Help me troubleshoot the problem 300 Win Mag Load

[cttbax]

Here is my problem.

When I seat the bullet, I can still move the bullet with my hands. There is very little tension in the neck to hold the bullet.

Here is my load info:
300 Win Mag
once fired (in my gun) Remington Peters Brass
FL sized, Trimmed to 2.60, inside and outside chamfered.
Bullet is a 200 Grain Sierra Match King HPBT.
Hornady one shot lube on the cases and necks-allowed to dry 10 minutes or so. Dies are LEE 300 Win Mag dies.

I have a box of Nosler brass, brand new. I seated 5 bullets with no problems. So I pulled my dies apart, cleaned the neck sizer, it did have some lube and brass gunk on it. Not bad, the dies are brand new, I have re sized 40 pieces of brass with them.
I Miced the neck sizer at its widest point: .305
Anyways, I am kinda stumped...

What am I doing wrong?

ETA: I found that the first 6 pieces I sized have this problem. I just loaded 10 more of the same batch with no problems. Could this be caused by the dirty neck sizer?

 

[22_250]

Re: Help me troubleshoot the problem 300 Win Mag Load

Neck sizer could be dirty, you can also turn the die in a little more for increased tension on the neck. I think the directions say 1/4 turn. I had the spindle turned down by .0001 on mine, so the collet can neck the brass down further to make sure I didn't have any creep in the bullets once seated. BTW I am using the lee collet dies.

 

[jwoolf]

Re: Help me troubleshoot the problem 300 Win Mag Load

Obviously, the issue is with the sizing operation somewhere.

Are you using a lee collet die or a standard die? Are you neck sizing only or FL sizing?

I've heard from some that when using a collet die, sometimes you have to turn the mandrel down a bit to tighten the neck tension.

I'm using a collet die but, I did not have to do that with my loads.

 

[cttbax]

Re: Help me troubleshoot the problem 300 Win Mag Load

I am using the collet die, full length sizing.

By turning the mandrel down you mean polish the neck sizing rod to make it a bit smaller?

 

[22_250]

Re: Help me troubleshoot the problem 300 Win Mag Load

Yep, you will need a good metal lathe... Lucky I have a friend with that and a cnc machine but any good machine shop should be able to help you. In lieu of that you could chuck the rod in a drill and polish it a bit not as accurate but would work.

 

[Grumulkin]

Re: Help me troubleshoot the problem 300 Win Mag L

<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: cttbax</div><div class="ubbcode-body">I am using the collet die, full length sizing.

By turning the mandrel down you mean polish the neck sizing rod to make it a bit smaller? </div></div>

You are certainly not the first to have loose bullets with the Lee Collet Die and mandrel polishing would be the solution.

By the way, though Lee's regular dies are fine and I love their Factory Crimp Die when a crimp is needed, in a couple of different cartridges, I got noticeably worse accuracy with cases sized with the Lee Collet Die when compared to regular neck sizing or full length sizing. Lee claims their collet die will produce the most accurate ammunition; it just ain't so.

 

[jrob300]

Re: Help me troubleshoot the problem 300 Win Mag L

<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: Grumulkin</div><div class="ubbcode-body">Lee claims their collet die will produce the most accurate ammunition; it just ain't so. </div></div>

For you.

I'm using a Lee collet die and loading ammo in the single digit ES range and sub-MOA to 1500 yds. Works for some.

BTW, I had to turn the mandrel *slightly* to get the neck tension I desired.

John