I wouldn’t be looking at this for accuracy per-se…450 BM basically has the ballistics of a thrown rock. Mine’s purely a deep-brush pig killer, and I can’t imagine actually taking a shot on game much past 50 yards or so.
My vote would be to spend the extra money on a higher end upper…or better yet, roll your own.
Had my 10.5” 450BM barrel spun up off a Satern blank (I think it was a Satern barrel anyway, might have been a Tromix) by Trident Armory back in ‘19, but it doesn’t look like they do that kind of work anymore based on their website; looks like they mainly just do training and stuff now.
Built it up on a spare billet upper receiver I had, after I opened up the ejection port for that big ass case:
Dremel FTW! LoL
If you build your own, please just make sure you get a receiver with a large enough ejection port already machined in, so you don’t wind up with a hack job like I did to this poor receiver. I did leave the little detent tab at the top so I could leave a dust cover on there to hide my shame!
Looked OK after Cerakote at least…
…and even though it’s only a 10.5” barrel, I went with a 15” hand guard to tuck much of my huge ass Bowers 458 vers can under there too. Nothing like an 11” long can hanging off the end of a 10.5” barrel!
I’ve punched a fair bit of paper and shot a couple pigs with it, and it’s a hoot to shoot! Makes big holes!