450 Bushmaster Reloading

[65bee]

Have been at the reloading game for over sixty years but have come up against a new situation that has me confused. I have just picked up a new Ruger American Ranch rifle in 450 Bushmaster at a 'going-out-of-business' sale of one of our local gun shops. I knew little about the cartridge at the time, but assumed it might be a good platform for shooting cast bullets. I have found that the cartridge uses small rifle primers, and that this has caused some problems in reloading? The biggest issue sems to be inadequate ignition, i.e. squib loads, with certain loads/powders. Many reloaders have advocated the use of CCI #41 Mil-Spec primers only? Would like to know what experience forum members have had with this cartridge. I do not intend to max out this round in reloading. Want to shoot mainly cast bullets in the 1400 fps range and maybe jacketed bullets at 1800 fps or so for whitetails. I have ordered some dies, but am unsure if the issue of primers will be a problem? Thanks for any assistance.

[Bill in Oregon]

Had an AR in this chambering that was extremely accurate. Will try to find my notes. Brass was Starline.

[ywaltzucanrknrl]

65Bee. Pretty sure the reason they tout the military style primers is because AR platforms "can" slam fire. Most AR shooters will use a primer with a heavier cup like CCI 450's, R-P 7 1/2's or the CCI military primers to avoid the "chance" of a slamfire. Where your rifle is a bolt gun you don't have as much to worry about with primers.
I use R-P 7 1/2's and CCI 450's in my 450 Bushmaster in an AR platform and they work fine.

I've shot several hundred rounds of ammo out of it with cast bullets since I bought it from Bill. I've had no squibs. I've used mostly some old 4227 that I want to get burned up. I've shot 250's to 325's in the cast bullets and some have shot very good, others not so much. Feeding with some different bullet profiles in the AR has been an issue, but the bolt gun you have may feed well with ones my AR does not feed well with.

I realize a couple hundred rounds is not much, but I've had no problem.

The cartridge does headspace on the cartridge lip and that bothers me a bit (in my mind I suppose more than in practice) so I'm careful with the crimp to not over do it.

I tried Unique but it wouldn't cycle the action on the AR, but the rounds shot well, I've also tried 4198 and Rl7 with some success---accurate and the AR cycles.

Where you don't have the cycling issue or the slam fire issue, I think you will find the cartridge easy to load for if you pay attention to the crimp and other reloading standard practices.

[Bill in Oregon]

A target with the second Bushmaster upper, also from Bear Creek, which is the one I believe Jon bought from me. I used the CCI # 41.

[65bee]

Appreciate the feedback fellas. I especially was interested in the comment regarding using Reloader 7 powder. This is one of my favorites for many other calibers as well, and I have a fair supply. When the dies arrive and I have an opportunity to try out some loads, will report on the results.

[GunnyMack]

I've used nothing but Federal AR Match primers. 4227, Lilgun, 5744 have all worked great for my AR. I've only used jacketed.
Smaller charges of powder behind some cast bullets I could see being problematic since it uses small primers , smaller charges in a big case.

[6pt-sika]

I had a 450 Bushnaster in an AR thing shot great with factory or my handloads . Killed a deer or two with it and lost intrest shortly thereafter .

[2ndovc]

I have a Windham AR in .450 and a Mossberg patriot as well. Both rifles are outstandingly accurate. I sighted in the Mossberg with factory sub sonics ( I had a pile of it and the reason I bought the bolt action).

Handloads with IMR 4227, H110 and standard small rifle primers have had created any issues with cast or jacketed bullets. I bought some Lil'Gun to try, but haven't gotten to it yet.

jb