450 Bushmaster from???

[dh2]

I am looking to get in to 450 bushmaster and my reading tells me the parent case is 206 Winchester, With that in mind could I simply cut down brass like 308Win and 243win to lingth or would this cause me to end up with the case mouth being to thick??

[brstevns]

308 win 243 , 30-06 etc will not work. parent case is the 284 Winchester.

[cwlongshot]

Haha its not made from "206"?

As stated its parent case is a 284 Winchester.

[brstevns]

If thinking of the 45 Raptor you can use 30-06, 308 etc. to form brass. Like the 450 bushmaster it uses a 452 diameter bullet

[lar45]

The 450 Bushmaster has a small primer pocket, and the 284 Win has a large primer pocket. So depending on where you want to end up, you can either buy 450 brass or cut down 284 cases.

[Pipefitter]

450BM and the 284WIN both have a rebated rim, where the rim of the case is smaller diameter than the web.
Lots of good info at 450Bushmaster.net

[wolfwing]

I have about 50 284 cases that I collapsed the neck on when I was trying to go down to 6mm. If I trim these off to the proper length will I need to inside neck ream them to run a 300gr bullet??

When I was making 475 Wildey brass from 284 Win, I had to inside neck ream them for any bullet heavier than 230gr. What a PITA that job was. The Wildey and all of my formed brass went down the road several years before 475 bullets were common and Starline was making brass for it.

[lar45]

I have not cut any down, but I think you can just cut at the shoulder, trim to length and load.