How many shots before cooling the barrel?

[DownrangeDuck]

1. I have an AR-10 and an AR-15, both configured as bench guns. The AR-10 has a 20" competition barrel/trigger/stock and Superlative Arms adjustable gas block. The AR-15 has a 18" competition barrel/trigger/stock and Superlative Arms adjustable gas block. How many shots should a guy fire before letting the barrel cool? I don't do any rapid fire shooting at all.

2. Also, I've heard some say "AR's like to run a little wet" meaning leave a little gun oil after cleaning. The company that built my AR-15 said "No, oil attracts dirt and you're inviting malfunctions". I could see that in a combat environment but I thoroughly clean my guns after shooting and they go back into the gun safe. They're clean when they go to the range, in a case. My longest range session is usually two hours.

Thanks,
DD

 

[LoonWulf]

uhhhh, when you mag runs empty?

I shoot a group, then let the gun cool, so how ever many rounds I want in that group.
If I'm not shooting groups I usually shoot till I'm out of on board ammo unless the gun I'm using strings really badly.

I've always run my ar wipped with a saturated eat which leaves a pretty decent film, but doesn't spit stuff. I haven't had an issue with them curding up tho even when run sloppy wet

 

[Skylerbone]

For your set, and I’m going to assume by “competition barrel” you mean Varmint or bull profile, perhaps with fluting, I’d say fire 10-round magazines, leave it locked open, check targets in your spotter, sip a bit of decaf to reset, then reload. 5 minutes between magazines is not an unreasonable period to wait especially where accuracy is the primary concern. Even better, bring a rimfire to shoot between.

I have never gone further than greasing lugs on my other rifles but my ARs are run with the bolt fully coated with FP-10 or CLP with an amount that is more than simply “soaked in” looking; the oil is pooled.

 

[troy fairweather]

I never liked getting barrels hot, so if I can hold the back of my hand on the barrel it's not to hot.

 

[skeeterfogger]

3 seconds between shots, 3-5 rounds then open to air a few minutes.

 

[FL-NC]

I use white lithium grease from auto zone as lube for moving parts. When debris gets in it, it doesn't act like oil and turn into mud. It stays greasy and the debris just hangs on for the ride.

 

[berettaprofessor]

That white lithium grease was fine, but it stays white and gets everywhere. May I suggest something more translucent and perhaps a better product like “Superlube”?

 

[DownrangeDuck]

For your set, and I’m going to assume by “competition barrel” you mean Varmint or bull profile, perhaps with fluting, I’d say fire 10-round magazines, leave it locked open, check targets in your spotter, sip a bit of decaf to reset, then reload. 5 minutes between magazines is not an unreasonable period to wait especially where accuracy is the primary concern. Even better, bring a rimfire to shoot between.

I have never gone further than greasing lugs on my other rifles but my ARs are run with the bolt fully coated with FP-10 or CLP with an amount that is more than simply “soaked in” looking; the oil is pooled.

Thanks for the information. Faxon heavy fluted, threaded barrel (.223 Wylde on the AR-15) ) with Faxon BCG. Being new to this, I'm sure glad I asked. I've been WAY over-shooting the barrel then. I shoot 10-round magazines and may shoot 3 to 4 mags before a break. I wished I'd asked earlier, trying to learn all this on my own...

So I'm curious about the M16 or M4 - Are they a heavier duty version of the civilian AR-15 (besides being selective fire)? I can't imagine a cease-fire in a firefight to allow everyone's barrels to cool!

Regarding the AR-10, Last time I shot it was with a buddy. We traded off shooting it. I would shoot a couple of 10-round mags, he would do the same, then repeat. So, way overshooting that one as well it sounds. It sure pays to ask...

Thanks again,
DD

 

[Varminterror]

Life is short and barrels are cheap. Especially AR barrels. Shoot how your application dictates.

 

[DownrangeDuck]

uhhhh, when you mag runs empty?

I shoot a group, then let the gun cool, so how ever many rounds I want in that group.
If I'm not shooting groups I usually shoot till I'm out of on board ammo unless the gun I'm using strings really badly.

