1377/1322 Full Length Breech

A custom, full length breech for the crosman 13xx series.  This provides a way to mount lights, LAMs, and red dots all along the same section of rail.

This uses ½-20 thread for the moderator mount, though I've included an M20 adapter I needed to mount my buckrail 1.5".  If using a thread adapter, a ½" washer is suggested to maintain perpendicularity.  You can also use the breech without any muzzle threads at all.

Four M3 x 4mm set screws clamp the barrel into the breech halves--making the two behave as one.  It took me a few iterations to get the clamping right to maintain accuracy and red dot zero.  It is important to install the front and rear breech halves completely before installing the set screws.