Boyd Allen
Active member
I know good shooters that use anything from .0005 to between .002 and .003. What clearance do you use (loaded round to chamber neck) and why? Have you tried anything else?
What have you tried for neck clearance, and how did it work?
- Thread starter Boyd Allen
- Start date
Kent Harshman
Member
Neck Clearance
Boyd,
After running neck clearance pretty close...probably about .0005" for a long time...I've opened it up to the point that I can "slip fit" a bullet back into a fired case in the last 6-8 years. Why?... Well, I used to get the occasional "flyer" with the tight neck clearance, and while I have no good reason to suspect that it was my neck clearance, I just opened it up to have one less question about the "flyers". Currently, my loaded rounds measure ~ .2615", and my chamber is .263". When fired, I can easily "slip fit" a bullet back into a fired case. That's what I've been using for the last 6-8 years with some modest success in competition...
Boyd,
After running neck clearance pretty close...probably about .0005" for a long time...I've opened it up to the point that I can "slip fit" a bullet back into a fired case in the last 6-8 years. Why?... Well, I used to get the occasional "flyer" with the tight neck clearance, and while I have no good reason to suspect that it was my neck clearance, I just opened it up to have one less question about the "flyers". Currently, my loaded rounds measure ~ .2615", and my chamber is .263". When fired, I can easily "slip fit" a bullet back into a fired case. That's what I've been using for the last 6-8 years with some modest success in competition...
Boyd Allen
Active member
Thanks Kent, that was just the sort of tip that I was looking for.
JerrySharrett
Senile Member
I've used Joe K's "loose to win" (0.003"), the standard 0.002", fitted neck (0.0005") and step neck where the part the bullet fits in is a tight slip fit and the part below that is tighter. They all work if properly applied. IMO, there is no "magic" neck trick but the Joe K neck is probably the most forgiving.
I've even gone to 0.005" and can still get a good tune. The 0.005" case will not last as long though.
I've even gone to 0.005" and can still get a good tune. The 0.005" case will not last as long though.
jackie schmidt
New member
Boyd
I too have settled in on .0015 loded round neck clearance, any tighter and I think you are at the risk of getting a flyer.
I can just slip a Bruno Boat Tail into a fired case, which seems to be about right.........jackie
I too have settled in on .0015 loded round neck clearance, any tighter and I think you are at the risk of getting a flyer.
I can just slip a Bruno Boat Tail into a fired case, which seems to be about right.........jackie
R
RayfromTX
Guest
Why would it cause a flier? This is interesting. Anybody know the answer or is it from experience and anecdotal evidence?
jackie schmidt
New member
Ray
If everything is dead to the nuts perfect, it probably will not.
I think the idea is if you get a case neck, that for what ever reason, does not let the bullet release as it should, you could get a pressure spike, hense a flyer.
Of course, this all could be speculation. But since there does not seem to be any advantage to having necks any tighter, then why risk it.
Back "in the days when", there was the concept of "fitted necks". This entailed giving the loaded rounds the very minimum clearance that it took to release the bullet, you did not even have to resize the necks for the next firing.
I do not know anybody that does that now.
A good test for Gene Beggs in his Tunnel would be to take 20 cases, five with .0005 clearance, five with .oo1, five with .0015, and 5 with .002, and shoot enough groups with each set of cases to see at what point they were too tight, or too loose.
The way we shoot these 00 radius bullets, with that gosh awfull jam, I doubt the necks are even touching anything anyway.........jackie,
If everything is dead to the nuts perfect, it probably will not.
I think the idea is if you get a case neck, that for what ever reason, does not let the bullet release as it should, you could get a pressure spike, hense a flyer.
Of course, this all could be speculation. But since there does not seem to be any advantage to having necks any tighter, then why risk it.
Back "in the days when", there was the concept of "fitted necks". This entailed giving the loaded rounds the very minimum clearance that it took to release the bullet, you did not even have to resize the necks for the next firing.
I do not know anybody that does that now.
A good test for Gene Beggs in his Tunnel would be to take 20 cases, five with .0005 clearance, five with .oo1, five with .0015, and 5 with .002, and shoot enough groups with each set of cases to see at what point they were too tight, or too loose.
The way we shoot these 00 radius bullets, with that gosh awfull jam, I doubt the necks are even touching anything anyway.........jackie,
-Ray, too tight and there is a good chance combustion residue(you know the stuff you clean off of your case necks )can get between the neck and chamber walls and create a hiccup(for lack of more precise terminology) aka "flier".
