IMHO:
The first one is excellent. I rarely like gun/knife photos because guns are very strong visual elements. They are scene-stealers. Furthermore, guns and knives usually don't have much in common. I hate the pictures you often see of a dull-black gun with black rubber grips photographed with this knife that has a bright silver blade and maybe some snakewood on the handle. The knife and gun have nothing in common. But, in your case, you have paired a knife and gun that look great together. They're a matching team. Perfect. You've also already learned about bleeding -- no not the knife kind of bleeding, the photographic bleeding where the knife goes off the edge of the picture. Some people don't like it. I think it's great. There is some object in the picture on the right-hand side, near the lower-right corner, looks like maybe a piece of wood or something. Is it in the picture or not? I find it distracting and I'd suggest getting rid of it.
As great as the first one is -- and it really is -- the others suffer a common, and photographically-fatal problem: to much stuff. It is very difficult to get more than about three things in a still-life picture (and these are what photographers call table-top studio still-life pictures) without it starting to look jumbled.
The third one (in addition to jumble) suffers the same problem that is the only problem in the first. There's something in the upper-left-hand corner that's distracting me. What is it? Is it in the picture or not? What's it doing there? I don't know. Just get rid of it.
Otherwise, your light is good and your color balance is good too.
Nice start.