.450 Bushmaster

[guntha45]

Does anyone load for .450 Bushmaster and have experience converting .284 Winchester brass? Here is why I ask-
Years ago, I had bought some loaded wildcat 6mm/284 ammo for a rifle I built. The ammo was necked down .284 Winchester brass and the deal was too good to pass up. Turned out that it was too good to be true- for usable 6mm/284 ammo. Almost all the necks of the brass were cracked and I had 300 rounds of it. I pulled all the bullets and salvaged them and the powder (H414). I never throw away brass, so into a box the brass went.
Fast forward almost 20 years and I have an AR and a Ruger American in .450 Bushmaster.
I came across that .284 brass and now have a purpose for it. It was a bit dark and dingy so I wet tumbled it with stainless steel pins. It looks new now!
I bought a mini cutoff saw for $35 off eBay to speed the process of rough cutting the neck and shoulder off.
I've got that done, got the brass run through the sizer/deprimer, and the inside neck sizer.
I've got my trimmer set up to trim to 1.700". I just have to run them through that now.
It will be interesting to see is the outside diameter is too big once a bullet is seated. I'll make a couple dummy rounds and see if they chamber ok in my rifles before loading any.

 

[Alan]

That’s some serious brass resurrection, turning a 20-year mistake into .450 fuel is next-level commitment

 

[HWB13]

If I recall , the 450 head spaces off the case mouth, I could be wrong. If it does the case dia may be to your advantage

 

[guntha45]

Yes, it does headspace off the case mouth, like a .45acp but twice as long!
The thickness is better, to a point, then it can make the outside diameter to large to fit in the chamber.
We shall soon see if it will. I just have the final trim and then I'll make up a couple dummy rounds to see it they will chamber.

 

[HWB13]

One thing I was thinking after I posted was the reason I went with the 458 Socom . It has a ever so slight case taper. One of the factors with the 450's totally straight case was some case sticking, watch for that.

 

[guntha45]

I got the 215 pieces of .284 Win. brass reformed, trimmed, full length sized, inside neck sized, and polished.
I made up 2 dummy rounds with 2 different bullets to see if they would chamber correctly. They both chambered well in my AR but the bolt would not close on the .243 Ruger American I rebarreled to .450 Bushmaster.
I'm quite sure that I just have to reset the headspace on the Ruger American. It is an easy process as there is a lock nut that holds the barrel in place once it is screwed into the receiver to the correct headspace. I didn't have a headspace gauge so I had used a dummy round made from new Starline brass that is a hair shorter than the 1.700" specified brass length. The recommended trim length is 1.695" so I split the difference and trimmed this lot of brass to 1.697/1.698". I saw that the barrel markings were not indexed, indicating that the barrel was screwed in too far but that is where it stopped on my dummy round.
I'll let you know how it works out.

 

[guntha45]

Just got back from the shop in my garage and got the headspace adjusted on the Ruger American.

 

[HWB13]

Maybe a silly question but did you load a factory load into the American? If you did the adjustment would be a problem if you went back to factory ammo.

 

[guntha45]

Maybe a silly question but did you load a factory load into the American? If you did the adjustment would be a problem if you went back to factory ammo.

Not a silly question, it could be a problem, but I don't shoot any factory rifle ammo apart from .22lr, .223/5.56 FMJ, and .308/7.62 FMJ.
Considering the price of odd ball factory ammo and having been reloading for 50 years I have accumulated a lot of dies and components there is no need to buy factory ammo, except for rimfire and 5.56 ball. I have got a good stock of 7.62 NATO and .308 win FMJ that I got on sale some time ago.