Had an Out of Battery happen in my A2 Armament conversion today. A first for me!  It damaged my BD magazine. After looking it over still shoots great.  Anyone have this happen to them on a AR22 conversion? Trying to post picture, can't figure that out - LOL




Figured it out I think

Years ago I had truncated cone shaped projectile .22LR ammo fire out of battery (OOB) when used in an Uzi .22LR conversion and when used in a CMMG .22LR conversion.  Those experiences led me to refrain from the use of truncated cone shaped projectile .22LR ammo in any type of firearm except bolt action.

MHO, YMMV, etc.

ETA: When the Uzi .22LR conversion had the OOB event, the ($15) extractor was knocked off the firing pin/extractor block and lost in the grass.

I had this happen a few times in my spikes 22lr conversion no damage was done.

I have had OOB with 22 rimfire.  I had a DPMS Gen 1 upper with no last round bolt hold open with ten round mags.  Repeated firing pin strikes wore the end of the rimfire barrel and was hard on firing pins.  I had an OOB because of the peened barrel which blew out the extractor spring and detents.  I also had OOB on my AKT-98 which was a common problem with that 22 rimfire.   I have no experience with 2A 22 conversion but OOB can happen with about any semi auto 22 LR.  The design dictates if there is any damage.

I had an OOB experience with a 2A Armament Conversion.  I can't recall if it damaged my BDM or not.  I don't think so.  It made my ears ring and resulted in a slug stuck in the barrel.  I've had my ups and downs with this 2A upper.  I want to like it because it's so cool but it has given me fits.  I buzzed the chamber with a dremel polishing drum and some polish.  I haven't really given it a workout since I've done that though so I can't say if it changed anything.  I think the bentz chamber they use is pretty finicky and you have to keep it clean.  I'd say 150 rnds you should be cleaning it with a bore snake or something to get any gunk out of the chamber so the round goes fully into chamber.

Yes I agree on reliability. Do you lube the bolt group or no lube per their instructions. Shot 150 rounds yesterday with CCI Standard and had one FTF.  The action seemed very slow and hard to cock after the 150 due to crud on guide rod. Like the accuracy not the cleaning. They suggest cleaning after 500 rounds. I may give it a try to see if it makes 500 but I am skeptical.

FWIW, IIRC back in 2010 when I bought my first CMMG (stainless steel) AR .22LR conversion kit (which I still use), the ammo CMMG (and J.A. Ciener) used for their live fire test of each and every assembly that they sold was Federal 36 gr., copper coated, round nose.  No claims as to suitability for use were presented for any other ammo.
As far as lube goes, the only lube that I use on the .22 conversions and dedicated assemblies that I have is a drop of oil at the extractor pivot pin.

Disclaimer:  I have no affiliation with or financial interest in any vendor or manufacturer; and I am not a competitive shooter or a blogger who receives any form of compensation for endorsements or favorable public or private comments.  Use of vendor and/or product brand names, if any, is for informational purposes only.

Best of luck.
MHO, YMMV, etc.  Be well.

The first upper receiver I put the 2A bolt in was a DPMS extruded heavy-walled upper.  It was very tight and seemed to drag on the bolt as you describe.  I switched it over to a standard mil-spec forged upper....of unknow origin.  It fit much better and cycled easier.  I still noticed some gouging above the ejection port where the screw in the bolt that retains the extractor was was making contact with the alum of the receiver.  I smoothed all that out and I do use a dry lube on the assembly.  On this particular upper receiver, I took the receiver truing tool from Midway and actually put some lapping compound around the outside of it and lapped the inside of the receiver.  I'm not sure if this helped or not but the bolt does travel pretty freely.

You'll find this interesting...I actually used a CMMG manufactured barrel with the 2A bolt.  I had to remove the locating pin atop the CMMG barrel and turn it slightly so it would line up with the 2A bolt but this combo actually ran like a sewing machine.  This indicated to me that the problems I was experiencing were more likely due to the chamber on the 2A barrel being pretty tight for a semi-auto.  They said they used the Bentz chamber and that's why they recommend the ammo they do but I found it to be pretty finnicky even with that ammo.  I took a dremel cone and filed it down to fit inside the chamber with some polishing compound.  I have not had a failure since I've done this but I haven't run more than about 50 rnds at a time when I've had it out.  I'll have to take it out again and see how far I get without any failures.

Intentionally trying to induce a malfunction by not lubricating a mechanical device seems counter-intuitive to me.

I've shot many thousands of rounds through the aforementioned .22 conversion over the last 11+ years without any sign of wear whatsoever. I also have two dedicated, 2018 and 2019 vintage CMMG stainless steel uppers each of which that I have shot several thousand rounds through without any sign of wear.  If one examines the bolt/recoil and frame mechanism, one notes that the only place where there is force between moving components is the extractor on its pivot pin.  Everything else is essentially free floating without any appreciable normal force vectors causing friction and the concomitant wear.
Slathering oil on all the parts provides a base for contamination to gather and may actually cause wear and/or malfunctions due to the accumulated contamination.
And to be clear, this is .22 ammo in a stainless steel assembly under discussion - far less pressure and potential friction than centerfire cartridge applications (where I do use lube on potential wear surfaces).
MHO, YMMV, etc.  Be well.

