When is a gun too hot?

[358minus1]

20 years as a ferrous metallurgist....

I have been a ferrous metallurgist for 20 years. Gun barrels are definitiely heat treated for increase the strength, wear resistance and hardness of the steel. Non stainless barrels are generally made from medium carbon steels such as 1040 or 4140 and are heat treated to about Rockwell C 40-45. Stainless steel barrels are also heat treated to the same approximate hardness level and are generally made from steels such at 17-4PH and 420 stainless steels. The final step in the heat treatment process involves tempering the steel somewhere around 1000 degrees Fahrenhiet for a few hours. This temperature must be exceeded before you do any significant damage to the steel's mechanical properties. However, the steel's wear properties can deteriorate somewhat above 500-600F. So a barrel that shoots 200 rounds in 2 minutes twice a week might wear out slightly faster than a barrel that fires 200 rounds over a couple of hours twice a week. If you consistantly shoot your gun enough to cause metallurgical damage to the barrel, you are likely damaging it in many other ways, such as burning up all your oil lubrication.

You really can't damage the barrel from shooting it in what most of us would consider heavy usage.

100 rounds in 45 minutes is no where near damaging your gun. Shoot away!!!

 

[BlindJustice]

Thanks 358minus1.

A Gunner's Mate CPO on my second ship, DD-971 allowed me and I was the
only non-gunners mate during this session on the fantail at sea
to fire an M60. He told me before I had my turn with a 100 rd belt of
7.62 "A good B.A.R. man in WWII could flick his finger and fire a
single shot when he wanted to even if the weapon was in full auto
mode. Well, I accomplished that about the 3rd flick of the finger
then I did the rest of the belt in 5-10 rd bursts, Then the
lowest ranked gunners mate got his turn He ripped an entire belt
and the Chief was yelling at him to SLow that Weapon down.
Chief Scotty then had them swap out the barrel. Problem is with
long sustained bursts, the area in the leading edge of the chamber
where the bullet comes out of the case - that's the spot that
gets too hot and that area can actually be eroded away. Same
thing can happen with bolt action magnums that have too much
powder behind the bullet, .220 Swift, as well as .264 Win
Magnum are a couple that come to mind that are known to
have short barrel life.

Since I only have two mags for my CZ 75B it doesn't get
over fairly warm until about the 4th reloading of both mags.
I recall reading the CZ 75B although it has cast frame and slide,
the barrels are hammer forged and heat treated.

my most rounds fired in a single session with my S&W Model
60-15 - it's the '97 or later chambered for .357 Mag., the
Magnum J-frame has a little more metal ahead of the cylinder
and perhaps the top 'strap.' I was shooting .38 special and
.38 Spcl +P one day reloading the 5 shooter as quickly as a
sustained rate allowed and by 55-60 rds the
cylinder was a bit too hot too reload without being
careful for a oh, that is hot if my fingers touched the metal
cylinder.

Even though I have 5 magazines for my 1911 it has the
slidecovering the barrel and enough mass to not get too warm
in a 150-200 rd session in approx. 30-35 minutes.
I wondered about it once, when the slide was back and touched
the exposed barrel, ouch. won't do that again.

Randall