I just aquired a 1930's manuf. New service in 45 colt. How well are these models built. I do handload and would like to know if I can bump up the performance over what ammo is available from the factory and not worry about ruining it.
I understand that they are very stongly made for it's time period. However I don't think I'd try any +P ammunition in it. The steel is nearly eighty years old and metalurgy has come a long way since then. Just my two cents worth,
The New Service is a strong revolver and with careful attention to handloading procedures and by observantly working up loads one can obtain slightly better performance. It's easy to ladle in the powder to achieve more performance but, while the New Service will handle it, there is no point in seeing how far one can push the revolver towards the edge. Personally I've always considered a factory .45 Colt load to be pretty "high" performance. Other tricks to try are different bullet shapes or weights which could yield more effective loads without higher pressure. I'm a big fan of the semi-wadcutter bullet in the handgun. The old Lyman No. 454424 bullet mold throws big SWC's that weigh around 255 grains. At 800 fps they cut a nice large hole in things. Excuse me while I pontificate that I'd prefer such a .45 Colt load over any .357 Magnum offering, 125 grain hollowpoint or otherwise, when considering authoritative revolver rounds.
Why do you need to "bump up the performance?" Are you going to use it as a self-defense gun? Surely you have something newer for that purpose. While the NS will stand heavy loads because the cylinder walls on a .38 are so thick, why bother? I presume it is shot for pleasure only and standard loads should be fine for that purpose.
It is your gun and you can do as you please, but I would not "hot rod" the old girl even though it is a very strong gun.
One of the things that throws the old Colt action out of time is the battering the hand gets from recoil. Remember the hand is one of the parts holding the cylinder in lockup, when the recoil happens the weight of the cylinder is thrown against the tip of the hand. Heavier loads means more recoil, so your timing goes away faster.