Bore diameter

[Malacai Johnson]

OK, I'm starting to get to gether the things I'll need to rool my own BP loads for my new Uberti Henry. Does anyone know the bore diameter for the Uberti? Do they vary much? Am I gonna hafta slug my barrel to know what size bullet to get? Any info will be appreciated.

Thanks,

Mal

[Silver Creek Slim]

What caliber is the Henry?

Slim

[Malacai Johnson]

Sorry. It's a 45 Long Colt.

Mal

[Silver Creek Slim]

I would say .454", but I'm not sure.
I size all my .45 Colt boolits to .454", but .452" should work also 'cuz I know people that size their boolits to that and they work fine.

Slim

[Driftwood Johnson]

Industry standard groove diameter for 45 Colt has been .451 ever since the end of WWII. Around 1956 to be exact, when the first Second Generation Colts were made. Up until 1940, standard gorove diameter for 45 Colt was .454. In 1956 it was changed to .451 in order to match the groove diameter of 45ACP.

Of course rifles chambered in 45 Colt are an entirely modern concept, instigated largely by the success of Cowboy Action Shooting. But industry standard groove diameter for 45 Colt today is .451, regardless of the form of the gun. Of course, standards are one thing, and reality is another. Individual groove diameters can vary slighlty, due to tool wear in the manufacturing process. The only way to truly know your groove diameter is to slug your barrel.

Incidentally, while I have my schoolmarm hat on, the term is Groove Diameter, not Bore Diameter. Bore diameter is the diameter across the lands of the rifling. Bore diameter corresponds to the diameter the hole in the barrel was drilled, or 'bored' before the rifling was cut. Groove diameter is measured across the bottom of the grooves, and is the important measurement to consider when choosing a bullet diameter.

[Malacai Johnson]

Slim and Driftwood,

Thanks for the info, especially the groove-vs-bore diameter stuff. I probably knew that at one time, but my head gets more filled with stuff every day. Sometimes I wish I had more of an open mind so some of it could escape. I'll probably forget this info in a year of two, but I can't seem to shake the theme song from "Gilligan's Island"!

Mal