I get a chuckle out of the knuckleheads who think that muzzle brakes are all about recoil reduction.
The big benefit in an intermediate calibres is that it reduces (virtually eliminates) muzzle flip allowing you to keep the rifle on target, and giving much faster follow up shots. There's a reason why the AR guys put on muzzle brakes, and it has nothing to do with recoil. It's all about keeping the barrel flat when popping off shots rapid fire on the same target.
I tested a few on a CZ-858 a while ago... Here's a splice of the results of the "rapid fire" test. The first 5 shot string is with no brake, the second with just a flash hider, the 3rd through 6th strings are with various brakes:
With no brake or just the flash hider, the gun isn't exactly pushing me around, but I do lose a moment between each trigger pull re-acquiring the target. With all four of the brakes, however, the barrel stays flat and on target, and I can pretty much shoot (and hit what I'm pointing at) as fast as I can pull the trigger.
As for the OP's question:
I've tried a couple of different brakes on the SKS, and they pretty much all sucked. They worked OK, while they stayed on, but they all worked loose eventually and became un-intended projectiles when they became mis-aligned and a bullet caught them and took them along for a ride.
Really, the only way to have an effective brake is to thread the barrel for one.
Cheers.
