Trimming within 0.003"

af_newbie

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Hi there,

I'm reloading .308
My Speer manual says to trim to 2.005"

I trimmed all cases in my batch. But I'm getting inconsistent
results. Most cases got trimmed to 2.005", but I had few that
were between 2.002"-2.004"

I'm using RCBS manual trimmer. I used RBCS case master and hand
caliper to check the length.

My question is this:

Should I throw out the cases that are not the exact length but are
within 0.003"?

How accurate are you with your trimming equipment?

Are you getting consistent trim length?
 
I certainly wouldn't worry about it....don't throw any out, they're gonna grow back when you fire 'em.
Also...you might find some variation just from chamfering.
Big picture - unless you're doing some super-accuracy stuff, a thou either way ain't gonna affect anything.

IMO.
 
Trimming

Most cases have more neck than necessary and since they headspace on the shoulder (308) length of neck is not critical. If you wanted to you could trim them all to the length of your shortest cases but if there were only a couple I wouldn't. Unless you have a very minimum length chamber or were shooting a match grade rifle I would not worry about it. Some factory brass is .005 to .007 shorter than the book trim length.
Carry on!
 
Being too short is no big deal with a cartridge that headspaces on the shoulder, belt or rim. Even with cartidges that headspace on the case mouth, a few thou short is ok.

It's too long that is the problem. If sufficiently long, the case mouth can be pinched in the throat when chambered and pressures can go through the roof.
 
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