AR cast boolit shooter is looking good!

[BD]

I got my .450 Bushmaster back from the smith yesterday where it had been to have a custom Gentry "quiet brake" installed to make it NYS legal. I slugged the bore and then dropped 3 lead balls in and tapped them against a chambered case filled with WW alloy. The good news is that the chamber on this thing looks just about like a .45 acp. .451 bore with just .1 inch of .453 "throat" before the lands start. It looks like I'll be able to seat cast boolits right into the start of the lands same as a 1911. With the 24 twist and case volume of this round Quickload is telling me I should be good be good for anything from the BDacp as a plinker at 800 fps, to 300 grainers at 2,000 for killing things. Unique looks perfect for the low end loads and anything in the H110/296/Lil Gun range should work for the thumpers.

Now I just need the group buy lowers to come in so I can get on with the break in and some load development :)

BD, (smiling in the land of the liberals)

[crabo]

I am watching this with interest as I need to come up with a new caliber for my new lower. I have a 9mm and a 223 and what you are doing seems like a logical progression unless I stopped and did a 6.5 or 6.8 on the way to the .450.

How does this cartridge compare to a 45/70 in the guide gun configuration? I just got the group buy 405 mold for 45/70. Since I don't have Marlin yet either, I could go either way.

Thanks,

[BD]

Ballistics are about the same as the 45-70 loads for the Winchesters and Marlins. Saami max pressure for the .450B is 40,000 psi. 300 grainers at 2,000 fps, 400 grainers at 1,900 out of an 16 - 20" barrel.

If you're looking for an elephant gun, I'd go with the .458 socom for the longer throat, faster twist, more powder capacity and big selection of condoms/solids.

I chose the .450B because my interest is in shooting cast, and 400 grainers seem like they'll be more than heavy enough. The slower twist, very short throat and smaller case capacity look good to me. Except for the length, looking down the tube of this rifle you could mistake it for a 1911 barrel.

I'd considered the 6.5 Grendal, and I may build one some day. But I have other bolt rifles that will do what that cartridge is designed for, better. I don't own any large bores, or any rifles that seem well suited for cast boolit hunting, so the .450B made sense to me on several levels.

BD