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 Factory 22cal Rifles are they eaisly converted to 5.56
monkeythumbs  [Member]
1/19/2010 4:00:42 AM
I had a co-worker come up and ask me if the factory 22 rifles such as the M&P 22 amd colt/uruamax M4 were able to be changed over to 5.56. I've never owned one of these newer 22 and was wondering if anybody could offer insight. I've heard that the colt lowers were plastic so I'm assuming that would be a NO-GO, no idea about the S&W though. I told him just build a 5.56 rifle and get a conversion kit. He had heard about a 22 AR rifle for $400 and go all excited and about getting into AR's on the cheap. I told him he could build a.5.56 rifle for a little under $500 if he didn't mind a used upper, just over $550 if he wanted new, and then buy a conversion kit if he wanted to shoot 22. Can anybody comment on the factory 22 rifles , or set me straight?
goodoleboy  [Member]
1/19/2010 4:18:38 AM
Ive heard the conversion for the ar15 are not as accurate due to the twist rate & mm differences in bullet size also..
Scorch05  [Team Member]
1/19/2010 4:35:18 AM
Originally Posted By goodoleboy:
Ive heard the conversion for the ar15 are not as accurate due to the twist rate & mm differences in bullet size also..


Conversely a converted dedicated 22LR AR will not be accurate at all. Today's standard twist ratio for AR bbls are 1/9" or 1/7" twist while dedicated 22LR bbls are 1/16".

My 22 conversion kit will shoot about a 4-5" 20 round group off hand w/ irons at 25 yards with Federal bulk ammo and a 1/7 twist bbl. The groups tighten up some with better ammo and off a bench. The groups aren't awesome, but I doubt you will get that kind of grouping shooting .223 out of a 1/16" bbl unless the bullets are 40gr or less.

The only way you could shoot .223s out of a dedicated 22LR upper any how would be if the 22LR chamber was removable. My opinion, get a dedicated 22LR AR if you want an accurate 22 AR. Or get a .223 chambered AR if you want to blast 22LR because it's cheap. If this case you can't really "get both".
bada61265  [Member]
1/19/2010 7:21:51 AM
simple answer to the op`s question, no both of these are designed as 22`s and would be comparable to trying to convert a ruger 10 22 to shoot 223.
Chuck  [Team Member]
1/19/2010 7:23:25 AM
A new upper receiver is the only way to "convert" any of the .22LR AR15 types to 5.56mm. This is the same way a 5.56mm model is converted to .22LR other than a device like the Ciener and similar that replaces the bolt group and has a chamber insert.

Specifically neither the Colt-Umarex nor the S&W M&P15-22 can be converted to 5.56mm.

The Colt is a totally proprietary design that only resembles the M16 externally. For example you have to unscrew the compensator to take the rifle apart. The MP15-22 is much closer but will not accept the upper receiver of the M16.

–– Chuck
frog5215  [Member]
1/19/2010 8:40:33 AM
Milspec 5.56 uppers won't go on the Colt or S&W .22 lowers. Pin spacing is deliberately different.
Buffer "tubes" are molded as part of the lower and in any case are solid; there is no way to put a buffer or spring in, and nowhere for the 5.56 BCG to recoil into.
It costs about as much to build a .22 milspec AR as to build a 5.56, unless you use a Chiappa .22 upper, which is so new it's unclear whether it's any account.
Basically, you get what you pay for.

Uh, Scorch? Goodolboy? Ever heard of a dedicated .22 upper?
That's really what's under discussion here.
I have at least one dedicated upper that will shoot with ANY 5.56 upper to the range limits of the cartridge.
monkeythumbs  [Member]
1/19/2010 3:09:12 PM
Thanks for the replies, I was curious about the factory 22AR's and you guys answered my questions. I'll tell him what was written here and it was pretty much what I thought too. Didn't know about the buffer tube, and pin locations. Thanks again.
27Beck  [Member]
1/19/2010 8:35:21 PM
Originally Posted By monkeythumbs:
. He had heard about a 22 AR rifle for $400 and go all excited and about getting into AR's on the cheap.


He might have heard of the S&W 15-22 or the Sig 522. Both of these guns have been purchased for around $400.00 each. Both are decent shooters.
frog5215  [Member]
1/19/2010 10:42:36 PM
Originally Posted By 27Beck:
Originally Posted By monkeythumbs:
. He had heard about a 22 AR rifle for $400 and go all excited and about getting into AR's on the cheap.


He might have heard of the S&W 15-22 or the Sig 522. Both of these guns have been purchased for around $400.00 each. Both are decent shooters.


OP SAYS in his Original Post that his friend asked about the S&W M&P 15-22 and Colt/Umarex, so I suspect he was asking about the S&W M&P 15-22 and Colt/Umarex.
rlandry6  [Member]
1/21/2010 6:45:32 PM
I just ordered the dedicated .22 upper from tac sol. For another $50, I don't have to deal with compatibility issues and it's guarranteed. iIf it's not right, tac sol makes it good. Hard to beat that. There'a just no reason to go on the cheap only to have to put up with a piece of equipment Ithat sucks.