I have a question for Kent ,Jerry and Jackie. You guys are talking about slip fitting a bullet in a fired case, does that mean you shoot that way without sizing the neck down ,or are you using the bullet slip fit as a "feely guy"( as Shelly used to say) gage to determine neck clearance; and then bushing down during resize to establish a desired neck tension ?
Joel
I have a question for Kent ,Jerry and Jackie. You guys are talking about slip fitting a bullet in a fired case, does that mean you shoot that way without sizing the neck down ,or are you using the bullet slip fit as a "feely guy"( as Shelly used to say) gage to determine neck clearance; and then bushing down during resize to establish a desired neck tension ?
Joel
R
RayfromTX
Guest
Thanks Jackie,
That makes sense now.
That makes sense now.
jackie schmidt
New member
Ray
Tomorrow, a bunch of us will be up at Tomball. I have about 200 cases that I sorted through, that all still looked good and sized down real nice. Most had at least a 2-Gun events worth of shooting on them..
I set up my lathe, and returned every one, probably taking off each one just enogh to make the necks all identicle again..
They will now have close to .002 loaded round neck clearance. I will shoot some tomorrow and see how they do.........jackie
Tomorrow, a bunch of us will be up at Tomball. I have about 200 cases that I sorted through, that all still looked good and sized down real nice. Most had at least a 2-Gun events worth of shooting on them..
I set up my lathe, and returned every one, probably taking off each one just enogh to make the necks all identicle again..
They will now have close to .002 loaded round neck clearance. I will shoot some tomorrow and see how they do.........jackie
Boyd Allen
Active member
Jackie,
You probably know that .002 is not the upper limit for good results, but just in case you didn't, a current NBRSA record holder once told me that his neck clearance is somewhere between .002 and .003...something about a cleaner bullet release.
Sometimes I think that it is a good idea to set a caliper at .001 and look at it, just to remind myself just how small it is. Throwing numbers around, it is easy for me to loose perspective on just how little a difference is being discussed.
You probably know that .002 is not the upper limit for good results, but just in case you didn't, a current NBRSA record holder once told me that his neck clearance is somewhere between .002 and .003...something about a cleaner bullet release.
Sometimes I think that it is a good idea to set a caliper at .001 and look at it, just to remind myself just how small it is. Throwing numbers around, it is easy for me to loose perspective on just how little a difference is being discussed.
JerrySharrett
Senile Member
Joel, I hope Wilbur will chime in here. I've seen him and Tommy McKee shoot by just re priming, dumping powder and let the bullet sit on top of the powder column. I've tried that in practice but never in a match.
As to the so called "fitted neck", the fired case neck will be small enough that resizing the neck is not necessary to hold the bullet where the seater puts it. The example above and Wilbur and Tommy's situation the bullet just slips in and sets on the powder, on the fitted neck the bullet requires some press. The disadvantage of this method is there is no control of neck tension.
In the step neck, the neck is turned twice. The first turn is as normal for a fitted neck (no resizing required). Then the case necks are re-turned by about 0,002" down to the point to where the bullet base sets. Then the bullet just sets on the shoulder, now inside the case, where the 0.002" clearance is. This one doesn't make a lot of sense but Ferris Pindell and a few others swore by it....for a while. The disadvantage of this method is there is no way to adjust bullet jam. It is always a jump situation.
Kent Harshman
Member
Neck Tension
Joel,
NO!...we're not then shooting them that way...at least I know that Jackie & I aren't. I'll let Jackie respond for himself, but based on how much 'jam' he talks about using, I know that he uses significant neck tension...
As for me, in the previous example I gave, where a loaded round measures ~ .2615", I'll use a .260 bushing MOST of the time, and occasionally a .259 bushing if I find that it seems to tune better. I don't use as much neck tension as most guys do with 133...just never found that it worked that much better for me. The "slip-fit" deal is as Jackie describes...just so you don't have the possibility with any round of a 'less-than-perfect-release' of the bullet from the case.
Joel,
NO!...we're not then shooting them that way...at least I know that Jackie & I aren't. I'll let Jackie respond for himself, but based on how much 'jam' he talks about using, I know that he uses significant neck tension...
