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I'm at the range today and the guy next to me loads a betamag onto is AK-103 and bump fires to whole drum.  Then he immediately sprays a lubricant all over the barrel as steam comes off of it.
Was this to cool down the barrel?  Obviously.  Does it help or hurt though?  What happens in a melt down situation?  Does anyone have a pic of this malfunction?

The reason I ask:  I learned how to bump fire my AR today and I am concerned that I will overheat the upper.

sounds to me like he was just trying to show off.
why would you bump fire and entire drum of ammo?
i was taught to shoot in burst when shooting full auto.
since he had to bump fire, instead of "dumping it" (full auto) i'd say he was just showing off.

What a great way to fuck up the chemical structure of the steel.
"Sure, let me shoot 120 rounds in a few seconds and then put some liquid on it" Arn't me smot?

I was kind of wondering about this myself.  I fired 300 rounds through my new colt m4 at the range the other day in approximately forty minutes, it was breaking in the finish and it got very hot and smoked.  I figure that it can handle this heat though right?  I mean full auto has got to make them much hotter than that.

I assume taking hot metal and spraying cold liquid on it like that guy did, would just cause fractures and cracks in the metal, like pouring water on ice.

[noclue]

Bump firing a BETA is showing off; I don’t see any other reason for it.

Hosing it down with cool (relatively) liquid anything is just stupid.

Maybe he’s trying to make a point; apparently he can afford to.

Sustained rate of fire for the M16 I believe is 12 to 15 rounds, so bump your weapon in about ten round bursts and you should be fine. More than that, too much pressure will build in the system and the first thing to go will probably be the gas tube. The AK does not have a impingement gas system and its system is much hardier than that of the AR. I don’t know if bumping 100 rounds out of the AK will really hurt it; 75 rounds of 7.62 doesn’t seem to at all. And I do know two BETA mags will melt most gas tubes in a M16.

Best regards, J

BREAKING IN THE FINISH?????????????????

AIR COOLING WITH AN AIR HOSE. I THINK ALL AK's SHOULD HAVE THE METAL (ANEALED) WITH COLD LIQUID!
JACK

I wonder how many rifles have been destroyed by use in the rain. [rolleyes]

To much pressure will build in the system???  You must check the setting of the pressure relief valve in your rifle,it is obviously set incorrectly!!  

Don't confuse rain during firing, opposed to letting it get supper heated then drenching it with cold fluid, that is how metal gets ruined. Non of your barrel makers use anything but air hoses to cool the weapons down for very good reasons.
It can all be found in your metalergy ref. books!
Jack

Thank you JTR8541.  That was exactly the information I was looking for.
I always get information on this site that saves me time and money.  Its worth my $20.00 membership.
Thanks.

they call it an Air-Cooled Rifle for a reason.


That guy was obviously trying to look cool, and like he knew what he was doing...

If he had common sense, he'd know that he'd be SEVERLY fucking up his gun by trying to cool it down faster that it is supposed to.


Once you fire the rounds, all the damage possible is already done. You can't redeem it by cooling it down. Cooling it down rapidly will warp the metal, and fuck up a few things.

shouldnt hurt it.

steel needs to be at least 600-700 deg celcius before quenching will change the metallurgy.

that is FUCKING hot.  now ruining the finish is another matter entirely, but fuck it, its an AK damnnit.

-Spaceman