I've always run my ar wipped with a saturated eat which leaves a pretty decent film, but doesn't spit stuff. I haven't had an issue with them curding up tho even when run sloppy wet

OK, it definitely sounds like I'm shooting too many rounds before pausing. What did you mean by "with a saturated eat"? And, what oil are you using? I know, THAT is a whole different discussion in itself.

Thanks,
DD

 

[DownrangeDuck]

I never liked getting barrels hot, so if I can hold the back of my hand on the barrel it's not to hot.

Ah, that makes sense. Yep, I'm shooting too many rounds for sure.

Thanks,
DD

 

[DownrangeDuck]

3 seconds between shots, 3-5 rounds then open to air a few minutes.

Wow, wished I'd asked soon. I'll definitely slow things down.

Thanks,
DD

 

[DownrangeDuck]

That white lithium grease was fine, but it stays white and gets everywhere. May I suggest something more translucent and perhaps a better product like “Superlube”?

FL-NC and BerattaProfessor: Regarding grease, I do have a tube of Mil-Comm TW25B https://www.amazon.com/Mil-Comm-Premium-1-5-Ounce-Synthetic-Lubricant/dp/B002T1ZW2E I assume that would work?

Thanks,
DD

 

[troy fairweather]

Downrangeduck I just noticed, welcome to THR.

 

[DownrangeDuck]

Downrangeduck I just noticed, welcome to THR.

Thanks!
DD

 

[jmr40]

It depends on the gun and outdoor temps. 22 rimfires I don't worry about. My 308, 30-06, and 6.5 CM rifles heat up a lot faster than my 223's. I always take at least 2 rifles and usually 3 or more with one being a 22. In cooler weather I can fire 3-5 shots through one, pick up the 22 and fire 10-20 rounds and the 1st rifle is cool enough to shoot again.

But in hot temps it takes a LOT longer for them to cool down, especially those above 223. It was 101 here today in the shade. Three weeks ago I was at a different range than my normal spot and after 20+ minutes the rifles still weren't as cool as I'd have liked. Outside temps were 100+ that day too. At my home range I can park right next to the bench where I'm shooting. I sometimes leave the engine running with the AC on high on really hot days and put the rifles in the front seat to cool off. That only takes a few minutes. That wasn't an option 3 weeks ago.

 

[DustyGmt]

I cant touch my bbl after 5 rds. It doesnt take much at all to heat up your bbl. I wouldn't charactarize the type of shooting you've described, 3-4 10 rd mag strings of fire as "way overshooting".

I'm surprised to hear some of the responses to this question. 3-5 rds then allow x amount of minutes for bbl to cool? Really?That is definitely not how I shoot my AR. I dont do constant mag dumps but it's not uncommon for me to shoot 10,20,30 in multiple sustained courses of fire.

OTOH, I dont own a competion rifle with a special bbl and it's possible shooting much more conservatively will preserve accuracy +bbl life...

 

[Slamfire]

I will bet that there are some here who remember this PS Magazine:



This is a page from a 2015 PS Magazine, I thought it would be interesting.



I always ran my AR's wet and I recommend the practice. You know there was a time when the US Army discouraged lubrication, I had a number of Vietnam Vets tell me that they were instructed to run their weapons dry. I believe that came from the Korea experience where lubes froze at -40 F.

I remember reading one web page written by one of those survivalist type instructors, the type of guy who shoots thousands of rounds a week, and sees tens of thousands being fired. He was absolutely scathing about the advice to run an AR dry. He kept his ar15 wet, very wet.

The "traditional" AR15 uses a direct impingement gas system that blows hot propellant residue right into the mechanism. I am not a fan of the system, incidentally. But given what it is, hot propellant does is accumulate all over the bolt carrier and locking lugs. Oils, and to a lesser extent greases dissolve that powder residue, preventing it from gumming up the mechanism. Greases are a combination of oil and a thickener. The oil performs the function of lubrication. These lubricants will keep propellant residue in suspension until the ability of the lubricant to dissolve propellant residue is exceeded, or the lubricant itself gums up. Motor oils are great stuff, have detergents that will dissolve gunpowder residue. A wet mechanism is very easy to wipe out, as most of the residue will be in the oil.