As for me, in the previous example I gave, where a loaded round measures ~ .2615", I'll use a .260 bushing MOST of the time, and occasionally a .259 bushing if I find that it seems to tune better. I don't use as much neck tension as most guys do with 133...just never found that it worked that much better for me. The "slip-fit" deal is as Jackie describes...just so you don't have the possibility with any round of a 'less-than-perfect-release' of the bullet from the case.
A
abintx
Guest
Here's additional comments from others at ...
Benchrest Central Tips, Tricks, & Info
How much neck clearance do you try to achieve and what kind of neck tension do you like ? - Multiple
Tom Rollins
I turn to get .0005 all the way around or .001 in all of a loaded round. I know that's pretty tight but sure makes the brass last a hell of a long time and both rifles seem to like it. I don't have to size the necks down a lot to get a good hold on the bullet that way either. One of my rifles likes not so tight neck tension (around .001 tension) while the other likes it semi-tight (.002 tension). Neither rifles likes the tension to be much more than a .002 tension for some reason. I don't know why but Clay Spencer said his rifles are the same way, some like it semi-tight to tight while some like it a lot less. I have a friend up here that turns for .00025 per side on clearance on his loaded rounds. He never has to neck size his brass as it automatically springs back enough to hold a bullet after each shot. All he does is clean the outside and inside of his necks, reprimes, adds his powder and tops it off with a bullet seated out too far thus letting the lands seat the bullet back for him when he closes the bolt. I would never do it that way but get this, he always seems to group in the .1xx's. His method also takes half the time to do his reloading as people using the usual BR method of reloading.
Walt Berger
My reamer has a .262 neck. I turn brass to 8.8 and use a .259 sizing button.This works very well for us with moly bullets. Our bullet has a .2434 pressure ring and measures .2431 just ahead of the pressure ring.
Bart Sauter
With a .262 Chamber and I trim my Brass to 8.8. So with a 243.5 bullet that gives me a little less then a thousands clearance. I use heavy neck tension 257. Carbide Bushing.
Ray Wight
With a .262" chamber, my cases are cut to .0086" which gives me .0014" (.0007" per side) clearance with a .2434 bullet (if everything goes as planned.) Then I use a .259" button in the neck sizer which gives me fairly good tension (.0016" squeeze.) Usually, I have the bullet stuck into the lands firmly leaving a rectangular mark (1/2 high as wide.) That is my formula, which is derived from Ron Hoehn, World Champion. It will be interesting to see what kind of consensus there is on this subject, if any.
Ron Galbraith
I use Lapua .220 Russian brass ( doesn't everybody ) to fireform into 6PPC cases. After necking up the Lapua and after the appropriate sizing, etc. I turn the brass in three steps so that I get a loaded neck diameter of .2605 inches ( for a .262 chamber neck ). This leaves a total clearance of .0015 between the neck and the chamber. The thickness of the neck walls at this point is about .0085 but this varies with variations in the particular bullet ( or lot ) that I'm using. I have not found any problems with small variations in bullet diameter as long as the loaded round does not measure over .261. I don't want to go over .261 as I don't feel there is any real advantage accuracy wise. The disadvantages though would be too much of a bother. This includes increased time making sure the necks are not thickening further, watching for burrs, etc. Not worth it. As far as neck tension goes, I like to use a "medium" tension. I can get this with a .259 bushing. As long as the bullets seat smoothly and with an even feel I have had good luck. I don't feel comfortable with a tension that is too loose as I am not confidant that the seating depth would remain constant with handling, etc. I am planning on a stint with moly coated bullets so I think that I will have to increase neck tension somewhat to counteract the affect the moly will have on gripping the bullets. This will be a trial and error procedure until I get the "feel" that I am used to. For the most part though, I think neck tension is a function of the barrel you are using. Some barrels seem to like more tension than others. I also believe neck tensions take on more significance if you like to jump the bullets, as opposed to seating them into the lands. You could spend a lot of time trying to find that sweet spot, but I believe other variables, such as seating depth, bullet diameters, etc. are more worth pursuing.
Mike Bryant
My 6 PPC use a .262 neck diameter on the reamer and .246 for my .22 Waldogs. I use .002" clearance for a loaded round diameters of .260" and .244" respectively. I use a .258 bushing in my neck die and then go to a .257 bushing when the .258 won't hold the bullet. With the .22, I use a .242 and a .241 bushing.
