I've recently purchased my first AR (bushy 20" hbar), and I find that after emptying (not rapid fire) a 30 round mag the barrel gets quite hot.  I'm new to the AR15 scene, but not to firearms in general.  I've been a handgun and reloading enthusiast for years.  In all my time shooting, though, it seems that none of my other firearms collects quite as much heat as my new bushy.  That surprises me considering that I've shot a wide variety of calibers including much larger calibers.  My question is this:  How many rounds/mags do most of you shoot (not rapid fire, just at a comfortable aim and shoot pace) before allowing for a cooling period?  

Thanks in advance, and i hope that this isn't too stupid of an AR-newb question.

*edited to change "clip" to "mag"...thanks shadowblade
*

The barrels do get hot.  No need to worry about it unless it starts glowing [:)].  

I generally pause to let mine cool down for a second or two between mags (BTW - not clips - they'll jump on you for that around here).  Then I let it cool down before I put it into the case because it was a pain to clean the melted plastic off of my barrel that last time...

If you're worried about possibly damaging the barrel, don't be. In the Army we had the M16A1, which would get so hot after only 1 magazine on full-auto, you'd have to hold it by the front of the magazine well. I've shot hundreds of rounds going full-auto, and it never even fazed it. Had to wait a WHILE before you could touch the barrel, but what the hell...

it's normal for the barrel to get hot, when you say that it gets hotter then other rifles you have, ......a lot of that may have to do with the rifling ratio and barrel length..the faster the twist, the more heat it generates.

When Im done shooting mine you cant hold on to the free float handguard...  Grip it and rip it....   Guess thats why i have the bipod....

No need to worry.  Have fun..

Prosise

I’ve never really stopped to let an AR or M16 cool; if I happen to stop shooing I guess they have a chance to cool. I did melt a gas tube once; two consecutive beta mags seem to cause too much heat/pressure. The gas tube looked like a McDonalds straw after you hold a lighter under it, real mess, the barrel is still fine, although I don’t know if it is fit for a match. The upper is all Bushmaster 14.5-inch heavy-barrel.

Best Regards, C

The manual that came with my RRA CAR A2M4  (U.S. Army TM9-1005-249-10) says "Sustained rate of fire for the M16/M16A1 Rifle is 12-15 rounds per minute.  This is the actual rate of fire that a weapon can continue to deliver for an indefinite length of time without serious overheating."

Same manual goes on to say, "Firing 140 rounds, rapidly and continuously, will raise the temperature of the barrel to the COOKOFF POINT.  At this temperature, any live round remaining in the chamber for any reason may cook off (detonate) in as short a period as 10 seconds."

Is the Army being paranoid?  I dunno.  When I shoot, one round every five seconds is plenty fast for me!  But then again, my AR is waayyyy more accurate than I am, so what do I know?  

Mike Sigman
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I usually shoot one round per 2.5 seconds and it DOES get hot after shooting 2 magazines straight.

Then I let this guy cool down before I can hold the barrel with my bare hands. I recently added SIR to it and it DOES cool down faster.