Newsgroups: rec.hunting
Date: Sun, 27 Apr 1997 12:44:02 GMT
From: "K. Karcich" <kkrh@troi.cc.rochester.edu>
Subject: Re: Low 30-06 Muzzle Velocities

In article <wNt5fFACplYzEwDD@salvage.demon.co.uk>,
Jonathan M. Spencer <jms@salvage.demon.co.uk> wrote:
>In article <1997Apr25.201439.4859@galileo.cc.rochester.edu>, "K.
>Karcich" <kkrh@troi.cc.rochester.edu> writes
>>In article <5jq4ai$rsi@senator-bedfellow.MIT.EDU>,
>
>[snbip]
>
>>To slug your barrel, you essentially drive a oversize soft lead slug between
>>two bore fitting rods, and expand it into the grooves.
>
>A better method is to use 'cerroafe', available from Brownells.  This is
>an alloy that you melt and pour into the plugged barrel from the action
>end.  You fill the chamber with the stuff.  It sets, and then contracts
>0.001" (and you remove it from the chamber & barrel).  You then have an
>exact mould of your chamber, throat, barel to measure and see what's
>going on.
>
>--Jonathan
>============================================================
>Jonathan Spencer -- forensic firearms examiner
>Mountjoy Research Centre, Durham, England, DH1 3UR
>tel: +44 191 386 6107   fax: +44 191 383 0686
>============================================================

Jonathan,

With due respect, some folks do not consider Cerrosafe superior to a plain
led slug, between two bore fitting brass rods. The claim is that Cerrosafe
does not just contract .001 and thats it. Its contraction is sometimes
uneven and somewhat unpredictable, depending on the batch. Veral Smith of
Lead Bullets Technology is one such person who does not like Cerrosafe,
and wants only a lead slug cast of chamber and bore, before he will use the
information to make a custom mould. His book on bullet casting and fitting
is a little jewel in my opinion, and well worth reading.

Personally, I use Cerrosafe when I want a chamber cast, cause its easier to
work with. But when I want the throat and the bore/groove dimensions I prefer
the soft lead slug.

Ken Karcich