Yep, my old 971 busted a firing pin, too. I sent it back to Interarms, importer at the time, and it broke on the very first range sesson. I took it to a trusted gunsmith and he fixed it for cheap and it fired several thousand trouble free rounds before I traded it off on a Ruger .45 Blackhawk. The smith just said it needed proper fitting. I guess there was a frame burr in there or something stressing it, not sure, but he fixed it right for not that much money.
It does seem to be a problem over the years. I've not had the problem with my old M68. It is a better fitted gun than my early 90s M971 was. I really prefer the floating firing pin of my Taurus revolvers to a hammer mounted one. My Smith M10 has a hammer mounted one. It hasn't broken...knock on wood...though the forcing cone split once and put it out of commission. I had the same smith put a 4" heavy barrel I'd bought for 50 bucks out of a Shotgun News add on it. That one's been good ever since. I do clean the forcing cone of excess lead religiously now. I think tha was the cause of THAT problem. I just hope the firing pin holds up. I don't carry it for defense, though, just a range shooter.
Do NOT dry fire a hammer mounted firing pin without snap caps, hard on it. That might have caused MY problem as I was guilty of some dry firing with that gun. The smith that fixed it didn't seem to thing that was the problem, don't know. But, when I got it back from Interarms, I hadn't pulled the trigger on it and it busted on the first cylinder full. :rolleyes" So, I don't know. It worked after my smith fixed it, so I guess that's what matters. I didn't carry that gun for defense, but I did hike with it and killed a javelina with it once. Mine was quite light on the hip and pretty accurate. Took quite a few rabbits with it for camp meat, too, using wadcutters. I liked it as an outdoor gun, but my 4" Taurus 66 is a more accurate gun and slicker action and has the Ruger style transfer bar lockwork that I like. It fills that niche a bit better and it's almost as light on the hip to carry, being of K frame size.
BTW, I had a 4" barrel on my 971, not ported, and loved it. It was full lugged, balanced well, and felt recoil and control with heavy loads was NOT an issue. It was much easier on the hand and much less muzzle flip than my old Ruger Security Six. I can't seen porting a 971, don't like ported guns, anyway.
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