, but all other things being held equal, the lower ES loads have always sounded like the loads to go with. No sense expecting the muzzle device/tuner to do all the work. :D Just pick up the slack.

I'm thinking it is an assumption on your part that the pre-tuner "good load" is on one extreme side of the sweet spot.
 
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Jackie, I applaud you :):):) keep up the good work. With you and Jim in it we'll get to see that much more solid data. I know you've been itching to try this thing but couldn't get anyone to give you a place to start :)

THANK YOU BOTH for sharing your findings here!


al
 
Vibe said:
the lower ES loads have always sounded like the loads to go with.
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The problem is, you can't get velocity variations that low. Use a ballistics program, and look at the difference in drop for 1,000 yards with a 10 or 15 fps variation. BTW, holding it to 10 fps is very hard to do. Winning groups smaller than that, which is why you need load tuning, in some fashion.
 
Charles E said:
The problem is, you can't get velocity variations that low. Use a ballistics program, and look at the difference in drop for 1,000 yards with a 10 or 15 fps variation. BTW, holding it to 10 fps is very hard to do. Winning groups smaller than that, which is why you need load tuning, in some fashion.
Click to expand...
I'm sorry Charles, where did I mention how low it was that I thought the variations needed to be?
 
I think what Charles was getting at was even 10-15fps, which is very good, will not get the vertical as small as needed if the load wasn't tuned to the barrel to gain some degree of compensation for the slower rounds.

I wonder if the same is true at 200 with a PPC. Is it actually possible to shoot a 0.10 say at 200 with loads that might vary by say 50fps. The barrel/load/tuner set up is actually compensating for the variation and shooting better than is theoretically possible if the load left a dead still barrel.
 
Bryce

I have shot 10 shot 100 yard groups with my Rail Gun, over my 35p Chrono, that showed 35 fps variation, that measured smaller than .150........jackie
 
Yes Jackie, but I'd bet your load was tuned to take out the vertical.

All I'm trying to say is that tuning, either by the load or some other devise, is needed. You can't get the vertical out simply by trying to get ES/SD low enough.

All it takes is a ballistics program. Change the velocity for two *shots.* Set the "zeroed" distance to muzzle, and finally, read off the bullet drop for the two shots. That will tell you the vertical that is in the velocity variations. It is worse as the range increases.

Also, remember that in the real world, there is a bullet exit time where the barrel is working against you as well -- you can tun in vertical as well as tuning it out.

Again, no big deal, just the little point that the excellence of you loads isn't going to eliminate the need for tuning.
 
I've been reading this with...

a good deal of interest. About two or three years ago when the subject of tuners came up there was a lot of negativity... a whole lot. There seem to be many more open minds now.:)

I made up two "tuner barrels" for my LV gun in 2005. One was a disaster... the barrel maker should never have shipped the barrel. I tried the other one with a tuner that was sloppily made and which rattled. This spring I will put the better barrel back on the gun with a tuner that can be locked up and try again.

These barrels had a 1.150" chamber slug which extended 2" beyond the action. Then they stepped down to .840" the rest of the way to the muzzle. My old notes show some promise for the better barrel. We'll try it again.

It's going to be fun this year shooting in matches were my tuner isn't illegal.;)

Dick Wright
 
This may or may not be relevent

Several years ago a fellow who calls himself Dr. D sent me a seminar on using seating depth to find one's tune. I have been using it since. I shoot to find the best crono numbers at the fastest speed I can get to. I then use seating depth to find a round hole. I don't see why simply tuning to the speed one wants to go will not work. If we can assume that , if we could get there, a much faster load would go in the same hole as the one we like. I think once we find Nirvana for a particular barrel , we are home.
 
OK, while we wait ........

Could one of you ballistician types please run some midrange trajectory numbers?


If bullet #1 is traveling at 2900 fps and is launched at an angle such that it's "zero'd" at 1000yds........

And bullet #2 is launched at 2950 fps or 50 fps FASTER and is also angled to "zero" at 1000yds.......


What is the figured spread at the "max ord" or whatever you want to call the "midrange trajectory"? What is the figured spread at 600?


