6PPC Neck Thickness

[cruisor]

Hello,

I just purchased a short range BR rifle and the neck diameter is .268. The fellow I bought it from said there are other folks using this and are very successful. Is any one on the forum doing this? I'd like to hear from you. It's been quite awhile since I've shot BR and I'm really excited to get back at it again.

Lee

 

[ttfreestyle]

I have 262 as well as 268. Accuracy is great with both. 268 is easier to prep in my opinion.

 

[rayporter]

send me a pm.

we have a shoot coming up august 5 in arkasas.

 

[INShooter]

I changed from a .262 to a .268 three years ago. I don't think there is any accuracy difference but there is a big difference in turning necks. Also able to maintain more neck tension. I turn necks to .0113 for the bullets I use.

 

[varminthunter1]

Hi Lee.

Here is a informative thread on 262 vs 268.

http://benchrest.com/showthread.php?74797-6ppc-reamer

Jeff

 

[Tim s]

Well......here is some info for you.
I have been to IBS matches and sat in on Jack Neary's loading/testing seminar and Q&A.
Jack in a former USA team member, sponsered by Vitouvoori.....pretty damn good shooter.
Among his principle topics for discussion is his theory for " cut them thin to win". Most guys shoot, say, a .262" neck and trim to, say, .085". That is generally what I do.
Jack says you should go down to .082", states you have far more consistant neck tension and states without equivication, if he sits down to shoot groups with thin necks and a couple thick ones thrown in, he can ID them after firing.
You cannot believe the testing methodology this guy employs.

 

[Tim Singleton]

Well......here is some info for you.
I have been to IBS matches and sat in on Jack Neary's loading/testing seminar and Q&A.
Jack in a former USA team member, sponsered by Vitouvoori.....pretty damn good shooter.
Among his principle topics for discussion is his theory for " cut them thin to win". Most guys shoot, say, a .262" neck and trim to, say, .085". That is generally what I do.
Jack says you should go down to .082", states you have far more consistant neck tension and states without equivication, if he sits down to shoot groups with thin necks and a couple thick ones thrown in, he can ID them after firing.
You cannot believe the testing methodology this guy employs.

I know this is an older post. But I'll comment anyway. The point Jack is making is total neck to chamber clearance. When in his case I think he shoots a 262 he cut his necks thinner to gain more clearance. That is the point of that segment of his clinic. More chamber to neck clearance than what has been used in older days of PPC shooting
Aim for .0025 to .003 total clearance

 

[Tim Singleton]

A lot of top guys shoot a .268 there are a lot that shoot .262, .263
I shoot a .268 and have the necks turned to .011. Loads round measures .2653 to .2655 depending on the bullet

With the top quality Lapua brass as long as you at least skim cut it
It will shoot. some shoot a 269 NK for just a skim cut

 

[Tim s]

A lot of top guys shoot a .268 there are a lot that shoot .262, .263
I shoot a .268 and have the necks turned to .011. Loads round measures .2653 to .2655 depending on the bullet

With the top quality Lapua brass as long as you at least skim cut it
It will shoot. some shoot a 269 NK for just a skim cut

Well I will tell you that as part of the talk I heard him give, it was discussed, the topic of

I know this is an older post. But I'll comment anyway. The point Jack is making is total neck to chamber clearance. When in his case he shoots a 262 he cut his necks thinner to gain more clearance. That is the point of that segment of his clinic. More chamber to neck clearance than what has been used in older days of PPC shooting
Aim for .0025 to .003 total clearance

At the risk of sounding like I am talking for Jack, that was exactly NOT the point he was making.
Now it may,very well be he has changed his thinking but at the presentation I was present at, it lead to the very question of bigger necks and the "no turn" and/or "little turn" approach , it had as much to do with thinner necks as anything, not clearence. I still take this to mean thin necks yield less varience between necks which has more to it than a clearence issue.
I suspect, however, with the fact that LT 32 has come on pretty strong and no doubt requiring less neck tension than 133 the yield from this thinking may now be more powder specific, but since Jack is sponsored by VV I suspect he won't be commenting on that aspect.

 

[Tim Singleton]

straight from Jack
http://www.nbrsa.org/PrecisionRifleman/Issues/2016/03_2016_online.pdf

 

[Tim s]

straight from Jack
http://www.nbrsa.org/PrecisionRifleman/Issues/2016/03_2016_online.pdf

Yep, pretty much as remembered. You'll note, no where in there is it stated the approach was only about clearance.
You think, maybe, these guys simply want to indulge in unneccessary neck turning ????

 

[Tim Singleton]

Yep, pretty much as remembered. You'll note, no where in there is it stated the approach was only about clearance.
You think, maybe, these guys simply want to indulge in unneccessary neck turning ????

Didn't you read the article? No where does he mention any other reason than clearance. In regards to the turn thin to win
Obviously with a 262 or such chamber the brass has to be turned

excerpt from article

I suggests that if you have time, to forget about the thousandth or 1⁄2-thousandth total clearance, try to have your loaded round to have .002 or more clearance. I current- ly use a.263 neck with a boat tail
bullet. My loaded rounds measure .2602 at the neck. Having more clearance is going to help you

 

[Tim Singleton]

 

[Tim s]

You might wish to ponder why he is among the guys that use those neck dimensions....something you are simply disregarding,
I read the piece, I heard it first person, as did I hear WHY the thin part.
If you see Jack, perhaps inquire.

 

[Tim Singleton]

I've loaded on the next bench beside Jack and competed with him several times
I fail to see how you don't get what he is saying
But oh well. I've tried

 

[Curious]

I've loaded on the next bench beside Jack and competed with him several times
I fail to see how you don't get what he is saying
But oh well. I've tried

Me to.

Watching the video clip its clear to see Jack is referring to neck clearance in the chamber. The story he tells is about the thicker brass (with less neck clearance) not shooting so well is as clear as it needs to be. He is suggesting running 2-3 thou of neck clearance as opposed to the older thinking of much less.

3-4 tenths difference in actual neck wall thickness wont affect neck tension at all in terms of consistency so long as everything is the same thickness and the brass is all in the same state of anneal.

 

[Kiwi Greg]

I have two reamers, .269 & .263

I chambered a couple with the .269 & they shot great.

Then I got a couple more chambered with the .263, they shot ok

I tracked it down to possibly not enough neck thickness & availible tension because of it.

The new lot of N133 I have takes up more room in the case & tended to push the projectile out of the case because the necks couldn't hold them in there, very frustrating

I got them both rechambered with the .269 reamer & now they shoot great too

 

[Tim s]

I've loaded on the next bench beside Jack and competed with him several times
I fail to see how you don't get what he is saying
But oh well. I've tried

The next time you see him, ask him why HE continues to shoot a tighter neck ?
Make sure you follow up with questions as to whether he has opinions on the consistancy of sizing and relative work hardening of thicker or thinner necks.
With all due respect you're failing to see a few things.
When you're done with that excercise, contact, who you may believe is the single best BR smith in the USA and ask the same series of questions.....I have. You will find the responses enlightening.