450 Bushmaster HALP!!!

Infamous1

Well-Known Member
2A Bourbon Hound 2024
2A Bourbon Hound OG
Supporting Member
Multi-Factor Enabled
Joined
Dec 28, 2017
Messages
3,303
Location
Pittsboro
Rating - 100%
33   0   0
20190310_202441.jpg 20190310_202417.jpg 20190310_202407.jpg 1552264518267167599759.jpg 1552264617815-1551319553.jpg images (1).jpeg
Got a 10.5" 450 Bushmaster upper from Bear Creek (I know I know) with dreams of shooting piggy pigs. I have two lancer 20rd battle mags and tromix followers, 2 20rd SS mags, one SS 30rd mag and one lancer 10rd battle mag (notched the front of this mag) put chambers tactical single stack followers in the latter four mags. Shooting Hornady 250gr FTX factory loads. Same issue with all the mags. Bolt won't seat 50% of the time on follow up rounds. Cases look pretty boogered up, gaulded on some of them, had to snatch on it pretty hard to get a fresh round out of the chamber that wouldnt fire. Trigger snapped but it did not fully strike the primer, it is the last casing pic. Here are a few pics.
First pic is of two rounds put into a mag and cycled by hand. The rest are empty casings cycled by the gun.
 
View attachment 112294 View attachment 112295 View attachment 112296 View attachment 112299 View attachment 112300 View attachment 112301
Got a 10.5" 450 Bushmaster upper from Bear Creek (I know I know) with dreams of shooting piggy pigs. I have two lancer 20rd battle mags and tromix followers, 2 20rd SS mags, one SS 30rd mag and one lancer 10rd battle mag (notched the front of this mag) put chambers tactical single stack followers in the latter four mags. Shooting Hornady 250gr FTX factory loads. Same issue with all the mags. Bolt won't seat 50% of the time on follow up rounds. Cases look pretty boogered up, gaulded on some of them, had to snatch on it pretty hard to get a fresh round out of the chamber that wouldnt fire. Trigger snapped but it did not fully strike the primer, it is the last casing pic. Here are a few pics.
First pic is of two rounds put into a mag and cycled by hand. The rest are empty casings cycled by the gun.

I always used metal GI mags with the followers in them. try one and see what happens.

But buffer and spring, what are you using?
 
Rounds not seating compltely or sticking in a new chamber suggests you might need to polish the chamber. I too am interested in your buffer system and gas block alignment. It looks like you have a couple of issues here. Polish the chamber really well and check you gas block alignment. Try a different mag as suggested earlier and let us know what happens.
 
Last edited:
No idea on buffer and spring, I just put it on a pistol lower I picked up off of here. I will polish the chamber and see what buffer and spring I have. Heavier is better for this application I am assuming?
 
Also forgot to add, I am running this with a LAW folder so it has the bolt extention on the rear of the bolt.
 
BCA sent me a return label and said they would fix it or replace it with one that would run. They said they have approx a 4 week turn around on issues like this but it would be resolved. It is on it's way back.
 
If I decide to build a dedicated lower for this upper what are some suggestions on buffer weight and spring combinations? Would LAW folder have any negligable effect on it? Not dead set on the LAW on a dedicated lower but I do like the idea of a backpackable big bore.
 
BCA sent me a return label and said they would fix it or replace it with one that would run. They said they have approx a 4 week turn around on issues like this but it would be resolved. It is on it's way back.


Sounds like a good plan. I looked over this, and its way out of my area of expertise, and above my pay grade, so nothing to offer. I think what you are doing, is exactly what I would do. I am not very mechanical, and they don't allow me any serious tools anymore. You should see the things I can tear up with the right tools! I am handy with a bastard file too, until I file things down to shavings...... I do get carried away.
 
@Infamous1 do big bore ARs have free floating firing pins like the 5.56 models? The picture of the dimple in the primer actually looks normal for a bullet that has been properly chambered by a rifle with a free floating firing pin.
 
It was a really light strike compared to the other rounds that actually went off. I was able to see the bolt move forward slightly when I began the manual extraction process on the live round.
 
Make sure to ask what was wrong and keep us updated. Looking at the cases it appears to have some real issues!
 
4 week return?
Bear Creek is located 20-30 mi south of you.
If you’ve the time, take a drive S.

Oh yeah I know exactly where it is located, I just have alot of stuff going on right now and it was not worth my time to see it through in person. Its already been mailed and the reason I built it initially is already ground into sausage and in the freezer. I will update as I receive info. I do feel that the setup I had on the .450 with the Leupold 1.5x4 scope, offset flip up sights and a single point sling would have been absolute perfection for everything I encountered down there in FL though .
 
Well recieved a brand spanking new upper assembly from BCA today. Just said we have decided to replace it. The new one looks overall really good. The picatinny rails actually fit my Nikon mount this time with no issues, the charging handle actually locks closed without any issues, the barrel lugs do not have any sharp edges and the chamber looks smooth. I am initially impressed. Got the scope mounted and bore sighted and got the back-up sights mounted. I am going to try to get it to the range and see how it runs in the near future.
 
Back
Top Bottom