45 Colt S&W Mountain Gun

[MePlat]

If it is okay to run 24 grs. of H110 with a 260 Keith bullet in them would it be okay to back off 1 gr and go with the RCBS 270 SAA bullet?
How much would one back off when going from 20 gr A2400 with the 260 Keith to the RCBS 270 SAA bullet?
I really like the RCBS 270 SAA bullet and would like to use them.  I have them that are cast Lyman #2 ally and 1-16 tin and lead.  They weigh 278 cast of #2 alloy.

[Ken ONeill]

It's your gun and any load that makes you happy is fine with me, but I consider both of the loads you mention too heavy for the Smith, and wouldn't use either of them out of consideration for stretching the frame.

[Graybeard]

I agree with Ken that's way hotter than I'd load for the S&W.

[Ak.Hiker]

John Linebaugh has an article with load data on the Smith and Wesson model 25 45 Colt on Handloads.com. The article would be worth a look. If it was me I would stay close to his starting loads in the Smith. I have a fine old Smith and Wesson 1955 in 45 ACP. My favorite top end load in my gun runs a 250 hard cast at about 950. I would love to have a Mountain Gun in 45 Colt. It would be a fine woods gun.

[Lloyd Smale]

to me id run that bullet with 20 grains of 4227 and maybe 22 for an occasional hunt and call it quits. I agree with the others that your pushing the envelope with your loads. Your gun isnt going to blow up but your going to eventually shoot it loose. I know john uses loads like that for hunting is his but he doesnt shoot a steady diet of them. He most runs his at about 900 fps with a 250. Keep in mind too that John can fix his own guns and when they do shoot loose he can easily fix them. If you really need power like that either swap it for a smith 29 or if your stuck on a 45 buy yourself a large frame ruger. Keep in mind too that a 250-275 grain bullet at 900-1000 fps will do alot of killing. Ive seen animals as large as a 1000 lb cow buffalo shot with that level of load and it performed real well. Ive personaly taken a number of deer bear and pigs with loads like that in 45 colts 44specs and 44 mags and have never lost an animal shot with one.

[MePlat]

Quote from Linebaugh:  "To date my oldest and most used S&W .45 Colt has probably taken 5,000 plus loads. Half of these have been 24.0 gr H-110 with the 260 Keith."

Never meant to use loads like that constantly just ocassionally.  I know that the MG won't last as long at 32000 cup as it will at 28000 or 24000 or 14000.
The same gun won't last as long in 44 Mag at 40000 cup as it will at 32000 cup or 28000 cup etc. etc.
In shooting large quantities 18000 to 20000 cup should be fine I would assume.
Would that be reasonable?