Anybody running with one of these .22 conversion kits?  OMB Express has them on sale for $120.  Cheaper than a new S&W MP15-22, but how accurate are they and how's the reliability?  Problems with fouling in the barrel?

I've had one for about 2 years.  Haven't had an issue yet.  I haven't noticed any fouling but I run full power 5.56 through after a couple 100 rounds.

don't have one, but plan on getting one eventually.

generally the drop in conversions seem to have mediocre accuracy due to the freebore of the chamber adapter and the twist rate that's faster than it needs to be, and the bolt hold open doesn't work,

which is why i went with one of the S&W 15-22s oh noes.. another rifle! the 15=22 mags also have a button on the side of the mag that makes 'em easy to load.

CMMG also has the stainless conversions if you want sighting that's easier to clean than their standard conversion.

I've had mine for about a year.  For plinking, it is the coolest thing ever invented.  Walmart's cheap .22 seems to work fine with my setup with no issues.  The bolt does lock back to the rear when it is empty but will go forward as soon as the magazine is removed which to me is not a major concern.  Always follow up with a few .223 rounds just to clear up the gas tube though.

no, it's not a major concern... but it' not the same manual of arms as a normal AR, so if you want he .22 conversion as an understudy for the regular rifle... it's slightly different.

if you just want it as a plinker, not a problem. if you want it as a training tool it's a difference to deal with.

I think they have a part coming out that fixes that(bolt lock):

http://cmmginc.secure-mall.com/item/.22-Conversion-Bolt-Hold-Open-Actuator-1525

I've not seen a date for general availability.

Keith

that would be interesting if it works reliably and is easy to swap in/out without tools when you swap the BCG.

I figured mine paid for itself the first day I had it out. They are fun little things, and give minute-of-soda-can accuracy, which is fine by me.

I have the CMMG stainless kit.  They are periodically on sale because I believe CMMG is coming out with a new model that will have more function, bolt hold open, forward assist, etc.

I paid $150 for the stainless model with 2 mags.  The SS model is supposed to run smoother out of the box with no break in and easier to clean.  The mags are a pain to load, the max capacity is 26 rounds vs 50 with my 10/22.

All that said, I think the kits are great.  I would rather buy a kit than a .22 AR rifle.

Black Dog Machine has 50rd drums for the conversions, as well as the 10/22 and 15-22

I've had great luck with my drop in .22 kit with the full auto trip, but it gets dirty fast. If you have the $ go for a dedicated .22lr upper they are more reliable.

I have one and love it.

As stated - the mags are a pain to load.

I had intermittent FTF with mine when I got. I found out the trouble was caused by my RRA 2-stage hammer. It has a razor sharp corner on the top that was snagging on the adapter. I file the adapter and it has worked 100% every since.

Recommended!

I also shoot a mag of .223 after use....

Your 1/7, 1/8, or 1/9 twist barrel will give you groups of 2-4" @ 25 yards with normal bulk ammo (38, 39, 40 grain).  I've found 60 grain ammo to be around 1" on a good day.  The first generation of CMMG kits had a known problem that the factory was fixing free of cost.  As I understand it, 2nd gen forward didn't have this issue.

If you're looking for close range plinking with your standard AR at a reduced ammo cost this is for you.

If you're looking for 10/22 or dedicated 22LR accuracy look elsewhere.

Edit: As far as reliability - I got two the the atch kits and 1 spikes.  They run well enough for a few hundred rounds (300-500) then start to have 1-2 failures per 25 rounds.

The 22LR dedicated upper I have runs a little better for longer, but 22LR is dirty.

Yeah, totally get one.

When they work they're awesome. But sometimes there are some QC issues that slipped through.

Mine required a little polish in the chamber, which I did with a dremel and a polishing stone. What was once a jammomatic turned into a bumpfire champion.

Travatron got one and had nothing with problems with it. We ended up doing a bunch of tech-work on it, trying to figure out the problem, I think we concluded that the problem was in the return spring, since his kit worked fine with my return spring and mine had all the same hiccuppy jamming problems using his spring.

On the other hand, Buffetdestroyer's kit as I recall never had any problems whatsoever.