It broke plinking at plastic bottles. I had a misfire, then the lever wouldn't close. At that point I put it in the truck and brought it home. Took it down today and the broken end fell out when I slid the bolt out.BTW: Dry firing breaks `39 firing pins.
(learned that the way as early as `59)
It says "manufacturer Marlin" but also says its a reproduction. I think I'll give that one a try... thanks for the link.https://www.gunpartscorp.com/gun-manufacturer/marlinglenfield/rifles-marlin/39-series-2/39
Numrich has the firing pin listed for $27 but doesn't say anything about fitting required. I bought a guide spring for a Sears-Roebuck .22 (Marlin model 881 equivalent) from this website and it fit in perfectly.
I just ordered one from Wisner's (leaving three in inventory-4/28/20) and found them very easy and pleasant to deal with. Before you order, though, you may want to call between 1:00 and 3:00pm, Pacific Time, when their technical expert is in. You'll want to make sure that the firing pin you're considering is the right one for the year of manufacture of your model 39.Plus one on Wisner's they have stepped up on out of production parts and I have always had good luck with them.