A couple of years ago, a Imgur user by the name of NSA_Listbot showed off one of the most impressive DIY creations ever attempted: an actual handheld, portable railgun. Its ability to fire plasma projectiles at speeds topping 550 mph was an incredible accomplishment. So, what’s the builder of the first handheld railgun do to top himself? Why, he makes it three times as powerful, shrinks it by half, and adds a semi-automatic firing mechanism, of course!

This is the SR-1, and it’s the first semi-automatic portable railgun ever built. It’s an incredible marriage of 3D-printed parts, high-end mechanical components, and truly brilliant design, and it’s already been used to kill melons and a laptop. Watch out, world.

In a series of new videos, the very talented builder shows off the new, smaller railgun firing a variety of different projectiles, ranging from titanium and iron to aluminum and even custom-made “plasma” rounds. The test firings take place both outside in a deserted area and inside what appears to be NSA_Listbot’s workshop.

The semi-automatic nature of the weapon allows it to be loaded with “clips” of ammunition rather than single shots, but there’s still a bit of a catch: the weapon’s charge time is significant, and before it can launch a projectile it needs to power back up, adding a delay between firings of roughly 10 seconds or so.

Even still, it’s obviously an extremely powerful weapon, and it’s amazing to see such a project progress through its various steps thanks to the detailed build album. The main question, however, is where does NSA_Listbot go from here? A faster-charging railgun? Even smaller size and more power? A fully automatic firing mechanism? There’s lots of possibilities here, and given his track record, I don’t think we’ve seen the last of this talented DIY-er.