Allen Arnette
I like .001 clearance on each side.I change my neck tension a lot from barrel to barrel.I sometimes change tension to change pressure without changing powder charge or seating depth.
Jerry Peckumn
I am relatively new to tight neck chambers and use loaded 6 PPC rounds measuring .261 for a .263 neck.
Mickey Coleman
If there's anything I hate is for my collars to be too tight. I don't guess you're asking about my shirts, are you?
I have three guns and each one has a different neck diameter due to when they were built but, generally speaking, I try to have at least .001-.002 total clearance (just to be safe and I don't think an extra thousandths clearance will make any difference) on the gun I happen to be shooting. Another variable I encounter is that my Pindell dies make a 'fat' bullet that mikes .2446 on the pressure ring so I have to allow for that when I'm shooting those bullets. I'll eventually retire those dies except for emergencies due to that very fact.
I like a firm grip on the bullet with the case neck (shooting the 'fat' bullets means I have to have a special set of cases just for those bullets in order to keep the same neck tension). I'll generally use a .257 bushing in my bump die and by changing the neck thickness I can keep the same tension regardless of the bullet I'm shooting.
Now that I've written all this down I see what a pain it is shooting the 'fat' bullets and I'll probably quit for sure now that Roger Avery fixed my other die (and he did a SUPER job on it).
Roger Haney
I SHOOT,NAW,I GET .002 EXPANSION AND I LIKE NECK TO BE ONLY TIGHT ENOUGH ,SO I CAN SEAT BULLET WITH MY THUMB WITH LITTLE EFFORT.IN REALITY THAT = ABOUT 2 INCH/LBS. IT REALY DEPENDS ON THE BRASS YOU ARE USING,IF NORMA ,YOU NEED LESS CLEARANCE IN NECK AREA,BUT IF USING LAPUA WHICH IS HARDER,YOU NEED LESS CLEARANCE TO GET PROPER SEAL,THE STUFF DON'T EXPAND GOOD. I USE A .262 NECK,AND I LIKE TO HAVE LOADED ROUND TO MEASURE .2605 TO 2615 WITH LAPUA BRASS.
Bill Giel
6 PPC .262 neck, loaded round 0.261+, no more than 0.2615, all must be exactly the same.
J. D. Denoff
We use a .001 or .0015 neck clearance. Neck tension depends on which powder we use. H322 seems to work best with a medium too light tension. We Just recently switched to Vit. 133, Took us awhile to find the right combination but a heavy neck tension seems to be the best for V133.
Wilbur Harris
I like to have .001 clearance for the loaded round (.0005 each side. Any deviation from this should be in the more clearance direction as the last thing I want is to have trouble at a match with not enough clearance. The necks should be consistent from case to case and if I experience differences I immediately reduce neck tension as much as possible and still maintain a hold on the bullet such that it cannot be casually moved with the fingers. If my cases feel consistent, I like firm neck tension. Consistent necks are pure luxury for me as I seldom achieve this feat.
John Whitley
I shoot for .0015 clearance . Neck tension depends on the gun and or powder. Normally I shoot .001-.002 neck tension whichever the barrel or brass likes. But I have found that N133 seems to like more tension (.003 grip).I get vertical with not enough tension with N133. Also coated bullets seem to work better for me with allot of tension and well into the lands.
Billy Stevens
I use Lapua brass and cut it to .0088 for a 6PPC with .262 neck which gives me just under .001 clearance on bullets with a .2435 pressure ring. I don't run into any problems if I keep the necks clean and occassionally check to ensure that I maintain at least .0005 as the necks grow from the brass flowing forward from firing. I only use a set of brass for about three matches and them trade them in for some new ones. I shoot V133 powder with the PPC and like to use a .257 button which will give a fairly heavy neck tension with the above setup. For me, V133 will not shoot as well unless you have heavy neck tension.
Rich Griffin
There are many variables to the neck clearance in the chamber. First, I like about 1 to 1.5 thousands of neck clearance, which allows me to turn the necks to 8 thousands with a .260 neck. I feel if you go too thin it works the neck too much. We have been chambering with a 6BR reamer that Bill Downey has which we have shortened to .100. So for this is working well. As for the neck tension, I like my neck tension to be tight and I use a .257 bushing.
