XM 177E1 Dedicated Build
Dedicated 22 M4gery
I like them. Many, many years ago before ARs became mainstream, I took an EMF/Armi Jager AP-74 and added the collapsible buttstock, machined the barrel, then added a slip-over flashhider to mimic the XM 177E1 look. Was a pretty cool head turner at the range(s) way back when.
. 1960s Colt SP1/604 Dedicated 22 Retro Build
. M16A2NM Dedicated 22 Build
Mine is a 604 series clone. Actually, it Was built with a surplus 604 upper, A1 barrel, Type D buttstock and A1 furniture and using a CMMG conversion kit. When the ejection port cover is closed and the magazine is closed, you can’t tell it apart from my 5.56mm 604 build. When I built it, I didn’t want the gas blowing back into the bolt from the gas tube so originally I was going to leave it off. However, that left the hand guard to twist since the front flange is held in place by the gas tube running through the hole. My solution was to grab an old gas tube out of the DRMO box, cut it down to a stub then instal it upside down in order to seal off the gas hole in the barrel entirely is it wasn’t needed and would keep fouling for-or blowing out over the top of the barrel under the hand guards. It’s actually been a pretty good bunny buster as well as a plonked and trainer for new shooters.
I want a .22 kit but I have heard two things:
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Best thing ever! You can live out your Vietnam War Fortunate Son fetish at your local indoor range
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You’ll mess up your barrel
Which is truth?
While I think a dedicated rimfire upper (with correct twist rate) is the way to go, .22lr ammunition is getting a lot cleaner these days if you choose wisely. Fodder like the new CCI “Clean 22” using polymer coated bullets is a godsend, particularly to those of us running cans. https://www.cci-ammunition.com/whatsnew/newproducts.aspx
FWIW, I’m not aware of anyone actually having their 5.56 barrel ruined by shooting rimfire in it? I’d tend to think a round or two of full power centerfire after rimfire would pretty much clear it out, but I could always be wrong.
My next build will be an M16A4 dedicated 22 build but I need some help . I have the m16A4 Engraved Lower , the MAtech rear buis , but will need a KAC M5 Front RAS HG set up with panels , could any of you guys give me a few links to web vendors who offer take off ones for sale ? ( As it is the one proprietary piece that I need to make a nice clone of a USGI M16A4 ) thanx in advance for any assistance
Interesting.
I have an M16A1 upper 1/12 that I would like to enjoy more without having to drive, fund a buddy, blah when I got an indoor range I could be shooting .22 out of with less hassle.
Seriously looking at it
My original 1972 (Colt/Kaiser 603 upper with 1/12 SAK barrel ) shoots well with my spare CMMG SS 22 Conversion unit . I have not tried my USGI M261 22 Conversion unit and my 10 round inserts for it or in any of my centerfire AR platform weapons . But I will eventually get it out to the range as I have had some CLE (Compass Lake Engineering ) upgrades and spares for it .
In a CL barrel the conversion unit won’t damage the chamber unless you throw sand in, then pound the conversion in.
I have seen a blocked gas port. It’s not damage, it can be fixed, but it did make me recommend against heavy .22 conversion use in a rifle that may be a go to. This particular upper came off a registered lower and I would say it was run very hard with the .22 conversion.
okay…I solely want this for my M16A1 upper. I can’t always get to a range to fun full power ammo through these days.
It’s cringey but would a shot of compressed air through the gas tube clear any errant leading out for brushing/mopping?
I want to shoot my retro AR and figure this plus copper coated CCI stingers may equal good times without having to buy an umarex airsoft grade .22 to clutter up my safe.
I like my Ruger 10/22 sure enough but I want more time behind my Vietnam War build.
Also where can I get .22 conversion mags that look like 20 round straight bodies? Capacity is irrelevant
It looks like BDM stopped making the Xform mags. Might need to search out some used ones, they were made in the size of 20 round straight and 30 round curved.
This one with the gas port, it had a lot of FA use. I’d just make sure to shoot a mag or two of 5.56 every time you do get to a real range. I wouldn’t worry unless you start burning through .22 bulk packs.
Nah just casual plinking with a few months gap to regular range. I’d only use stingers.
Has anyone ever blown air through a tube? I don’t know if it would even help. It would get a mopping regardless.
Cmmg only sells the curved. I just want the aesthetic plus I like to sit and bench. I’m just trying to relax mostly
Thanks for your input and info.
I just want to revisit my A1 build I am less leery now.
I have 6 of the CMMG 10 rounders in the traditional 20 round Straight body gray plastic bodies from 2010- 2014 timeframe ( no longer made) and 6 of the BDM gen1 10 rounders in a black plastic 20 round straight body too . These all work in my Dedicated 22 Retros ( But 5 of the CMMG have been converted for usage with the CMMG Bolt Hold open Actuater that allows usage of Bolt catch like Centerfire configuration but with Rimfire . 
top Rifle has the CMMG BHOA and moded CMMG mag for usage with the CMMG SS 22 Conversion unit
A company called Jaeger (if memory serves me correctly) made a .22LR and .22 Magnum M16A1 look-alike. I recall seeing them decades ago in Shotgun News. I’d LOVE to have the .22 Mag model.
I use an old Atchisson .22 conversion unit in my 1 in 12 inch twist AR shorty. It is pretty accurate and reliable in my BFI RR lower on FA. I generally shoot 300 + .22 rounds during a shooting session out of it (generally cheap bulk .22) and always finish out the session firing a round or two of 556. It has never caused a problem. The only reason I would go to a dedicated barrel is for accuracy, but with how I am shooting accuracy is not that important to me.
I would think any PSI compressed air you could hold in the tube isn’t likely to blow out anything that got packed in by the .22LR PSI.
The few rounds of 5.56 after rimfire has been the gas system cleaning I have always heard of.
I would also think cleaning with Ballistol would be a decent preventive maintenance since it legitimately does dissolve copper, lead, and powder fouling. May be slower dissolve than some other dedicated cleaners, but no concerns about long term soaking dissolving rifle parts either.
Just picked up an original MAC/Atichisson (circa 1972 ) conversion unit & original magazine at Funshow here in Redding . Look forward to trying it out (Love the Magazine BTW ) and they are really more of a collector item (Even compared to an m261 or Airforce unit ) . (Only problem with mine is Original Cork material buffer in it has deteriorated and I’m gonna redo my own cork version and restore it to original .)