From: gmk@falstaff.tmc.edu (Geoff Kotzar)
Subject: Re: Accuracy lost by using 38 in .357 mag?
Organization: Case Western Reserve University

In article <38180@mimsy.umd.edu> n9020351@henson.cc.wwu.edu (James Douglas Del Vecchio) writes:
#
#  I was once wondering why _anyone_ would choose a medium frame 38
#when a .357 works just fine for 38 shooting?
#
#A friend told me that the longer chamber of the .357 causes the
#38 to have less accuracy and velocity than they would have using
#a gun built for the 38.   
#
#As the chamber is wider than the bore, is a signifcant amount of 
#gas leaked past a 38 slug before it makes the small distance to
#the bore?  Does this matter?
#
#Jim D

One reason for picking a .38 for .38 shooting over a .357 is that you
will eventually erode the chamber area in front of the .38 Spl case.
This results in difficult extraction of the longer .357 Mag cases. How
often does this happen? Not very. But it was either J.D. Jones or John
Taffin who reported it happening to them. My guess is that you would
have to shoot a lot of the .38 ammo, tens and tens of thousands of
rounds before it would become a problem.

Geoff Kotzar