300 wsm hard chambering

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6724

New member
i have a cz model 3 in 300wsm. i started with 100 new winchester brass, i also have an assortment of range brass. the winchester has been fired 2 to 3 times. brass fired in the cz and reloaded fit very tight, a little too tight for a hunting gun. it is hard to close the bolt. while my other bolt rifles with neck sized ammo are a snug fit, this is beyond snug. it has nothing to do with the case length nor the bullet seating depth.
i have tried to full length size them, but that did not help. i screwed the die in farther, when the brass is in the sizing die the shell holder touches the die. effort to size is more than most of my other calibers.

i had thought that i would just put the size die in the lathe and turn a few thousandths off of it. but, of late i am thinking that the problem might not be the die, but the brass itself. perhaps the brass is springing back? a fired case chambers easier than a sized one, but still fits snug.

i swear there was a thread about this issue before, but i cannot find it.

the dies are hornady, they are far from my favorite brand of dies.
 
That WSM brass can be hard, especially if its been fired 3 times. Its probably time to anneal your bass. When thats done, I would trim to length then set your FL sizer die to cam over at full stroke. You wont get a true FL size if your die simply touches the shell plate at full stroke. That shell plate needs to touch and have some cam over on the press to get a consistent size. Don't forget to lube the case necks when sizing.
 
You might try turning the die body slightly deeper into the press.(a little more cam over) you can also surface grind a couple thousands off the top of the shell holder.
 
Originally Posted By: 6724
I have a CZ model 3 in 300 WSM. I started with 100 new Winchester brass, I also have an assortment of range brass. The Winchester has been fired 2 to 3 times. Brass fired in the CZ and reloaded fit very tight, a little too tight for a hunting gun. it is hard to close the bolt. while my other bolt rifles with neck sized ammo are a snug fit, this is beyond snug. it has nothing to do with the case length nor the bullet seating depth.
I have tried to full length size them, but that did not help. I screwed the die in farther, when the brass is in the sizing die the shell holder touches the die. Effort to size is more than most of my other calibers.

I had thought that I would just put the size die in the lathe and turn a few thousandths off of it. but, of late I am thinking that the problem might not be the die, but the brass itself. Perhaps the brass is springing back? A fired case chambers easier than a sized one, but still fits snug.

I swear there was a thread about this issue before, but i cannot find it.

The dies are Hornady. They are far from my favorite brand of dies.

I would start with a better set of dies - I have a bunch of problems with their standard dies. I bought a set of 264 WM and a new, unfired case would not go more than 1/2 of the way into the sizing die, no matter what.

(Their 50-BMG dies are beautiful - but they should be for the price, a 3 dies set is ~$400).

That said... When you FL size a case, you squeeze the body, and the shoulder moves slightly forwards - that is why the FL sized cases chamber harder than the fired cases or neck sized cases. It gets worser when you use a FL dies to partially size the case, cuz the shoulder get s pushed forwards, but then it doesn't get pushed back.

If you do like the other guys suggested, and turn the FL die down a 1/4 past when it hits the shell holder (but I think you said you have done this)... and you still have problems, try running the case up into the die TWICE (double sizing)... that might help.

If that doesn't do it...

1 - NEVER "grind" the bottom of a die. Use a piece of #400 Silicone carbide "Wet-n-dry" paper, on a piece of glass or other flat surface, and with a little oil.
Lap the shell holder down, with figure "8" motions. Try it every 3 or 4 minutes.

2 - Annealing the shoulders will also help.

3 - You can also try a Redding Body die.

This is a common problem with cases that have large shoulders and steep shoulder angles.
 
screwing the die in more will not change anything, the die and shell holder cannot get any closer. the shellholder is in contact with the die at the top of the stroke. it cams over plenty.

i have a few sets of hornady dies in other calibers but i really do not care for them.

i will first try to anneal the cases and see where that leads. if that does not do it, i think i will try a different set of dies.
 
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