.455 dia. bullets in 45 Colt brass

chiefdave · #1 10-08-2020, 04:20 PM

I have a .455 S&W 2nd Model that has been converted to 45 Colt and as you can guess the .451/.452 bullets keyhole. Has anyone tried .455 bullets in fire formed 45 Colt brass? The cylinder is a later one (heat treated) and will still chamber and fire 455 Webley.

rockquarry · #2 10-08-2020, 04:40 PM

I'm not exactly sure what you are asking, but I've used .456" or maybe .457" cast LSWC bullets in my S&W 25-5 with oversized throats. I used Winchester .45 Colt brass without problems.

6string · #3 10-08-2020, 05:18 PM

It's really a question of your reloading die specs. Once you size your brass, it doesn't matter how it was fireformed.
Most 45 Colt dies ( especially carbide) size the brass undersized. Your expander plug could be for anything from .451" to .455" bullets.
I have several dies sets in 45 Colt and 44 Special, and usually have to lap them to different dimensions to get them right for cast bullets.
Some of the die makers know this but don't care. My terrible Redding 44 Special dies sized the brass down for a .424" case mouth. Redding said that was in spec. So, I lapped them out .005".
This was little trouble for a steel die. Carbide?.....forget it! Straight walled pistol cartridges aren't straight. They taper. But, carbide dies size the whole case to under the smallest diameter. They are a gimmick and not worth anything, (except maybe very short 45 ACP cases.)
.455" bullets might be perfect for your revolver. But, if your brass is grossly undersized because of your die set-up, the bullets will be distorted when you go to seat them.
When that happens, you will never get the true performance capability and might end up with the same problems: keyholing, leading....

Jim

glowe · #4 10-08-2020, 05:55 PM

Standard 45 Colt bullets are .454", so hardly any difference upsizing to 455" bullet. I shoot .454" in my 455' without any keyholes. I also have a 455 MK II bullet mold and they do work best for me. Remember, 45 ammo was hollow base, so the skirt allowed for expansion and good contact with the rifling of a 455 barrel.