There are few things I like more than firearms, and one thing I LOVE to do is strip my firearms down to pieces and reassemble it. It's a cross between the love I have for firearms, a love to know how things work, a love to make things work better, and just damn curiosity. So it is no surprise that the second I get home from the gun shop with my Sig Mosquito (it was on sale, I've wanted a Sig for a long time, and I love rimfires. I was (and still am) hoping the rumors are just that or that I can modify mine enough to make it function properly; kind of like how some have had to do with their P22s. So I am taking it apart, paying close attention to where things go, how they go, etc. When I finally get the metal frame from the Poylmer frame I had just a few steps left to go before it was all in pieces. I get it down to basically the hammer assembly and a single pin holding in a latch/lever of some kind (most likely a safety, or possibly part of the decocking mechanism). I figure the hammer is under tension of the hammer spring, so I'll get the pin first. As soon as I drift it out about 10% of the way, the whole thing comes apart in two, rocketing my hammer spring and bushings across the room (I found them, no worries). The ENTIRE frame is two freaking pieces of metal. Not a solid frame, but two pieces of metal. Now I don't own many handguns, but I find this unaccetable. The only thing that is stopping the recoiling slide and exploding shell from shooting out the rear and hitting me is a metal frame that is held together by two, count them TWO, metal nipples that are .095" in diameter and .065" deep?! Holy hell, I'm not even sure I want to trust this thing as a paperweight, let alone as a handgun.
Please tell me I am being absurd or unreasonable, because I have serious doubts about the safety of this thing now. Sure many people have fired them with no problems, but what happens if you got a spot of bad metal, machining, heat treating, etc. on that spot or if you run across a weak rimmed rimfire (ever since the .17HM2 this has been happing more and more) or both at the same time? Sure a .22 isn't that strong, but will .01235 cubic inches of metal really be able to stop it reliably ALL the time?
I'll try and get some good pictures of the nipples. I'm having a hard time getting them to come out, but when I get some good ones, I'll post them.
ETA:
As you can see in this picture, the nipples are very small. This is the nipple on the rear bottom of the magazine well, near where the hammer spring rests. The other is forward of the trigger pin. If you look closely in the original picture you can see them. I know it looks kind of like there are nipples on both side of the frame, but there is only one nipple and one detent where the nipples rests.