[steelbird]

I've been thinking about getting a cartridge conversion for my Pietta 58 Remmy - don't know what would be best for mine. It's an older one - from the date code, I believe it was made back in the late 70's. Not sure which one would work best, and if there is one, what ammo loads would be too powerful for it. I don't intend to put anything other than cowboy loads in it, but I know that some are stronger than others. Any suggestions?

[rcflint]

There is a difference in fit and finish between old and new Piettas, but no difference in strength. Both my converted Piettas work fine, and shoot smokeless without a problem.

[steelbird]

rcflint-

Thanks! What load(s) do you shoot with?

[rcflint]

I reload to "Cowboy" legal, which is, per SASS, less than 1000fps handgun and 1400fps rifle. My loads, lately using TrailBoss and RNFP lead bullets are around 800 fps handgun in the 44-40 and 45, and with the 44 Russian, probably more like 750 or a bit less.

Thr Remington "58" does not run smoothly on BP without squirting Moosemilk or such on the moving parts, and the higher gas velocity of the cartridge makes BP a quicker fouler in the Remington cylinder pin area. Actually, using a Drop-in cylinder like the R&D or drop-in Kirst helps, as removing the cylinder to load and unload tends to keep the cylinder centerbore and cylinder pin freer of Black Powder fouling, and is an opportunity to lube them.

Using smokeless is easier to keep clean while shooting, and the Remington steel frame is plenty strong enough to take smokeless, as the key component is the cylinder, and both R&D and Kirst are rated smokeless.

[Old Fuff]

Before investing in a cartridge cylinder check the barrel's groove diameter. Some cap & ball revolvers run as large as .460" and as tight as .446". Most bullets used in .45 Colt cartridges mike out at .451". It isn't so much a case of a mismatch between the bullet and bore diameters being dangerous (although this is remotely possible) as it is that accuracy may be disappointing, and excessive leading a problem.

[rcflint]

The Uberti groove diameter is .458, but I think the Pietta is closer to 451, as is the ROA.

[Old Fuff]

The Uberti groove diameter is .458, but I think the Pietta is closer to 451, as is the ROA.

The Ruger Old Army was always pretty consistant at .451", but the Italian guns were more "flexable" over the years, with the oldest ones being most so.

At the time conversions to metallic cartridges hadn't been taken into consideration. Also over the years tooling generally improved. In any case slugging and measuring the bore diameter may save some expense and disappointment later. Given the circumstances I consider Italian guns of all makes to be a case-by-case matter.