Josh
Well-Known Member
It's been a long time since I logged in or posted, but I'm still kicking! There has been a lot going on in my slice of paradise which has kept me from my hobbys. But, I have been working on a back burner project as the time permits.
Today I present to the group my 450 Bushmaster build. This cartridge normally runs at 38K psi but with the Savage 10 action it will safely handle the 62K psi of a 308. So I plan on working up some loads in the 45 Colt range as well as standard 450 loads. But I also plan on making a few nosebleed rounds just for the experience.
So I made a cast of the chamber and found it to be about perfect for what I intend. The throat is generous in length but shaped very well, the bore is also a hair tight at 0.449". Here is a crude drawing of my measurements.
Yeah, I know I drew the rifling as left hand while it is right (crude drawing remember?) The twist is also not the normal 1-24" that comes with a 450 Bushmaster but the 1-16" normally found on the 45 ACP. I believe this will rob me of some velocity, but the versatility to shoot anything from 185 gr HP's to 550 gr cast is appealing.
Now, I have seen that this cartridge normally uses generous amounts of Lil' Gun and H-110 but when I start loading for the standard power loads I believe we will use 458x2" American data and start with IMR 4198, IMR 4895 or IMR 4064. I would prefer to keep the launch as soft as possible. With all this said, I think I will try the 3 Lee moulds I have in my 45 cal collection, the 230 TC, 255 RF, and 300 WFN.
So, hello again and what do you think?
Today I present to the group my 450 Bushmaster build. This cartridge normally runs at 38K psi but with the Savage 10 action it will safely handle the 62K psi of a 308. So I plan on working up some loads in the 45 Colt range as well as standard 450 loads. But I also plan on making a few nosebleed rounds just for the experience.
So I made a cast of the chamber and found it to be about perfect for what I intend. The throat is generous in length but shaped very well, the bore is also a hair tight at 0.449". Here is a crude drawing of my measurements.
Yeah, I know I drew the rifling as left hand while it is right (crude drawing remember?) The twist is also not the normal 1-24" that comes with a 450 Bushmaster but the 1-16" normally found on the 45 ACP. I believe this will rob me of some velocity, but the versatility to shoot anything from 185 gr HP's to 550 gr cast is appealing.
Now, I have seen that this cartridge normally uses generous amounts of Lil' Gun and H-110 but when I start loading for the standard power loads I believe we will use 458x2" American data and start with IMR 4198, IMR 4895 or IMR 4064. I would prefer to keep the launch as soft as possible. With all this said, I think I will try the 3 Lee moulds I have in my 45 cal collection, the 230 TC, 255 RF, and 300 WFN.
So, hello again and what do you think?