Potential for pencil barrel overheating from 22LR?

[max68w]

BCM Lightweight (Not BFH or ELW) 16" Midlength Upper with .625 at FSB.

I am using this upper in conjunction with a CMMG Conversion Kit to build an AR primarily for use as a dedicated 22LR rifle for cheap training, plinking, and a BCG swap away from a backup patrol rifle.

Question: Given the profile of the barrel and the heat and pressures generated by a typical 22LR cartridge, do I have to worry about the barrel overheating in the same way I would if I were using .223/5.56 rounds? Can I mag dump 22LR through a pencil barrel just like I do with my Ruger 10/22 or my S&W 15-22 with carefree abandon?

Add'l Info: This is my first AR-15 ever, and I don't understand to what degree heat will affect a pencil barrel from either .223/5.56, much less 22LR. I'm hoping someone can give me a general idea of whether I should worry and how much about overheating a pencil barrel with 22LR rounds.

I GENUINELY appreciate any and all input as I am new to the world of ARs. Thank you.

[TKM]

They haven't made that much 22LR yet.

You can try one of these if you believe in empirical evidence.

https://www.youtube.com/watch?v=J50N5lQoAFw

[BajaJames83]

Beltfed?

[fmunk]

I don't think even Jerry Miculek could overheat a 22LR barrel. My god, the overthinking of late is just... mind blowing.

[max68w]

Thank you. A lot of YT videos on pencil barrels have me freaked out about pencil barrel potential for overheating. I appreciate the responses. I feel quite reassured now.

[max68w]

By the way, that video on the American 180 was awesome!

[ar15barrels]

BCM Lightweight (Not BFH or ELW) 16" Midlength Upper with .625 at FSB.

I am using this upper in conjunction with a CMMG Conversion Kit to build an AR primarily for use as a dedicated 22LR rifle for cheap training, plinking, and a BCG swap away from a backup patrol rifle.

Question: Given the profile of the barrel and the heat and pressures generated by a typical 22LR cartridge, do I have to worry about the barrel overheating in the same way I would if I were using .223/5.56 rounds?

22lr burns about 1/10 the powder of a 223/5.56 cartridge.
That means you would need to run about 10x as many cartrdidges through a barrel in the same amount of time to generate the same amount of heat.
It's unikely you could ever cause a heat problem with a 22LR unless you have a full auto with perhaps a 1000 round feeding system.

[17+1]

The bigger problem I see if you’re saying this is going to be a dedicated 22, but you’re using a conversion kit.

I’d say just get a dedicated 22 upper. CMMG and PSA make good uppers.

[-hanko]

If you cannot overheat a 10/22 barrel, an AR barrel shouldn't have an issue.

[Ki6vsm]

Thank you. A lot of YT videos on pencil barrels have me freaked out about pencil barrel potential for overheating. I appreciate the responses. I feel quite reassured now.

Consider that during the entire Vietnam War the M16s all had barrels of that same profile. People just called them barrels back then. No "pencil". And those rifles were all select-fire and run at full-auto on a regular basis. If overheating was a concern, I think Armalite would have gone a different way with the barrel profile.

[Jimi Jah]

My AR-22 pencil CMMG barrels get warm after a couple hundred rounds. About as warm as 5 rounds of 5.56.

[SVT-40]

Beltfed?

Maybe a .22 mini gun with a bazillion round magazine...

[m16]

[audiophil2]

I've had my barrel lead up on full auto. That is the only concern. And I have those 275 round drums. When I run 50 round drums of 22lr I run a mag of 223 after about 200 rounds. Keeps it clean of lead.

[maxicon]

The bigger problem I see if you’re saying this is going to be a dedicated 22, but you’re using a conversion kit.

I’d say just get a dedicated 22 upper. CMMG and PSA make good uppers.

Yes, the twist rate will be all wrong for .22 rimfire, and your accuracy will suffer.

My DPMS dedicated .22 upper has a 1-16 twist rate, compared to the typical 1-7 to 1-9 .223 twist rate.