First of all. Don't do this.
Cutting off the front removes a ridge that is needed for the chain to feed properly. Thankfully I only made this mistake once, and as long as good shells are on either side of it in the chain, this shell still feeds and fires properly.
Now on to actual modding. Here we have one of those tricky bastards.
If you look very closely at the base you'll see a small ridge where there is a cap glued into place on the inside of the shell. Start by making a small cut along that ridge.
It only needs to be deep enough to give you something to dig into. Now insert the point of a knife into that cut and using very light pressure work the knife in.
Remember LIGHT pressure. When the plastic gives it will give suddenly. I have a stab wound on my left hand to prove it. Just work at it gradually until your knife slides in. I'd really advise using a smaller knife than the one I'm using. This is pretty dangerous.
Once the knife is in start sliding it around the edge to cut the cap off. You don't need to make a straight cut, in fact you'll probably slip and go from cutting under the ridge to over it. that's not a bad thing, in fact it will probably make things faster, and help you line the cap up when you're putting it back.
Behold. Ye olde guts. Look how much dead space that AR created, almost an inch. With that cockblocking bastard out of the way, you can get your darts further in, use steffans, or streamlines. Yours will look slightly different from mine if you're going from stock shells. I drilled out the pegs earlier.
Now you can cut the entire peg off down to the base. I'd aslo advise carving that hole out wider. (also done previously), and you should have this nice clean cap with nothing sticking out.
Now measure out some CPVC or barrel material of choice, put some hot glue around the end that will face the front of the shell. and pus it as far in as it will go. The glue around the front should be thick so it can smear around the inside and fill in to make a better seal.
Lastly put a ring of glue around the back of the pipe and pop the cap back on, push down hard to get it all the way down, remove any extra glue, smooth out the edges and you're done.
Now just do it 29 more times and you have a full chain. I'd advise setting up an assembly line process to make it quicker. Cutting out all your barrels ahead of time will make things much easier.
And there you have it. Go shoot some zombies.
