sounds like fun
you can go as far forward as the back side of the vert air hole (where the air comes up from the lowertube) if there is an oring on the bolt, i wouldnt go past it...
custom pump handle, delrin works great for handles, metal would be better for the hitman, too much torque on delrin threads and it could break/pull out
cram and jam
sanchez makes a 12rd feedtube that drops directly into the existing feedneck, if you want it to screw into the ion feedneck threading.... its alot more work
Ryan “Super_Stanchy” Stanchfield