Yes adding a bunch of liquid lube to any .22 is just asking for a instant mess of slurry and sludge build up..And OOB discharges and malfunctions..I only use dry lube occasionally with maybe a very tiny drop on the extractor..I have used the dry lube method in all my .22s for a very long time now and dry lube has always worked..And no excessive wear has ever been seem over that long period..

Some guys go as far as that must not have been enough oil yet if something malfunctions, and figure it must be a quart low yet,,LOL

I only run CMMG .22 products, have never ever had a OOB Discharge, and cannot even recall any specific malfunction at all in thousands of rounds using dry lube..

I have had a few CMMG Firing pins break..But that is nothing to do with lube..I have a bore buddy pin I have been running for over two years and no breakage as of yet..

I agree with all the lub comments.  I do not lube the A2 setup as per their instructions. The issue seems to come from the crud build up on the guide rod starting from the back of the barrel face. After about 50 rounds the action slows, and the crud seems to affect the bolt completing going into battery.  In steel challenge I need to run 150 to 200 rounds without issue. My CMMG/RTBA systems have no problems and have not had an OBD with them.  I also have a Velocity Firearms barrel with their collar on a CMMG bolt assembly that functions 99%. I like the feel of the AR22 over a 10/22 for steel

After shooting ten or twenty thousands of rounds of rimfire through my kits, mostly in full auto - I've lost track of the OOB kabooms I've had. Lots of them. Just pry it out of there and keep on shooting every time.  Nothing is ever damaged.

The gun was not damaged, but it did blow the bottom cover and separated my BD magazine at the bottom - taped it back together -LOL

ditto

I had one destroy a BDM 15-round magazine.

Is it a trend for the BDM mags to get damaged?  I've never had a mag damaged but then most of my shooting was with converted metal Bingham mags from Ciener, the original 30rd mags.

Years ago I had 4 out of battery discharges in my CMMG dedicated bbl with Ciener kit.  All four of those were with Remington ammo.  I blame the ammo since I've had other out of battery discharges in other firearms using Remington ammo.  I've even had an out of battery in my MAC 10 9mm using Remington ammo and a squib load once.  I never shoot Remington ammo anymore.  Friends don't let friends shoot Remington ammo.

I've not seen one in an AR-22 (yet). Now the American 180 I had back in the '90s is a whole 'nother story. At least ejection was straight down, and one learned pretty quickly to keep one's left arm out of line with it.

To be somewhat pedantic, it is my understanding from what I've read, in 1993 Ciener bought all rights, title, interest, and tooling for the Atchisson MkII/III conversion and magazines from Max Atchisson.  But in 1994 the Clinton Assault Weapons and High Capacity Magazines Ban law was passed so Ciener couldn't make any new 30 round mags of the original Atchisson pattern (U.S. patent no. 4297800).  After Ciener's existing stock of Atchisson pattern 30 round mags sold out, Ciener converted pre-94 Bingham mags to work with the Atchisson pattern conversion because most conversion kit buyers didn't care for 10 rounds only mags.  The Atchisson conversion assembly and magazine patents both expired during the AW Ban, which itself expired in 2004.

MHO, YMMV, etc.  Be well.

Great recap.  I still use my metal Ceiner/Bingham mags cause they never wear out, never take damage from a kaboom.  They just don't look as cool as an CMMG/Black Dog mag/S&W mag, but I have enjoyed 30rd capacity since the 90's.  Ciener, being the mega a-hole that he is, bragged about having millions of dollars worth of Bingham mags to convert in his inventory and the only source for the 30rd mags.  At the time of the AWB, people were converting existing high capacity magazines to other guns such as Bingham to AR15 (add mag block), suomi drums to M11's, etc but then ATFE decided that was too cool and declared any mag had to be able to function in the original gun it was designed for and that shut down all the conversions and Ciener was stuck with a large inventory of mags that had yet to be converted so they were useless, until after the ban but at the time he was happily gouging people up to $249 per 30rd mag at the height of the ban.

Of course before all this happened there was Rick Kuehl of Kuehl Precision Firearms (KPF) who was producing match .22 rimfire barrels with feed ramps and extractor cuts.  He used the Atchisson kit but removed the chamber adaptor.  Essentially my kits ran like a dedicated CMMG but without a barrel collar as that stuff was built into the actual barrel.  When I removed my kit, nothing kept the bolt from trying to jump off the rails.  The uppers you see in my video being shot in full auto are KPF uppers (which got stolen at one point), but he quit production when CMMG entered the game.  Rick was afraid that someone else would make a conversion system that used 30rd mags and he didn't want to get stuck with a load of barrels he couldn't sell.  A shame, he had the best barrels and they used no collars, match accurate, and I still have a few of them including a 10", and one that looks like an M4 barrel with M203 cut.  Back then I was able to run full auto with his kits and the stock OEM auto sear trip and anti bounce weight in my M16.  I broke tons of firing pins (no good ones being made at the time), the weights would break as well cause they were soft metal, and maybe once a sear trip.  Nothing was chromed.

KPF uppers and converted Bingham mags on an M16


Considering all the kabooms I've had with these kits, I guess it's a good thing I ran those converted Bingham mags or I would have destroyed a lot of magazines.  I'm not really using them anymore, lately I'm using CMMG or Black Dog and the two kabooms I had these last few months did no damage, just pried them out with my Leatherman and kept banging like I've always done.  Last OOB almost completely shredded the back half of the case.