Glenn Newick
That's a good question. I feel that proper and consistent neck tension is one of the important factors in shooting great aggregates. An additional question would be how much bullet engagement do you like in the lands. The two absolute killers are: Too much neck tension and too much land engagement (jam). The best rifle in the world will shoot 1/2" without enough clearance to release the bullet. I shoot a minimum of 1 thou. That's an actual 1 thou, not 1 thou less than the listed neck dimension on the reamer. Many reamers seem to cut slightly larger than listed. I think some of that might be related to the individual gunsmith's technique. Another question for you. When shooting the 1 thou, I don't size before seating a new bullet, just punch out the primer and reload. With more than that, I never go past two thou. If using that clearance I size with a neck-sizer. For preferred neck tension, I find that the minimum neck-tension that will securely hold the bullet seems to give the best groups.
Dave Kiff at Pacific Tool and Gauge told me he recommends .0025-.003. Art
Benchrest Central Tips, Tricks, & Info
How much neck clearance do you try to achieve and what kind of neck tension do you like ? - Multiple
Tom Rollins
I turn to get .0005 all the way around or .001 in all of a loaded round. I know that's pretty tight but sure makes the brass last a hell of a long time and both rifles seem to like it. I don't have to size the necks down a lot to get a good hold on the bullet that way either. One of my rifles likes not so tight neck tension (around .001 tension) while the other likes it semi-tight (.002 tension). Neither rifles likes the tension to be much more than a .002 tension for some reason. I don't know why but Clay Spencer said his rifles are the same way, some like it semi-tight to tight while some like it a lot less. I have a friend up here that turns for .00025 per side on clearance on his loaded rounds. He never has to neck size his brass as it automatically springs back enough to hold a bullet after each shot. All he does is clean the outside and inside of his necks, reprimes, adds his powder and tops it off with a bullet seated out too far thus letting the lands seat the bullet back for him when he closes the bolt. I would never do it that way but get this, he always seems to group in the .1xx's. His method also takes half the time to do his reloading as people using the usual BR method of reloading.
Walt Berger
My reamer has a .262 neck. I turn brass to 8.8 and use a .259 sizing button.This works very well for us with moly bullets. Our bullet has a .2434 pressure ring and measures .2431 just ahead of the pressure ring.
Bart Sauter
With a .262 Chamber and I trim my Brass to 8.8. So with a 243.5 bullet that gives me a little less then a thousands clearance. I use heavy neck tension 257. Carbide Bushing.
Ray Wight
With a .262" chamber, my cases are cut to .0086" which gives me .0014" (.0007" per side) clearance with a .2434 bullet (if everything goes as planned.) Then I use a .259" button in the neck sizer which gives me fairly good tension (.0016" squeeze.) Usually, I have the bullet stuck into the lands firmly leaving a rectangular mark (1/2 high as wide.) That is my formula, which is derived from Ron Hoehn, World Champion. It will be interesting to see what kind of consensus there is on this subject, if any.
Ron Galbraith
I use Lapua .220 Russian brass ( doesn't everybody ) to fireform into 6PPC cases. After necking up the Lapua and after the appropriate sizing, etc. I turn the brass in three steps so that I get a loaded neck diameter of .2605 inches ( for a .262 chamber neck ). This leaves a total clearance of .0015 between the neck and the chamber. The thickness of the neck walls at this point is about .0085 but this varies with variations in the particular bullet ( or lot ) that I'm using. I have not found any problems with small variations in bullet diameter as long as the loaded round does not measure over .261. I don't want to go over .261 as I don't feel there is any real advantage accuracy wise. The disadvantages though would be too much of a bother. This includes increased time making sure the necks are not thickening further, watching for burrs, etc. Not worth it. As far as neck tension goes, I like to use a "medium" tension. I can get this with a .259 bushing. As long as the bullets seat smoothly and with an even feel I have had good luck. I don't feel comfortable with a tension that is too loose as I am not confidant that the seating depth would remain constant with handling, etc. I am planning on a stint with moly coated bullets so I think that I will have to increase neck tension somewhat to counteract the affect the moly will have on gripping the bullets. This will be a trial and error procedure until I get the "feel" that I am used to. For the most part though, I think neck tension is a function of the barrel you are using. Some barrels seem to like more tension than others. I also believe neck tensions take on more significance if you like to jump the bullets, as opposed to seating them into the lands. You could spend a lot of time trying to find that sweet spot, but I believe other variables, such as seating depth, bullet diameters, etc. are more worth pursuing.