Of course if you are in desert sands, you have a problem. I have sand from the Giza plateau, a bud brought it back, and the stuff is like a talc. Extremely fine stuff, totally unlike anything I have seen CONUS. That stuff is going to be a real problem with any mechanism, wet or dry.

 

[LoonWulf]

OK, it definitely sounds like I'm shooting too many rounds before pausing. What did you mean by "with a saturated eat"? And, what oil are you using? I know, THAT is a whole different discussion in itself.

Thanks,
DD

I'm not even sure what I wrote that Google decided should say eat....saturated eat.....interesting.... saturated rag, I use clp, slip2k, and Lucas gun oils.....but mostly clp.

 

[someguy2800]

I personally don’t like to get them any hotter than being able to keep my hand on them for more than a second or so. It will depend greatly on the caliber and barrel weight how much shooting it takes to get to that point. I have no justification for this other than that it makes me feel better.

 

[labnoti]

There are two issues at question here: lube and heat. The lube issue has been addressed. Don't shoot them dry. Use an appropriate lube.

As for heat, a light profile AR barrel should take at least 300 to 400 rounds sustained fire. The idea of letting it cool off for many minutes after only 10 rounds is nonsense. While I don't have any reason to rip through ten 30-round magazines, there is no question that would not damage a barrel any more than firing 3 rounds a day for 100 days. The damage done to a barrel is in the thin heat-affected zone (HAZ) at flame temperatures well over 3300 degrees. A barrel hot enough to burn your skin or boil water at a couple hundred degrees doesn't add anything meaningful to that nor does cooling it 100 degrees. Again, I'm not saying you should burn ammo senselessly, but that if you think your barrel is getting hot, letting it cool off for a year doesn't stop the next shot from being a 3300+ deg. blow torch.

 

[bearcreek]

So I'm curious about the M16 or M4 - Are they a heavier duty version of the civilian AR-15 (besides being selective fire)? I can't imagine a cease-fire in a firefight to allow everyone's barrels to cool!

That depends on which "civilian AR15" you're comparing it to. They're not all created equal. Some are better than "mil-spec", some are lots worse. You'd have a tough time getting a good quality AR barrel hot enough to damage it using 10 rd. mags. Have to get real good at fast mag changes and have a pile of them.

 

[Demi-human]

On this I will agree with Labnoti.
A barrel that instantly blisters skin is still a long way from heat damage.

Human skin is a poor indicator of heat. Steel can handle heat to a few hundred degrees without detriment.
Fifteen degrees above mean body temperature is too hot for me.
My rifle could care less.
Verily, leaving a rifle in the sun for too long is too hot for my hands to hold the barrel...

Many humans take defensive carbine classes with grueling courses of fire that require gloved hands to use the hot weapon.
They keep making hits.
And keep on trucking, their weapons do.

Rest assured, your barrel will wear out only if you use it. It's a round count thing.

And Welcome aboard, @DownrangeDuck!

The High Road. A Clean Well Lighted Establishment!

 

[Demi-human]

All machines need lube.
Put enough on to keep it working, without wearing it yourself.
No one looks cool with black speckles all over their face after shooting once.

What kind to use isn't as important as using something.
But Slamfire's poster is an excellent rundown.

Yesterday I used motor oil off my truck dipstick to cool the drill bit I was using to cut out a screw in a threshold I was repairing. I didn't have any cutting fluid...

 

[Skylerbone]

@DownrangeDuck, if you are concerned about any given post you’ve over thought it. Mine was meant more for procedure when shooting for accuracy rather than any sort of expert advice. Your barrel will have many thousands of rounds through it before accuracy begins to diminish noticeably and despite money spent on a nice barrel it will always be a consumable part if used as intended.

From your description I cannot fathom any damage being done to this point; again, what I described is how I shoot for groups. The most important thing you can do is enjoy shooting it, thus relaxing a bit. Rest assured that worrying about such matters in times of peace will do more damage to you than the rifle.