Algodoo

Very hard to load, I like it, reminds me of the Thomson contender

awsome

Things to work on:

* An ejector mechanism
* More stable rounds
* Better latch system

Notes:

Nifty design, especially the forward going bolt.
Like the trail coloring
Firing pin size seems a bit ridiculous

Ideas:

The bolt is really nifty, and you could make it work by a hammer very easily.
You have a lot of space, so you can make a smaller firing pin that can be hit by a Really lock hammer.
Get a spring, make a rail, and make it so that the hammer is released once the rail runs out. Let the trigger go, and the spring loaded "brick" could go back, and cock the hammer.