does anyone know if 45. long colts cam be safely fired out of a marlin 45-70 gov.
i undderstand that it can be done out of a 45 casul.
and if it can, does it reduce barrrrrel life?
thanks in advance,
dog man
p.s sorry if this is a silly question

I don't have my reloading manuals in front of me to check rim/case dimensions, but even if it's close enough to shoot, I doubt you would be satisfied with the results. The .45 Colt bullet is typically .451- .452 dia., while the .45-70 is .458 - .459 diameter. The diameter difference, coupled with a tremendously long jump to the rifling, would probably lead to incredibly poor accuracy and terrible leading. Even in my .454 handgun and rifle I avoid using .45 Colts, due to reduced accuracy and chamber leading from the longer jump to the bore.

Good advice above. You could also have a feeding problem, as the 45-70 chambered rifles are set up to feed the longer cartridge.

The actual base diameter of the 45-70 cartridge is the same as a .475 Linebaugh and .480 Ruger, the .45-70 case is what the .475 was originally derived from. Odds are pretty good you would split evey case you fired. With the small rim size on the .45 Colt and the likely split cases you might even get a bit of gas leakage in the rearward direction. I'm not saying you can't do it, but it would not be a good idea for that reason alone in addition to what the others have said. It is never a good idea to shoot a cartridge in a firearms that is not specifically chambered for it. The 45-70 is a slightly tapered case where the .45 Colt is not, so even though the bullet diameters are somewhat similar it is not the same thing as firing a .38 or .44 Special in a revolver chambered for the magnum counterpart of the shorter cartridges.

There's a couple more problems. The maximum rim diameter of the .45 Colt isn't much more than the base diameter of the .45-70. You could end up with the rim of a .45 slipping into the .45-70 chamber and out of reach of the firing pin. This slop also will result in excessive case expansion. That's hard on brass and it may split on you. Worse case, depending on the rifle model, is a face full of hot gas and melted brass.

Bye
Jack

Hornady manual shows the 45 Long Colt rim diameter at 0.512". The 45-70 rim diameter is .608". The case diameter of the 45-70 just ahead of the rim is 0.505". That's not far off from the 0.512" Colt rim, and the Colt case dia is 0.480". So, I think you'd be in danger of the Long Colt slopping over to one side of the 45-70 chamber and very likely having an unsealed breech. I wouldn't do it!

454 casul???????????
it's way past my bed time and this all may be a dream .
but i recall reading that .45 lc can be fired through the 454 casul. is this true???
thanks in advance.
dogman

please relpy i'm about to pass out. anyone????.lol

The Casull and the .45 Colt share the same relationship as the .38/357 Mag, 44 Spec/44 Mag, etc, etc, etc. The cases are the same dimension with the main difference being length, as far as external dimensions are concerned.

does anyone know if 45. long colts cam be safely fired out of a marlin 45-70 gov.
i undderstand that it can be done out of a 45 casul.
and if it can, does it reduce barrrrrel life?
thanks in advance,
dog man
p.s sorry if this is a silly question

DO NOT TRY THIS, you will have catistrophic case failure.

No the 45-70 is a .458 cal and the colt is .451 cal.