Originally Posted by BigOldSkool
To explain the angled rail..... Thompson foregrips aren't flat on the bottom.
Any one can make a square pump.. now angle it and match the rail to that angle so the whole thing is paralleled to each other and while your at it drill the mounting holes into the bottom angle.
Maybe off topic, but uh, if you ever get the chance to shoot a Thompson M1A1 DO IT! They are so choice....
Nice mods man, if you're looking for something other than flip-up sights then a good red dot is the way to go, magnification is kind of useless.