Mike Bryant
My 6 PPC use a .262 neck diameter on the reamer and .246 for my .22 Waldogs. I use .002" clearance for a loaded round diameters of .260" and .244" respectively. I use a .258 bushing in my neck die and then go to a .257 bushing when the .258 won't hold the bullet. With the .22, I use a .242 and a .241 bushing.
Allen Arnette
I like .001 clearance on each side.I change my neck tension a lot from barrel to barrel.I sometimes change tension to change pressure without changing powder charge or seating depth.
Jerry Peckumn
I am relatively new to tight neck chambers and use loaded 6 PPC rounds measuring .261 for a .263 neck.
Mickey Coleman
If there's anything I hate is for my collars to be too tight. I don't guess you're asking about my shirts, are you?
I have three guns and each one has a different neck diameter due to when they were built but, generally speaking, I try to have at least .001-.002 total clearance (just to be safe and I don't think an extra thousandths clearance will make any difference) on the gun I happen to be shooting. Another variable I encounter is that my Pindell dies make a 'fat' bullet that mikes .2446 on the pressure ring so I have to allow for that when I'm shooting those bullets. I'll eventually retire those dies except for emergencies due to that very fact.
I like a firm grip on the bullet with the case neck (shooting the 'fat' bullets means I have to have a special set of cases just for those bullets in order to keep the same neck tension). I'll generally use a .257 bushing in my bump die and by changing the neck thickness I can keep the same tension regardless of the bullet I'm shooting.
Now that I've written all this down I see what a pain it is shooting the 'fat' bullets and I'll probably quit for sure now that Roger Avery fixed my other die (and he did a SUPER job on it).
Roger Haney
I SHOOT,NAW,I GET .002 EXPANSION AND I LIKE NECK TO BE ONLY TIGHT ENOUGH ,SO I CAN SEAT BULLET WITH MY THUMB WITH LITTLE EFFORT.IN REALITY THAT = ABOUT 2 INCH/LBS. IT REALY DEPENDS ON THE BRASS YOU ARE USING,IF NORMA ,YOU NEED LESS CLEARANCE IN NECK AREA,BUT IF USING LAPUA WHICH IS HARDER,YOU NEED LESS CLEARANCE TO GET PROPER SEAL,THE STUFF DON'T EXPAND GOOD. I USE A .262 NECK,AND I LIKE TO HAVE LOADED ROUND TO MEASURE .2605 TO 2615 WITH LAPUA BRASS.
Bill Giel
6 PPC .262 neck, loaded round 0.261+, no more than 0.2615, all must be exactly the same.
J. D. Denoff
We use a .001 or .0015 neck clearance. Neck tension depends on which powder we use. H322 seems to work best with a medium too light tension. We Just recently switched to Vit. 133, Took us awhile to find the right combination but a heavy neck tension seems to be the best for V133.
Wilbur Harris
I like to have .001 clearance for the loaded round (.0005 each side. Any deviation from this should be in the more clearance direction as the last thing I want is to have trouble at a match with not enough clearance. The necks should be consistent from case to case and if I experience differences I immediately reduce neck tension as much as possible and still maintain a hold on the bullet such that it cannot be casually moved with the fingers. If my cases feel consistent, I like firm neck tension. Consistent necks are pure luxury for me as I seldom achieve this feat.
John Whitley
I shoot for .0015 clearance . Neck tension depends on the gun and or powder. Normally I shoot .001-.002 neck tension whichever the barrel or brass likes. But I have found that N133 seems to like more tension (.003 grip).I get vertical with not enough tension with N133. Also coated bullets seem to work better for me with allot of tension and well into the lands.
Billy Stevens
I use Lapua brass and cut it to .0088 for a 6PPC with .262 neck which gives me just under .001 clearance on bullets with a .2435 pressure ring. I don't run into any problems if I keep the necks clean and occassionally check to ensure that I maintain at least .0005 as the necks grow from the brass flowing forward from firing. I only use a set of brass for about three matches and them trade them in for some new ones. I shoot V133 powder with the PPC and like to use a .257 button which will give a fairly heavy neck tension with the above setup. For me, V133 will not shoot as well unless you have heavy neck tension.
Rich Griffin
There are many variables to the neck clearance in the chamber. First, I like about 1 to 1.5 thousands of neck clearance, which allows me to turn the necks to 8 thousands with a .260 neck. I feel if you go too thin it works the neck too much. We have been chambering with a 6BR reamer that Bill Downey has which we have shortened to .100. So for this is working well. As for the neck tension, I like my neck tension to be tight and I use a .257 bushing.
