Cases too large near the web

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Ryan.M.Anderson

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Quick question for the reloading gurus.

I have an AI and a TRG. I had the TRG first and shot a bunch of lapua 308 through it. I got the AI and after fighting with some hornady brass decided to switch over to my Lapua. Ran it all through the fl sizer (properly set up and all that good stuff).

Anyways I determined that near the webbing the case is about .003 larger than the hornady. It makes it a little sticky to chamber/extract but nothing serious. I tested my theory with a blue sharpie and it is definitely at the case head end and not the mouth - clear ring near the webbing.

My theory is that the TRGs chamber is just a smidge looser than the AI.

Will i have any issues with this?
 
How do the dimensions compare to the 308 SAAMI Drawing? Measuring a fired case will give you an estimate of the chamber diameter. Adding 0.001" to what the fired case measures is the usual trick up near the neck. Near the base the difference may be more than that. As a rule I would not mix brands of brass or mix the brass between different guns after the first firing. I have two guns chambered in the same .264 WM, and after firing and full length resizing (not just bumping), the cartridge from either gun will not fit the other. The barrel was replaced on one gun, and even then the fired brass was still not interchangeable.
 
Chamber dimensions can vary a bit, even when they all conform to SAAMI specs.

I am religious about keeping my brass separate when I have more than one rifle in the
same chambering.

I have several 308 Norma Mags, and have separate dies sets for each rifle. One of these
rifles has a chamber so snug that unless I use the die that sizes to the smallest dimensions,
[not a small base die, though] the sized case will NOT enter it's chamber.

If I measure a sized case just above the belt, this dies sizes to .511", whereas the others will only size to .5125"

I have had several rifles over the years with these "snug" chambers, and it can be interesting
to find dies that size enough so the brass fired in another rifle will chamber after sizing. I try to
avoid Small Base dies wherever possible.

Regards, Dave.
 
Pause at the top of the ram stroke for a few seconds, this reduces brass spring back after sizing.

Also remember dies can vary in size, example, I have a standard Lee .223 full length die that reduces the case diameter "MORE" than my RCBS small base die does.
 
I fired 70 today at the range and they all extracted after firing with no issues.

I will keep them seperate going forward - we all know what it is like when the new toy arrives.
 
bigedp51 said:
Pause at the top of the ram stroke for a few seconds, this reduces brass spring back after sizing.

Also remember dies can vary in size, example, I have a standard Lee .223 full length die that reduces the case diameter "MORE" than my RCBS small base die does.
Click to expand...

It is perfectly normal to have different dies working differently.
All that we touch in our hobby is governed by standards of manufacture and they have manufacturing tolerances that at times affect the performance we seek.
For example rifle chambers, chambering reamers, empty cases, bullet diameters, powder burn rates, barrel groove and land diameters etc.
It's a wonder that we are still alive ! hahaha

Oh yea to the OP, segregate your brass and you will not have problems.
BB
 
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