RE: [OT] Re: Machine Guns (was Power Armour Weapons)

The M-60 problem was due to cook-offs (firing due to heat).  

Michael Brown

-----Original Message-----
From:	Imre A. Szabo 
Sent:	Wednesday, March 12, 2003 6:02 PM
To:	gzg-l@csua.berkeley.edu
Subject:	Re: [OT] Re: Machine Guns (was Power Armour Weapons)

> The 20mm gatling used by the USAF can still go through
> a large fraction its barrel life (half?) in one burst.
> The longer the burst the greater the wear. I imagine
> they use quite 'hot' loads in it to make up for its
> small calibre (20mm) and the lag as it takes time to
> spin up. Apparently they were going to move to a
> larger calibre weapon about thirty years ago but have
> not changed yet.

The AirForce version of the JSF is supposed be armed with a 25mm gatling
internal gattling.  There's a 25mm gattling pod for the other version of
the
JSF.

> A Shortage of brass was becoming a major concern for
> the Germans in WW II in part because almost all of
> their artillery used a brass case to seal the breech.
> They devolved steel cases for small arms and less
> successfully for artillery and were trying to develop
> breeches that would seal with bagged charges, I wonder
> why they did not just copy captured weapons though,
> mind you this was Nazi Germany so logic seems to go
> out of the window.

Steal cases tend to jam much more often then brass.  This especially
true in
weapons that get very hot, ie., machine guns and artillary that's being
fired a lot.

> I believe the M60 in Vietnam could 'run away' if it
> became too hot, the hot chamber cooking off rounds in
> the breech.

The M60 fires from an open bolt.  This means that the round is only in
the
breach for a fraction of a second before it was fired.	I suspect the
"run
away" problem had much more to do with:
1. Faulty ammunition that did not generate enough pressure to fully
cycle
the weapon.
2.  Defective parts in the weapon.
3. Or mostly likely, the weapon had been fired a lot before it's last
cleaning, and powder residue reduced the gas flow to the piston, thereby
preventing the weapon from fully cycling.

ias