NAA Black Widow 22 mag double discharge

[M88]

I just purchased a NAA Black Widow model NAA-BWM, 22 mag to add to my collection. Thought it might be a fun little gun to plink with at the range, or possibly a nice little backup to my EDC. Included in the box was a notice telling me not to use Armscor Precision or PMC ammo, both Magnum or LR, for fear of double-discharge. I'm a retired electronics guy, not a machinist, but I do understand the basics of how a revolver works. Thus, I can't see how this could happen. The hammer comes down on the outside edge of that rim and it goes bang! How could that also fire another round in another chamber? With my Pietta black powder cap and ball revolver sure... several ways the flash from one chamber could reach the powder in another one if not loaded correctly. However, fail to see how this could happen in a modern revolver regardless of what brand round. Can somebody with more knowledge about this enlighten me please?

[Targa]

Great question, I have no idea but am curious as to others thoughts. Congrats on the gun by the way, that’s a little beaut.

[Bob Wright]

Double discharges can occur in revolvers by the loaded rounds slamming back against the recoil shield. This usually happens with centerfire cartridges in which the primer has not been seated correctly. This, though, is an extremely rare happening, and almost needs to be set up intentionally.

Bob Wright

[M88]

Thanks Bob, now it is starting to make sense. Of course a 22 mag is rimfire, so no primer. So are you maybe saying with those two brands mentioned by NAA, that rim is more sensitive, and thus prone to firing upon being "slammed" into the recoil shield by this little gun? I just checked, and there is about the same amount of cylinder fore and aft play as my other revolvers, my SP101 for example, BUT on all my other revolvers there seems to be more space between the rear of the cylinder and the frame of the gun. On my NAA, the back of that little cylinder is right up against the frame when pushed back. Am I on the right track here?

[Armybrat]

What damage did it do to your Black Widow?

I'll bet the members at the NAA forum would be interested in your experience:

http://naaminis.com/smf/index.php

[jaguarxk120]

If loaded rounds slam into the recoil shield there is a problem with that
revolver. Too much headspace.

[ds-10-speed]

It may be that the ammo they are referring to has bad brass at the rim. I have seen rims blow out (not Armscor but Remington), probably from a hairline crack at the rim. I was running the timer for a friend shooting a S&W 617 at a pin shoot last winter and had powder blow in my face, the rim split. I would guess if you had two of these flaws side by side that they would both go off. The rims are very close to each other in a NAA mini. Also I think if one did spit in a mini it would be like a hot blow torch on the adjacent rim.

[Aguila Blanca]

I've fired a LOT of Armscor rimfire ammunition, both .22LR and .22 Magnum. Never had a problem with it (although I don't own a NAA pocket revolver), and I consider it to be good ammunition. Personally, if I found a gun whose maker tells me that the ammo I have bricks and bricks of is unsafe, I'd take that as a commentary on the firearm rather than the ammo, and I would sell the gun as quickly as possible.

[M88]

Thanks guys. Just to recap however, I just bought this little NAA, and have yet to first clean it and then fire it for the first time. I've not encountered a double fire YET. Inside the box with the owners manual etc was a little note from NAA warning me not to use Armscor Precision or PMC ammo because of POSSIBLE double fire situation. Wanted to know how that was even possible in a revolver, and thanks to the folks here, I've been educated. Unfortunately, when I picked up the gun I DID happen to buy a box of Armscor along with some Gold Dot defense ammo. I am not going to use it, and will just donate it to my range. I agree with Aquila, I've shot tons of Armscor in other guns with no problems, my 30 Carbine LOVES it... and tend to think this is a unique NAA issue rather than the ammo. As I said, quick and dirty checking does show that the headspace on this little gun is less than all my other wheelguns. Maybe that's the issue... dunno. Other than this, have heard so many good things about this little gun that I had to have one and can't wait to shoot it.

[Carmady]

Why not call NAA and ask them what the deal is? They should know why they said that better than anyone else.

[T. O'Heir]

"...22 Mag is rimfire, so no primer..." Primer is in the rim. Hence the name, 'Rimfire'. No primer means no BANG.
What there is 'no' of is using .22 LR in a Magnum firearm. Different bullet diameter(.Mag's is 224 vs .223 for the LR) and all case dimensions are different. Rim thickness(Mag is .050" vs .043") and diameter(.294" vs .278"), case body diameter(.242" vs .226") are all different.
I'd be very surprised if the recoil would cause the case to come back fast enough to set off the priming with any ammo. Might if you tried to shoot .22 LR in a Magnum though.

[M88]

Thanks for the clarification T. O'Heir... yes of course a rimfire does indeed have a primer, in the rim. I'm aware of the danger of putting a .22LR in that magnum cylinder. That's why NAA makes a separate LR cylinder for the gun due to the the slightly larger dia and much longer length of the .22WMR. What gets me is that it's still OK to fire the LR through that barrel once you have the right cylinder? I thought the bullet dia was also a little bigger on the WMR than the LR. Wouldn't it "rattle" down that barrel a bit?

[M88]

OK... took Carmady's advice and simply called NAA and asked them about this. As I've found with many gun manufacturers, was able to speak with a very knowledgeable tech. First of all, this all apparently started more than 20 years ago, and he admitted that to this day they still don't know EXACTLY why this happens with Armscor or PMC ammo. After extensive testing, they theorized that because their cylinder was so small, and thus the rim of the rounds were so close together, the "aftershock" as he called it was enough to set off the primer in the rim of the adjacent round. However, they found that this happened very rarely, and apparently only happened with ammo made in the Philippines. They suspected that the Armscor primer in the rim of their .22 cal rounds was more sensitive than other manufacturers. He said over the years NAA has talked to those manufacturers about this but was still unable to come to conclusive conclusions. So has nothing to do with head space or adjacent rounds "slapping" back into the frame, they think it has to do with design of their gun when used with rounds that have more sensitive primer material in the rim. I guess the good news is they admitted that their design may have exacerbated this. The other good news is that it's apparently very rare. The fact that this all started over 20 years ago, given how many of these little guns are out there and probably many shooting Philippine ammo all those years, but you don't hear about this problem, says a lot. Thanks again for all those chiming in on this. I personally now feel better about shooting this little gun with that little cylinder being so close to my fingers and hand.

[Aguila Blanca]

As far as I know, all Armscor ammunition now being sold in the U.S. is manufactured in the U.S. That wasn't the case 20 years ago.

[M88]

Thanks Aquila... that makes me feel even better about this nonsense. I'm probably fine shooting this box of Armscor I just got. Whats the worst case scenario... got 10 fingers, do I REALLY need them ALL?? :-)

[indie_rocker]

I thought Armscor just started making ammo. Like in the last few years. Maybe it just wasn't commonly available here before the U.S. operation started making it. But I don't recall seeing it for sale or advertised until recently.

[ThomasT]

Armscor USA is made in the USA. Armscor Precision is made in the Philipines.

Funny they didn't include Fiocchi 22 mags because Armscor used to make their ammo for them as well.