Glenn Newick
That's a good question. I feel that proper and consistent neck tension is one of the important factors in shooting great aggregates. An additional question would be how much bullet engagement do you like in the lands. The two absolute killers are: Too much neck tension and too much land engagement (jam). The best rifle in the world will shoot 1/2" without enough clearance to release the bullet. I shoot a minimum of 1 thou. That's an actual 1 thou, not 1 thou less than the listed neck dimension on the reamer. Many reamers seem to cut slightly larger than listed. I think some of that might be related to the individual gunsmith's technique. Another question for you. When shooting the 1 thou, I don't size before seating a new bullet, just punch out the primer and reload. With more than that, I never go past two thou. If using that clearance I size with a neck-sizer. For preferred neck tension, I find that the minimum neck-tension that will securely hold the bullet seems to give the best groups.
Dave Kiff at Pacific Tool and Gauge told me he recommends .0025-.003. Art
Bob Kingsbury
New member
I have used fitted necks and clearanced necks, both shoot well.
As cases are used, they become nicked almost imperceptably.Fitted necks
go down hill fast then. Chamfering without polishing off the secondary
burr that is created is even enough to do this. I doubt that ejectors
and fitted necks get along for any length of time. A barrel I have
with .264 neck and used .2635 loaded rounds , now uses a .2605
loaded round and has not declined at all. The little nicks, that
you can barely feel, gobble up a thou or two fast.
As cases are used, they become nicked almost imperceptably.Fitted necks
go down hill fast then. Chamfering without polishing off the secondary
burr that is created is even enough to do this. I doubt that ejectors
and fitted necks get along for any length of time. A barrel I have
with .264 neck and used .2635 loaded rounds , now uses a .2605
loaded round and has not declined at all. The little nicks, that
you can barely feel, gobble up a thou or two fast.
Boyd Allen
Active member
Bob,
.0035 neck clearance gives the same accuracy as .0005 did (same barrel and chamber)? Very interesting...do the necks seem to get over worked as compared with those in the .001 to .002 range?
Everyone else,
Thanks for the information.
.0035 neck clearance gives the same accuracy as .0005 did (same barrel and chamber)? Very interesting...do the necks seem to get over worked as compared with those in the .001 to .002 range?
Everyone else,
Thanks for the information.
R
RayfromTX
Guest
Art-
That was some list. Thank you for sharing that with us.
That was some list. Thank you for sharing that with us.
necks
I've used fited necks and up to .0015 over a loaded round. The fited necks were used in the early days using a full case of scotish 4895 and Metgers 7 OG bullets (wish I still had some of both). I shoot a wide range of bullets, some as big as .244+ so that would give me only about .0005 clearance. I've noticed when I shoot them if I pull the loaded round the necks will show a scuffed ring at the preasure ring. I also enjoyed this thread.
I've used fited necks and up to .0015 over a loaded round. The fited necks were used in the early days using a full case of scotish 4895 and Metgers 7 OG bullets (wish I still had some of both). I shoot a wide range of bullets, some as big as .244+ so that would give me only about .0005 clearance. I've noticed when I shoot them if I pull the loaded round the necks will show a scuffed ring at the preasure ring. I also enjoyed this thread.
Gene Beggs
Active member
Boyd, this has been a most interesting thread. You did a good thing for us all by opening the subject.
During my twenty something years in bechrest, I have tried just about everything known to man as far as neck clearance, neck tension, seating depth, etc., is concerned, but just when I think I have been everywhere, something new pops up. I'm always happy to share my findings with others. Keep the good discussion going.
Best regards,
Gene Beggs
During my twenty something years in bechrest, I have tried just about everything known to man as far as neck clearance, neck tension, seating depth, etc., is concerned, but just when I think I have been everywhere, something new pops up. I'm always happy to share my findings with others. Keep the good discussion going.
Best regards,
Gene Beggs
Both of my 30BR's and my 30 WolfPup work best with around .003 (or a bit more) neck clearance. This .003 is over the pressure ring on the 30BR's and over the shank of the bullet on the 30 WolfPup (the pressure ring is well below the neck-shoulder junction on that particular cartridge).