My memory tells me that there will be approximately 10" difference in drop @1000 and my feeble mind SWAG's that the difference in the middle would be around a inch and a half............what I'm trying to point out is that it's better to tune for the longer range BUT that if you're shooting 600yds you'd best retune for it.


And that even a "stopped" muzzle (broad tuning window?) can only be good for one yardage.....Bryce, does this go along with your questions? My contention is that no matter HOW we tune, that if it's working as described then it need be yardage-specific.


It is really exciting to see so much agreement though regarding what tuning actually entails, I remember that for me it was a real eye-opener to hear Jim Borden describe in words and with pictures the "sine wave" method of tuning...........back in '99. Maybe Jim will tell us how long he's been exploring this concept...?.... (you may regret posting here Jim :D:D now that we've got you talking you may be held hostage for a while :) )


I also remember that ever since tuning has been used, the rule of thumb has been "tuning at 200 can be OK for both yardages, but tuning at 100 and shooting 200 can be a train wreck".


That said, quite a few people DO tune at 100 for both yardages, this doesn't make it "right." ;)



al
 
The good old days...??

Occasionally I go back and read Dan Hackett (dec) and Henry Childs (HBC) discussions about the POI vs ES/SD we get from our top quality chronographs.

Especially in Henry's discussions, I am reminded that we sometimes have greater instrument error than what the ES/SD numbers are in raw variants.

They point out that trying to relate 100 yards results to ES/SD and setting the screens at anything less than about 16 feet we are wasting our time if we expect the chrono to tell us anything but a Guesstimate of how fast the bullet is going.

For example- http://www.benchrest.com/forums/showthread.php?t=2639&highlight=chronograph

Want some interesting rereading go to the Search function and search for HBC as the "Search by user name" box.
 
Al,

That is exactly what I am saying ........ glad I made enough sense that somebody responded directly to my query !!

If the muzzle is stopped dead so that the last 1/4 inch is always dead parallel to the action all we will achieve is to make the groups the reult of the variation in drop caused by the variation in velocity.

To effectively tune the barrel using the two load approach it seems to me that we want to actually put the dead spot slightly into the beyond the muzzle tuner so that the muzzle itself is pointing lower for a fast bullet than it is for a slow bullet. The muzzle isn't still but moves just enough to counter the velocity and trajectory variations.

That can only mean that the rifle and load is only in perfect tune for one range and will also only be in tune over a certain velocity range such that the change in muzzle angle at bullet departure compensates for the velocity change. A bullet doing 2750fps will need more help to match the point of impact of one doing 2850fps than a bullet doing 3300fps will need to match the point of impact of one doing 3400fps.

I just googled up an old Calfee article with some nice pictures that help make sense of what he is saying now. I do believe the tuner needs to be forward of the muzzle to attain the stopped or not quite stopped muzzle. Having the tuner beyond the muzzle will allow the vibration to carry on past the muzzle and thus allow the short parrallel section of barrel to be placed anywhere we please relative to the muzzle.

I have no experience with tuners but have been following all this stuff. Seems to me that logically the only way to achieve the broad tune window is to have a beyond the muzzle tuner and set it so that bullets a little slower and a little faster then the desired load will land in the same group at the desired distance, then go back to the desired load in the middle of the two loads used to set the tuner. When moving to a different shooting distance a different tuner setting would be needed to compensate for the change in drop not matching the angular change the muzzle positiion created at a shorter range setting. That is if going from 100 to 600 the tuner will need to launch the slower bullet a bit higher to have the same point of impact as the slower bullet than it did when matching different velocities to the same point of impact at 100. The muzzle variation at bullet release is angular but the bullet drop is not. The muzzle position change gets 6 times as far apart at 600 as it does at 100 but the velocity change creates more than 6 times the change in bullet drop.

http://www.ozfclass.com/articles/1/psm_2005_03.html


Bryce
 
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Good point Jerry,


I think that this illustrates exactly why tuning is so important, not only are few of us equipped to accurately measure velocity, getting the ES down in some barrels can be maddening.


