Current state of the 450 bushmaster?

[Jayhawkhuntclub]

On paper really like this round. But I see very little new reloading data for it; especially for cast bullets. It seems like a affordable alternative to the 458 socom and 50 beowolf. But it seems like this cartridge is flat lining. The forums that cater to it seem like ghost towns. Wish there was more discussion on the topic. Any thoughts?

 

[CarJunkieLS1]

If or when I ever get a chance for a big bore AR it will be the .450 BM. Ammo is available but rifles and uppers seem to be scarce. You don't see them for sale used either...that should tell you something.

 

[WVinMN]

I own a Remington (Bushmaster) 450 BM that I picked up at Cabelas several years ago. It's been modified with the addition of a Geissele trigger, Hogue forend, Mako adjustable stock and other odds and ends. I reload for it using Hornady FTX or Barnes TSX bullets. Reloading data is available from Hornady, which essentially duplicates the factory offering. I acquired data for the Barnes TSX from a combination of internet searches and trial & error. Barnes actually markets a TSX bullet for the 450 BM, however, when I called and asked for data, they hadn't finished developing their own in-house loads as of this past August. The gun shoots well and does a great job on wild hogs, but it's quite sensitive to cartridge length. Also, I had to purchase three different magazines to find one that was consistently reliable. As far as cast bullets go, wouldn't that cause problems in any firearm designed with a direct impingement gas system?

 

[Jayhawkhuntclub]

As far as cast bullets go, wouldn't that cause problems in any firearm designed with a direct impingement gas system?

No, I shoot cast through my 300 BO AR all the time. Most of them are gas checked though. Never had a problem.

 

[FrankenMauser]

I prefer .458 SOCOM, myself.
Rifle cartridges that headspace on the case mouth are a big no-go for me. Add the semi-auto action, and I'm running the other direction.

Otherwise... .450 BM is decent on paper.


One thing to keep in mind about the cartridge, and other niche cartridges:
They're not main-stream, popular cartridges.
There's a lot of talk, but few people actually buy the barrels/uppers/rifles.

And, forums that cater to niche products don't actually have a lot to talk about. So when you combine low ownership numbers with just a fraction of those owners participating in discussions on internet forums, there just isn't much to see.


Cartridges like .450 BM, .458 SOCOM, .475 Rhino, .277 Wolverine, and any of the other "latest and greatest" (or just different) AR wildcats have a lot more discussion, than actual production numbers.

Take .475 Tremor as an example (.458 SOCOM necked up to .475 caliber, with some tweaks to the chamber for handgunbullets):
If you search Google for ".475 Tremor", you'll get over 3,300 hits.
Yet... There have only ever been 13 actual .475 Tremors produced, as well as two known .475-458 SOCOM 'hybrids'/'copycats'.
Marty ter Weeme (Teppo Jutsu) built the first one for Tony Rumore (Tromix) in 2001, which was later sold to a private party in 2003.
Then, Tony decided to mess with .475 Tremor again, and ran a dozen 14" barrels with matching engraved (stripped) upper receivers in 2014.
To date, only six of those barrels have been sold (one of which was for Tony, himself).
And two other parties on the 458socomforums decided to use .475" barrel blanks, .458 SOCOM chamber reamers, and .475" throating reamers to make one-off chambers to mimic .475 Tremor.

That's it.
There are only seven .475 Tremors, and two 'copycats' out there. But, somehow, we owners (I have one of the six sold 2014 barrels) and other people that wanted to talk about the cartridge have been responsible for over 3,300 hits on the internet.


Lots of talk.
Very few buyers.

 

[Dirty_Harry]

I love my .450 bushmaster. I bought the upper slightly used from a guy on M4carbine.net. I mainly bought it because it is now legal to hunt with in the shotgun zone of Michigan, but I cannot see many instances of me wanting anything else. The factory bushmaster upper is MOA accurate, even with my poor shooting. Ammo is fairly available.

Recoil isn't bad at all. It doesn't seem to have quite as much power as the other big bore options, but for 200 yards and less I doubt you'll tell a difference.

 

[Jayhawkhuntclub]

Rifle cartridges that headspace on the case mouth are a big no-go for me. Add the semi-auto action, and I'm running the other direction.

FrankenMauser: Could you elaborate on why you feel this way? My AR9 runs like a champ. But of course the 9mm isn't exactly a rifle cartridge. I'd like to hear your reasoning. Thanks.

 

[44 AMP]

Historically, RIFLE rounds that headspace on the case mouth often have issues in the larger calibers, and semi autos increase the trouble.

Smaller, shorter rounds like pistol rounds work fine, but as they get longer, and larger, the small area of case mouth contact with the chamber is not always enough to positively headspace the round.

The combination of a heavy bullet, long case, (heavier than pistol cases), tiny ledge for headspace, and the '"running start" of the round being slammed into the chamber (particularly with a semi auto) often defeats correct headspacing.

.30 Carbine works well, 9mm & .45ACP work well, cases up to magnum length pistol (approx. 1.3") work well in handguns. LONGER cases like .308 or longer (2") had shown issues when using straight or nearly straight cases in .40 or larger calibers.

They can work, but sometimes have issues, and so many people simply avoid them.

 

[FrankenMauser]

44AMP covered it pretty well.

 

[WVinMN]

Maintaining correct headspace is a potential issue with the 450 BM. Which is why it is imperative that you trim your brass to the correct length and taper crimp ONLY! Unfortunately, the base Hornady die set only comes with a seating die capable of roll crimping (a no-no with the 450 BM). You have to purchase the taper crimp die separately. Finally, only expand the case enough to just seat the bullet, and skip belling the case mouth. Most bullets (including both the FTX and TSX) have a small heel at their base, which is adequate to correctly align the bullet when using a single stage press.