M11/9mm Slowfire Conversion
M11/9mm Slowfire Conversion
The
whole idea behind the "TASK" slowfire conversion is to replace the function
of the captured recoil spring on the bolt assembly with the spring and
buffer system of the M16. This replacement increases the weight attached
to the bolt, thereby decreasing the cyclic rate of fire.
The first
task that needs to be completed is fabrication of the stock adapter.
I found some 1/4X2" strap at ACE that is suitable for the base of the adapter,
and some 1/8X1/2" strap that is suitable for the rails. For the threaded
mounting region of the AR 15 stock, a CAR15 locking nut (~4$) works well,
and doesn't require you cutting a funky thread on a lathe.
Cut a
rectangle piece of the strap, .625"X 1.5" (you can adjust this to your
liking). Cut two notches in the bottom corners to accept the rails
(the rails are .312" tall and 1/8" thick). Drill a centred 1/2" hole
1" up from the bottom.
The 1/2" rail material needs to be milled to 0.312" - this must be done on a mill. Cut a 0.375" wide slot 0.10" deep, use the photo below for clarification. This notch is the stock catch, and muct be 0.920" from the end of the rail in order to correctly engage the latch. Once all completed, the piece needs to be TIG welded together (MIG will work). I used my M11 as a "JIG" and it works well, just pay attention to not burn through, or you'll not be happy with the results. Locate the CAR ring as low as possible, see below.***
Next, remove the roll pin located on the end of the recoil rod, slide off the bolt off - remove the spring. Remove the firing pin and grind it as the picture below indicates:
You now need to tap the hole in the rear of the bolt. The best pitch to use is1/4-20. Make sure you lube the piece well, do not try to free hand this! Use a drill press, keep pressure on the work, use a carbide tap, and GO SLOWLY. Back the tap out frequently to clear the shavings. The bolt is REALLY hard.
Now the scary part... drilling your receiver. Drill a 5/16" hole 1.189" from the top of the sight blade, and centred (my centred measurement was 0.6475", so 0.648" or 0.647" - take your pick).
***Below you can see what the final product looks like. The stock ring may be welded after you complete the rest of the project, position of the op rod helps with alignment. If the op rod rubs or drags on anything, file to fit. You will find that changeing buffers, springs etc will dramatically change your ROF.
