Will firing .22lr damage a heavy barrel AR-15?

[hholman]

I'm considering getting a CMMG .22lr conversion kit for my heavy barrel AR-15. Would shooting .22lr through it damage the barrel or upper at all?

[zfields]

usually will just lead the barrel quite a bit. Shouldnt damage it though at all.

[Helpful_Cub]

No. You may have occasional issues cycling since a 22lr has less blow-back pressure than the .223, so it may be ammo picky. But the barrel and upper can handle far worse pressure extremes than the .22lr can generate.

[Merc1138]

Dirty, yes.
Damage, no.

[TKM]

I'm not sure if you could damage an AR upper by shooting it with a 22 LR.

Except for the dust cover and maybe the gas tube.

[2shotjoe]

no, but 22lr really needs 1/16 twist barrels.

[HK Dave]

The pressure 22lr creates vs 223 is miniscule. You'll be fine.

[Calif Mini]

22LR vs 223

I have heard that the gas system will get lead deposited and can actually restrict it some. Also a bear to clear out easily.

Wives tale or fact? That is my question.

[Merc1138]

I have heard that the gas system will get lead deposited and can actually restrict it some. Also a bear to clear out easily.

Wives tale or fact? That is my question.

I've heard of crap(powder residue, wax, etc.) getting in the gas system(and shoot a mag of 5.56 to clean it out), but not lead.

[Zippiot]

I've heard of crap(powder residue, wax, etc.) getting in the gas system(and shoot a mag of 5.56 to clean it out), but not lead.

And sand, that famous .22lr sand.....

But as stated above you would want 1:15ish twist for a .22lr

[CHS]

Damage? Absolutely not. I can't think of any scenario where .22lr could possibly damage an AR that's shooting it.

Now, there are some specific issues with .22lr that you should be aware of:

1.) It's dirty, and conversions/dedicated uppers are blowback so you'll get lots of crap in the upper and lower.
2.) Lead shavings and the above crap CAN clog the gas port after a while. After each brick's worth (aka 500 rounds) you should probably run a couple rounds of .223/5.56 through the gun and it will clean out the gas tube just fine.
3.) Conversion kits have crap accuracy. Period. You've got almost 2" of free-bore before the bullet hits rifling, a slightly oversized bore (.223 vs .22, yes they are different), and a VERY high twist rate compared to what's ideal for .22lr. Dedicated uppers fix #2 and #3, but are still dirty as hell just like any other .22lr.
4.) Your hammer really should be of the rounded variety for the best reliability. The 'stepped' hammers can cause really bad reliability issues.
5.) The factory springs can be too heavy to let .22lr cycle reliably. Swapping out to a lighter hammer spring can improve reliability and reduce FTF's/FTE's.

I have also found that liberal use of Slip2000 as a lubricant keeps .22lr AR systems functioning longer. It doesn't gunk up into sludge like most oil-based lubes do with the crap that .22lr pumps into it. With Slip2000 the dirt just slides away and the lube keeps on working.

[Seesm]

If the gas tube gets blocked up by firing too many .22 rounds there is a little trick to clear it out... If yiou need help let me know.

[Munny$hot]

I've shot thousands of 22LR without a single FTF or FTE with a CMMG Evolution drop in bolt. It's as accurate as a standard AR-15 at 25-50yards. The key is to use good ammo. I have found that Federal Bulk works best for the price. The only problem I did have is breaking a firing pin, but CMMG quickly replaced it without question. If your looking for the absolute best deal/price contact "Dave" shadow65 here on CalGuns.
Dave's dealer link: http://www.calguns.net/calgunforum/s...d.php?t=426135