Ye another AK74 muzzle break job

[modrisco 16]

Back in August I decided to add a AK74 style break to my 7.62 Saiga; I'd already done the basic FCG/PG conversion. After reading how others on the forum managed their MB project, I decided to cheap out and not go the Bulgarian FSB route opting to keep the Saiga FSB, instead. My rifle is a '06 model with the civilian stepped barrel, and did not have threads from the factory. Started with the pipe cutter approach to remove the shroud, but wound up using a Dremel. I removed the shroud back about 5/8", but went a bit too deep (see picture) which wasn't an issue once the threading was complete.

 

I ordered an adapter from Krebs, and a AK74 adapter (AK140US). Once the adapter arrived from Krebs, I started thinking about how to properly index the MB. Didn't like the idea of it sitting out so far from the FSB base, so I cut the shroud back the full 1" to the base. In addition, the adapter did not have indent locations, so I ordered a Bulgarian adapter that did have indent locations. Unfortunately, the K-Var MB didn't match up with either the Krebs or Bulgarian adapters; it would only partially screw in. After talking with both Krebs and K-Var support, I decided to send the K-Var MB back, and order the AK74 MB from Krebs which matched up with both adapters once it arrived.

 

Bought a piece of brass rod at the local hardware store, and drilled a small hole into the FSB base. Cut the brass rod to length, and added a small spring behind it. Used some blue Loctite when I screwed on the adapter, and some double density yellow Teflon tape wrapped around the adapter before screwing on the MB. Although there's a small gap between the FSB and MB, everything is solid... no wiggle from either (see pictures). It's definitely a bubba job, but what can I say? I don't regret the project or results, but the Bulgarian FSB route is probably the way to go.

 

20-20 hindsight, with the initial cost and the money I've sunk into modifications to my rifle, think I would have been better of going for a SGL21 straightaway, but live and learn... which I have.

[Klassy Kalashnikov 1,393]

Looks good. IMO the time and effort working on it is half the fun, I'd rather do my own work than own an SGL, but, to each his own. Your solution came out good, though you could have saved a bunch on shipping charges and wait time had you just bought the 24mm FSB.

[cobravenom39 17]

I don't understand how the brass rod is retained in the FSB? Thanks for sharing your ideas, MacGroober.

[Klassy Kalashnikov 1,393]

The brass rod is spring loaded which pushes it forward, however it is against the groove in the brake/adapter which keeps it from leaving the socket. On a standard brake, the pin is low enough so that the spring pushes it forward but the tip of the rod butts against the threads and remains captive.

[cobravenom39 17]

The brass rod is spring loaded which pushes it forward, however it is against the groove in the brake/adapter which keeps it from leaving the socket. On a standard brake, the pin is low enough so that the spring pushes it forward but the tip of the rod butts against the threads and remains captive.

 

I got it, so if the brake's removed it'll pop out.

Good job, though.

[modrisco 16]

The brass rod is spring loaded which pushes it forward, however it is against the groove in the brake/adapter which keeps it from leaving the socket. On a standard brake, the pin is low enough so that the spring pushes it forward but the tip of the rod butts against the threads and remains captive.

 

I got it, so if the brake's removed it'll pop out.

Good job, though.

It's exactly as Classy described. I played around with different combination's of brass rod length and spring length before I found a good balance, so the detent pin holds with the proper tension. It isn't retained with pins like a proper AK47 FSB, and it would pop out without attention if the MB were removed. I'm not too concerned about that at the moment.

[Klassy Kalashnikov 1,393]

I'm not too concerned about that at the moment.

 

Yeah I wouldn't worry about it at all if I were you, it's fine. If you ever did want to remove the brake you could just put a little piece of tape on the sight tower to hold the rod back or something. Or just let it pop out slowly.

[shades_of_grey 1,092]

...20-20 hindsight, with the initial cost and the money I've sunk into modifications to my rifle, think I would have been better of going for a SGL21 straightaway, but live and learn... which I have.

 

Yep.

 

Nice work, though.

[aekdbbop 5]

Quick question: when installing a muzzle device, should I just measure the threading on the inside of the device, then match that when removing the barrel shroud? What's the right procedure?