My wife bought a 58 NMA in 76, she gave it to me maybe 10 years ago.
This last year I could not stand it anymore and got setup to shoot it. I had sworn off BP pistols back in about the same year as they said to put Crisco over the bullet and what an awful mess. Whatever I had bought I sold.
Ok, taking hers out I learned a lot shooting it. First the half cock timing was wrong. I don't think it had been messed with but she was shooting with a friend back then, the screws were not marred and extremly tight. I did not even know what the half cock was supposed to do. The arms of the Bolt or the pin was wrong.
Other than that it is a nice gun. Action is slick, kind of S&W modern revolver like. Decent quality in my opinion and I don't see anything off putting and in fact it was nice enough action that I got lured in.
I then bought a 58 NMA Pietta, got a spare parts set for it. Looked at the bolt for fix of the ASP, it was wrong on the latch end. but I filed it down and got it to fit through the slot and amazing it worked, so I got half cock working nicely.
Now I was getting up to speed so this was all new to me. I latter found some decent pictures and the Uberti bolt looked identical to the ASP bolt, so I got one. It did not work at all. So I put the modified bolt back in and there she sits.
I have not found it to be all that accurate. Gave up and got hooked on a Ruger ROA and Uberti 47 Walker because I was having fun. Those are good enough at 25 yards I can get decent groups and the ASP was not. Cylinder reaming may help, different powders but I did try various 777 and Pyro P loads.
I don't know if that is typical, not many out there or reported here. I have RS powder now and GOEX so maybe should try those one of these days.
The cylinder are tapered, so they don't shave lead but they seal a .454 ball well, did not try a .451, getting into iffy chain fire. No idea if reaming cylinders would help.
