I just recently bought a Bulgarian Arsenal AK. From what I was able to find, it appears to be a Blue Ridge build. It has a non matching parts kit (I'm assuming original '50s Hungarian). Overall the gun is in really good shape 85-90%. My understanding is that when these rifles were originally built they had muzzle nuts on them: is that true for all of the Blue Ridge builds? My rifle has a slant brake, which makes me wonder if it was done by the previous owner, or if it might have an American barrel. How would I be able to tell where the barrel was made? I'm finding price ranges on SLR 100H's that range from $800 to upwards of $1,300. Where is the market at today on these guns? Thanks for the help.

I also have a Blue Ridge SLR100h and mine has the muzzle nut. It was originally spot welded to be ban compliant but the weld has been grinded off so the muzzle nut unscrews.
When you unscrew the slant brake are their any reminants of spot weld where the front sight base meets the barrel? If so its a dead give away of the original hungarian AK55 barrel. As far as I know none of the SLR100h series of AKs made by Blue Ridge or Gordon tech have US made barrels. Honestly I do not think US made  milled barrels were made back then either. I hope this helps

I also have a Blue Ridge. Mine was made from an all #'s matching kit. My barrel was screwed in. Not pressed in with a pin. Back in the day when the original milled AK's were made, there was no slant brake. They used the thread protector. These guns came with the protector tac welded on, as they were built during the ban. Great gun. One of my favorite. GARY

I pulled the brake off, didn't notice anything wrong with the threads. Couldn't see where there could have been a weld.

Your barrel should still be pinned in place. Blue Ridge welded and covered them after assembly. Check for slight discoloration where the pin should be. To my knowledge they should not have screwed any of their barrels in.