Although the outlook is pretty decent, the semi-auto shooting performance is not as smooth as in your video. I have checked the tutorial several times, and I think the issue is that the rubber bands are not very effective during shooting. Even after making several adjustments, it still doesn’t work as a semi-auto pistol.

This thing looks amazing and the mechanism works way better than expected. The only caveat to this is that I found it to be rather fragile. Some super glue is recommended in the instructions, but I had to use a lot more just to keep it from falling apart from slight movements or using the bolt. Other than that, it is an amazing display piece and, with careful handling, really fun to try and shoot targets with. Genuinely impressive work of Lego engineering

All pieces rcved, took few hours to build on one sitting, haven't gone so lego-tistic since 2009 when building my Lego Star Destroyer. Smoked a cigarette afterwards since the build was THAT good.