California legal Yugo SKS muzzle break issue

I picked up a California legal SKS today thinking I was getting a decent rifle. Upon closer inspection I'm now wondering about that.

The grenade launcher was removed and a muzzle break installed and spot welded.

When purchased the bore had a slight layer of cosmoline in it while allowing the rifling to be clearly seen hid what appears to be a too deep weld which corresponds to all outward appearances the outside weld. The mark on the inside is very slight, does not appear to be a crack but a slightly raised surface that isn't noticable unless really looking for it. It goes about 1/3rd around the inside of the barrel.

The bore is very bright and shiny and otherwise the rifle looks to be in near new condition.

My concern is this thing blowing the end of the barrel off or blowing the muzzle brake off because of the weld.

Am I being over cautious?

I could easily cut the brake off and re-crown the barrel but would prefer having the break on if it is not a safety issue.

Not knowing much about these things I would assume firing a few rounds would remove the raised surface........or blow the end of the barrel off.

Any thoughts?

I should point out that I don't live in California and have no restrictions in my state regarding the grenade launcher/muzzle break.

Is it actually a raised area or just discoloured? Do you feel a tight spot if you run a patch through the bore?

What it looks like is a very fine hair and since we have a golden retriever and his hair is everywhere, that's what I figured it was. But it doesn't come out. There is no binding with a patch, you can't even see it unless the light is very bright, probably why I missed it at the show. My close eyesight is going too so when I look in it with my glasses on, I don't see it. With them off and a bright light I see it. It does cross the lands and grooves with the same effect.

The bore in this rifle is very bright, might be the brightest bore I own and I have a few new rifles. If you just glance in the barrel, you aren't going to notice it.

So it could simply be discolored but it just has a look to it that it's slightly raised, not the entire barrel like it would constrict a bullet but just this tiny line area.

It would have to be something from the weld, maybe the heat discolored it, or maybe burned some of the cosmoline into the metal somehow. Worst case it burned all the way through and what I'm seeing is some sort of crack from that. I sort of doubt that, it's too narrow and regular. It's just the width of a very fine scratch. I see scratches of this type in my other bores but they are running parallel to the rifling, not across them.

After studying this for about a week now, I've come to the conclusion that it's discoloration from the heating process of welding the muzzle break on.

I scubbed it a bit with a cleaning brush and while unable to eliminate it, reduced it on the one end. The bore has a near mirror finish and I think that's the only reason I'm noticing it at all.

Have you shot it at all, yet?

No, I don't even have any ammo for it yet. My local gun shop is closed and being sold which surprised me as I go in there once a week and no mention was made of it.

I had planned to take it there to go over a few options and have him look at it, now I no longer have that option.

I'm thinking about the spring loaded firing pins, anyone have any experience with them? Supposed to prevent chain or slam fires. Not that I'm going to have a dirty firing pin, I was able to get that pesky pin out and clean it thoroughly. It at least sounds safer.

I'm looking online for ammo. Looks like Sportsman's Guide is my best bet at the moment. Looks like 7.62x39 has dried up. I had an easier time getting 7.62x54 and I believe that is actually cheaper right now.

My local gun shop had a full case of it sitting there, I don't remember what he was asking for it but I was going to check on that too.

Sign says they will be re-opening soon, but owned by who and how soon is "soon".

Sounds OK to shoot.