And then you get the one that you could just blow the bullets through and they'd go the same speed....... :confused:



Bryce,


Does it? :)

Think "outrigger" ......... think of the balancing pole of a ropewalker....... is "forward" any different than "outward"? After all, "forward" is simply replacing a section of barrel with an adjustable piece, it doesn't in any way change what's going on........


IMO :D



al
 
Have a look at the Calfee article I linked to.

If Bill is right and a barrel will always have a small section of barrel near the muzzle that will vibrate in the opposite direction to the rest of the barrel such that the area say an inch behind the muzzle is "parallel" then the "barrel" needs to extend beyond the muzzle to be able to place the "parallel" on the muzzle. That means weight needs to go beyond the muzzle or the muzzle need to be counterbored like Jim Borden has done in that rifle mentioned earlier.

Pop a little weight on the end of a length of stiff wire and wiggle the wire. No matter what weight you add to the very tip of the wire the tip will always move, the "parallel node" or stopped piece will always be a little bit behind the weighted tip.

I don't know for certain about this stuff obviously but I am becoming more convinced that Bill is totally 100 correct in what he is saying.

I believe:

To get the best effect the tuner must go beyond the muuzle.

Tune with loads having velocities just either side of the load you actually plan on using.

The set up will still only be in perfect tune at one distance due to the nature of the change in trajectory of different velocity bullets over different distances.

A tuner that is located rear of the muzzle will only ever be an alternative to tuning with the load only, you can control the exit angle to a point but not so precisely since you can never have the parallel area at the actual muzzle or close enough to the muzzle to achieve the two velocity in one group deal over a small velocity spread.

Now all I need is to get a tuner and try this stuff for myself !! :)

Bryce
 
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Everybody I Had To Go To Work

Jackie
I would use your existing barrel and your existing tuner body and just turn some weights.After you get a handle on things yo can do a second barrel if you feel it is necessary.
I wsn't picking on you I was merely getting your attention.

Alinwa
You better get your lathe cranked up and start making chips beause March 15th is 12 days away.

Bryce
In your post #76 the 3rd paragraph is correct.The muzzle acts just like the pivot point of a teeter totter.On both sides of the pivot point everything is moving like crazy but that pin is essentialy motionless.
Bill Calfee is definitely right on this and we should all thank him for enduring the treatment he put up with before beating this into our brains.

Shelley
Any tuner out there that extends past the muzzle can be fitted with varying weights in order to find the correct one.Once that is done you simply make a wight that size.

Everybody as Charles E has said you still need to tune the rifle and its still all about who has the best bullets.

Bill Calfee I think it was very generous of you to put up with all the bad talking that went on.I think we are pointed in the right direction.
Your Friend
Lynn
 
Lynn,


Read the article Bryce posted if you haven't already.


I'm showing up the 15th with one completely worn out 6BR on a Borden chassis and one nearly new 6BR Shilen on a worn out 700 chassis................and NO TUNERS :D:D I can't stand 'em! They drive me batty.


This match caught me out badly, I have nothing competitive set up and nothing tuned but hey, I'd show up with a slingshot! It's in my back yard and I'm not working much A'tall this winter.


I DO have some totally deadly Euber 108's though, from the first die ........ And I will be shooting right here in the same weather from tomorrow on .............. trying for a tune.



BTW I finally got the lathe all assembled and ready, she's settling in as we speak.



al
 
Alinwa

That first batch of Eubers was a dandy.I gave some to the bullet god Henry Childs and he liked them alot.The only problem I had with them was they are 0.076 longer than most of the other bullets in there weight range.Meaning a freebore longer than 0.110 is needed.
Longshot1(Bert Seltzer) has won any awards using them at the various national events.

It sounds like your gun has lots of experience.We swap out the barrels every year now but I doubt any of them are truly worn out.

If we make the shoot we'll bring 3 6BR's and a 6mm-06 for lightgun and a pair of 300 Ackley's for heavygun.I have yet to go to the weather underground website to see what kind of weather we'll be dealing with so I'll bring my trusty 6mm-06 just in case it blows.

No tuner yet!!!!!!! Haven't you been reading all of the posts on this forum?

I did read that article and I visit the Bill Calfee website from time to time just to see what is going on.

See you in 12 days.
Lynn
 
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