From: John De Armond
Subject: Re: WARNING: Glocks and the use of lead
Organization: Dixie Communications Public Access.  The Mouth of the South.

baechler@lia.di.epfl.ch (Emmanuel Baechler) writes:

#I own a Glock 21 since four months. I fired 500 rounds with it and

#It has however one limitation: it does not support lead bullets. Last

#The gun is completely destroyed. The top of the chamber and a part of
#the top of the barrel has disappeared, the frame is torn away in small
#pieces and the slide is damaged too.

#A gunsmith examined the remains of the gun today. Its diagnosis is
#that the explosion was due to the use of lead. The guy didn't clean
#his gun since around 600 shots and the fouling in the barrel was
#absolutely clear. This lead finally slowed a bullet enough to cause a
#huge overpressure and the explosion. His comment is:

This is, of course, rubbish.  As a fairly advanced amateur gunsmith,
I can assure you that I could not look at a blown up gun and determine
what caused it to blow unless there was something obvious such as a plugged
barrel.  Leading most assuredly would not do it.

His use of lead bullets practically guarantees he was using reloads,
either of his own or commercial.  Any of the following could account
for a burst chamber:

*	Double charged.  The 9mm will hold a double charge.  Most every
	reloader has done this.  I know I have.  I have also bought
	commercial reloads that contained either double charges, no charge
	or the wrong powder, an occasion of which blew up the chamber of
	my M-14.

*	No powder.  This leaves a bullet stuck in the barrel and if the
	shooter doesn't notice it, can burst the barrel when the subsequent
	round is fired.

*	Compressed bullet.  If the misfeed pushes the bullet back into the
	case and the bullet is subsequently fired, extremely high pressure
	can develop.  Burst chambers HAVE been reported from this.

I don't like the plastic boing gun but my dislike for it detracts in no
way from the gun.  I suspect this "gunsmith" was either mistaken or
was not so careful to prevent his personal dislikes from entering
into his evaluation.

John

From: John De Armond
Subject: Pushing the max. (was Re: Hodgdon makes good!!)
Organization: Dixie Communications Public Access.  The Mouth of the South.

ses@hpfcla.fc.hp.com (Steven Speer) writes:

#I told Hodgdon about my head separation using the load we discussed here
#last week.  They were very appologetic and explained how the error had
#occurred.  They tested the loads in Smith & Wessons, another gun I can't
#remember and pressure barrels.  Their published max was fine in those (which
#correlates with some other data I have).  They then started hearing
#complaints about Glocks and a couple of other brands that were showing
#pressure signs.

(Steve, I'm not picking on you, just using your post as an excuse to
say something.)

Looks like it's time to revisit some reloading safety basics.

First and foremost in this context is that the maximum powder loads
listed in the reloading manuals should only be used as guides and not
taken as gospel.  Pouring in the maximum listed load right off the
bat is a good way to damage a gun.

The proper way to work up a "maximum" load is to start at the suggested
starting load and work up in about 5% increments, paying close
attention to pressure signs.  Pressure signs vary according to the type
of gun.  A bolt gun may first indicate pressure with a tight bolt or
hard extraction.  A revolver might indicate it by hard ejection or
a stuck cylinder.  Or it might be a flattened primer.  Whatever
the signs, if you work up slowly you will see the first signs before
gross signs such as punctured primers, torn rims or separated
cases manifest themselves.

If you have a chrono, a good indication of diminished returns is often
that the increase in velocity per unit increase in powder drops off.
If the gun is strong, such as with a bolt action, decreased delta
velocity may be a greatly leading indicator of excessive pressure.
It is also typical to see the standard deviation of the velocity
to decrease and then start back up again as the load starts to
become excessive.

This brings up a philosophical point.  I mention it because I've
run into several relative-new reloaders who bragged about how hot a
load they've developed for this or that gun.  This is, of course,
pointless and counter-productive.  I have yet to see a gun which
produces its best accuracy potential at the "max".  About all maximum
loads do is make big bangs and muzzle flashes, lots of recoil and
accelerates wear on the mechanism.

Just some thoughts from the reloading bench :-)

John