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View Full Version : Hard bolt lift when fireforming



turkeynut
03-13-2013, 09:24 PM
I have 6ppc,.262nk,new lapua brass,fed primers,65gr v-max,loaded rounds measure .259,h322 26gr, bullets jammed/shoulders bumped/lightly lubed.The first 5 went smooth and the next few wasn't that bad but I could tell a differnce.I looked at the back of the brass and it was real shiney around the primer pockets.I mic the hard brass with a harrells bushing at 1.556 and the others was 1.554.I tried some new norma brass and it went perfect so, I don't know whats going on with the lapua brass.

markharp
03-13-2013, 09:58 PM
Is brass too long for chamber? I had to trim my new lapua to chamber in my 1.500 chamber.

turkeynut
03-13-2013, 10:09 PM
No, I had to trim after neck turning because they were to long.

turkeynut
03-14-2013, 02:12 PM
Got it figured it out.

Vern
03-14-2013, 04:40 PM
Turkeyhunt,
Its always better to trim before turning necks because the distance the neck is turned into the shoulder needs to be consistent

What did you find the problem to be?

turkeynut
03-14-2013, 09:48 PM
Vern,
I thought I figured it out by trimming a little more brass off at the neck/shoulder.I only did 3pcs that way and fired all without a single problem so, I cleaned the barrel/chamber and put it away.Well a buddy of mine wanted to see what was going on so, I loaded a few more and the bolt was hard to open.I just fireformed 50 in my wifes rifle without any problem.This is what puzzles me that I have to bump the shoulders back after the first firing to get the bolt to close easy.

turkeynut
03-14-2013, 09:55 PM
Rifle
Borden Rimock
Borden Robertson Stock
2 Bartlein lv 13.5tw
Stevens match reamer
I tried both barrles and the same thing happens.

Wilbur
03-15-2013, 04:59 AM
Best guess is that you are bumping them too much or too much powder. Ease up a bit on both as it's not REQUIRED to completely form in one firing. After the first firing, measure what you need to measure and go from there. Shoulder angles on new brass vs the angle of bump dies can trick you into false thinking/measurements.

abintx
03-15-2013, 11:16 AM
Vern,
I thought I figured it out by trimming a little more brass off at the neck/shoulder.I only did 3pcs that way and fired all without a single problem so, I cleaned the barrel/chamber and put it away.Well a buddy of mine wanted to see what was going on so, I loaded a few more and the bolt was hard to open.I just fireformed 50 in my wife's rifle without any problem.This is what puzzles me that I have to bump the shoulders back after the first firing to get the bolt to close easy.

Regardless of whether it's after the first firing or the tenth, you should be bumping the shoulders back .0005" to .0015" each time you FULL LENGTH resize.

You are Full Length resizing, right? Anything less than that is a half measure, and can cause all kinds of problems.

Before doing any 6PPC first-time neck-turning with new brass, I refer you to Tony Boyer's THE BOOK OF RIFLE ACCURACY, Chapter 13, page 143 and 145. Paragraphs Headspacing Before Neck Turning and Expanding The NECK.

Once you've headspaced and expanded the cases, you check overall length, then you trim, and then you turn.

[U]Read the details he takes you through before proceeding and you shouldn't have any problems in the future. :)

Vern
03-15-2013, 12:43 PM
If it means anything 1 batch of Lapua that I had needed to sized, bumped before I could fireform. A different batch the next year didnt require it.
Though that was bolt close before firing not after.

turkeynut
03-15-2013, 09:30 PM
I wasn't bumping the shoulders far enough and I backed the powder charge.I fired 20pcs without any problems so, thanks to Jim Borden and the rest of you guys for your help.I feel stupid that it was just a couple simple issues that I should have noticed.

Thanks
Joe