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Minimum Brass Trim Length

.257roberts.257roberts Member Posts: 54 ✭✭
edited August 2008 in Perry Shooter Competition Shooting and Reloading Forum
Hello Everybody, How much below book specs can you trim once fired rifle brass? The manual states 2.205" for .220 Swift. A buddy said to trim 10 thousanths under what the books say. My problem is half the brass i have accumulated is shorter than that already. What I can trim I've trimmed to 2.195", what can I do with the rest? I would like to keep everything equal. Thanks Robert
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Comments

  • Tailgunner1954Tailgunner1954 Member Posts: 7,734 ✭✭
    edited November -1
    General rule of thumb is that Trim-To is .010 below Max length, and that (spec) minimum is .010 below "trim-to" length.

    That said, as long as your reasonably close to spec, load and go (with the swift you'll be needing to trim even the short ones in a couple more firings). Wait until a couple of them reach the "max length", than cut them all to somewhere between min and "trim to"
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  • .257roberts.257roberts Member Posts: 54 ✭✭
    edited November -1
    Should I trim them all to 10 thousandths below the "trim to length", or just accept the accuracy they achieve until they grow?
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  • jonkjonk Member Posts: 10,121
    edited November -1
    I wouldn't worry about it. Without a measure of your particular chamber (like with a chamber cast) it is all theory anyhow- book specs may not quite apply to your rifle. For instance- I have an 8mm Mauser I made a chamber cast of. The neck is about .05" longer than spec would dictate. If you are trimming to spec, if a few are slightly shorter, I wouldn't worry; odds are you won't see any difference and it isn't dangerous anyhow.
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  • mrbrucemrbruce Member Posts: 3,374
    edited November -1
    The only REAL reason to trim brass is when it's to long for the chamber and it starts to pinch.
    I open up the primer pocket hole and stick a bore scope into the case when it's chambered to check for true length.........
    Sinclair sells a sintered lead plug you can use in a trimmed case to tell the actual length...
    Anything else is just guessing what your chamber calls for......
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