Standard tall & short FSB's left, new deluxe tall right.

My front sight block deluxe models are now released. They have been redesigned to include a through window and captive index pin & spring. (used for indexing my AK-74 Brakes & Flash Hiders) They also allow use of my bayonet lugs and M9 bayonets.

These front sight blocks include a standard AK sight post, windage drum, indexing pin and spring as well as two set-screws and an allen wrench. Short one is designed to be used with the factory sights and the taller one is designed to work with my Press-On Upper Assembly with the AK rear sight block.

Left is the factory Russian FSB, it clamps on with a set screw at the rear. Middle shows both of my standard FSB's, one tall to be used with my adjustable AK rear sight system and one short to be used with the factory pistol sights. These attach just like the factory set screw model. Right is the new deluxe model with through window and captive index pin & spring.

Installation: Slip the FSB over the muzzle to just behind the threaded portion of the barrel. Screw on muzzle brake until tight, then back off so it is indexed in the desired position. Insert index spring and pin in FSB and push FSB forward so it is tight to the brake and the indexing pin engages the notch in the brake. Align the FSB with rear sight and gas block sight and tighten the set screws. If it looks nice & straight, remove one set screw, apply loctite and re-tighten. Remove the other set screw, apply loctite and retighten.

These pics show my FSB installed with the AK-74 Brake I offer. It's a scaled version of a real AK-74 brake and threaded for M20x0.75 RH threads.