This morning, I ran a series of neck clearance tests with my LV 30BR. I had previously made up some test cases for this exact situation when I had made cases for this rifle. Using a proven good load as a baseline, I shot two 5 shot groups as the 'control'. The 'control' cases are from the 50 made initially and have .003 neck clearance. Then, I fired 5 shot groups with cases having .0005, .001, .0015, .002 and .0025 neck clearance. Then, I cleaned the rifle, fired two foulers and repeated my two 5 shot groups using the same cases as I did in the 'control' groups.
The 'control' cases again showed the best groups. I wouldn't want to have to live off the difference between .0025 and .003..... but all things considered, the .003's just give better overall results for me in this gun. I haven't gone past .003 with this rig yet. I have some cases ready with .0035 and .004 for this rifle, but the wind had started to get hinky enough for me call it a day. Three hours of relative calm in The Forbidden Zone on a mid-July morning is already pushing my luck.
Two weekends ago, I used my other 30BR and fired a 250-24X at an IBS registered event at Holmen, Wi. The cases I used in that gun have .004 neck clearance, have been fired in excess of 50 times each, are sized with a bushing .005 under what a loaded round measures and are annealed regularly. I doubt that with that much clearance and sizing that you'd see this much case life without regular annealing.
I think a lot of 'what works best' for neck clearance, in any individual application, has more to do with how much, and where, the cases are sized as anything...in other words, how a sized case fits the chamber when it's in what I term the 'potential' state. 'Potential' case fit includes how the sized case fits dimensionally in the chamber, the amount (if any) that the bullet is jammed and the relationship of the case head to the bolt face. Stir in bolt-to-reciever clearance, whether the bolt has a plunger style ejector..... blah, blah, blah.
But you don't have to puzzle over this too long before it becomes clear that in some situations, the case neck will be in contact with the chamber neck..at least to some small degree. And that may or may not be a deal breaker, either.
I'm sure not saying any of this will be the same in a 6PPC, 6Beggs, 22PPC-.100, 22 Beggs, etc. Hell....I'm not even sure it would be the same for other peoples .30 cal. stuff. I've just taken the position that I'll let the targets tell me and ponder the 'why's' after.
For what it's worth. -Al
This morning, I ran a series of neck clearance tests with my LV 30BR. I had previously made up some test cases for this exact situation when I had made cases for this rifle. Using a proven good load as a baseline, I shot two 5 shot groups as the 'control'. The 'control' cases are from the 50 made initially and have .003 neck clearance. Then, I fired 5 shot groups with cases having .0005, .001, .0015, .002 and .0025 neck clearance. Then, I cleaned the rifle, fired two foulers and repeated my two 5 shot groups using the same cases as I did in the 'control' groups.
The 'control' cases again showed the best groups. I wouldn't want to have to live off the difference between .0025 and .003..... but all things considered, the .003's just give better overall results for me in this gun. I haven't gone past .003 with this rig yet. I have some cases ready with .0035 and .004 for this rifle, but the wind had started to get hinky enough for me call it a day. Three hours of relative calm in The Forbidden Zone on a mid-July morning is already pushing my luck.
Two weekends ago, I used my other 30BR and fired a 250-24X at an IBS registered event at Holmen, Wi. The cases I used in that gun have .004 neck clearance, have been fired in excess of 50 times each, are sized with a bushing .005 under what a loaded round measures and are annealed regularly. I doubt that with that much clearance and sizing that you'd see this much case life without regular annealing.
I think a lot of 'what works best' for neck clearance, in any individual application, has more to do with how much, and where, the cases are sized as anything...in other words, how a sized case fits the chamber when it's in what I term the 'potential' state. 'Potential' case fit includes how the sized case fits dimensionally in the chamber, the amount (if any) that the bullet is jammed and the relationship of the case head to the bolt face. Stir in bolt-to-reciever clearance, whether the bolt has a plunger style ejector..... blah, blah, blah.
But you don't have to puzzle over this too long before it becomes clear that in some situations, the case neck will be in contact with the chamber neck..at least to some small degree. And that may or may not be a deal breaker, either.
I'm sure not saying any of this will be the same in a 6PPC, 6Beggs, 22PPC-.100, 22 Beggs, etc.
Hell....I'm not even sure it would be the same for other peoples .30 cal. stuff. I've just taken the position that I'll let the targets tell me and ponder the 'why's' after. For what it's worth. -Al
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