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From: boyd@mailer.cc.fsu.edu (Mickey Boyd)
Newsgroups: rec.guns
Subject: To trim or not to trim auto pistol brass
Message-ID: <35600@mimsy.umd.edu>
Date: 14 Jun 91 00:56:31 GMT
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In article <35569@mimsy.umd.edu>, nstar!bluemoon!jamaass@iuvax.cs.indiana.edu (Jeffrey A. Maass) writes:
#
#Is it necessary to trim 9mm/.45ACP brass? I'd been told that
#the non-rifle cases won't need trimmed.

Most auto pistol brass is really short.  It is unlikely that you will ever
need to trim them, and if you do it is likely that the brass is really 
stretched and should be discarded.  I occasionally check with my calipers,
but I have never found a long .45ACP case (not even close), even after 
being loaded 5 or 6 times.  

By the way, this brings up an interesting point.  If the 9mm/.45ACP is 
supposed to headspace on the case mouth, and if the vast majority of the 
brass made in these calibers is too short to make this possible, what is the
primary force that  holds the case against the slide face?  I personally
believe it is the extractor (since lots of other really smart folks do :-).
However, this may also imply that by using "correctly" sized and lengthed
brass you may get more consistancy (ie accuracy, never mind where you would
get this brass).  Anybody tried this?
-- 
             Mickey R. Boyd          |  "God is a comedian playing to an 
          FSU Computer Science       |      audience too afraid to laugh."
        Technical Support Group      |
      email:  boyd@fsucs.cs.fsu.edu  |                  - Voltaire