I recently purchased a 300 SPS for a 9" BCM. Needless to say, I needed a Surefire muzzle device to make it work with the pistol.

I had someone at my local shop install the muzzle brake, and when I got home and really looked at the thing, I noticed he didn't use the beveled spacer and only one shim. Cool, I get one shim may only be necessary to get it timed correctly, but the shim was sticking out on one side and the lack of the beveled spacer makes me concerned. I ordered some Surefire bore alignment rods, but the shoddy job has me wondering.

Should I take it someplace else and have them reinstall it with the beveled spacer and get the shim more aligned with the barrel? Or does a .300 BLK BCM barrel not require such detail (I only ask because I don't know if 5/8-24 barrels are a different animal)?

Thanks.

Sounds like a shoddy install. I don't know what happens if you don't use the beveled spacer.

But this 5 minute video from the VP of Surefire makes the install seem super easy. The shims should be even on all sides. Watch this video.

https://www.youtube.com/watch?v=CjA9-VbmrXA

The beveled shim serves as a spacer for barrels which don't have a releif cut.

I have that same Can and it mostly gets used on 9" BCM in .300 Blk...  
If you are shooting .300 Blk subs, you'll love it.
99.9% of the time I shoot 220 Gr subs out to just under a 100yards at a string of Steel plates I set up out back.. Its a hoot.

A few of my friends have built .300 blks after shooting mine.

I'd give them a call, email them pics shown what they did it wrong and that's why you have to do it right.

I'd just do it yourself just as shown in that video. You can remove your handguard, use 2 wood blocks as barrel vise blocks and install it properly.

Yeah that's part of the reason I went with the 300 SPS. I've heard great things. Those subs seems to be hard to find nowadays.

With the shoddy install, I will definitely re-do it myself. Might need to snag a heat gun, but I was told that the installer "has done quite a few of these" in his time. Obviously it was not done correctly. One tiny shim between the barrel and muzzle device.
Since i'm here, is there anything I should look for damage-wise when I take it off?