lots,
no where shall i begin, lets start with basics, your barrel end is not square with the barrel, the same as the devices on the breech end, also all your mounting nuts need the same type of treatment.
may i suggest you play with basic geometrics, draw a tube, then turn it so you can see the end, now keep playing until the end is square with the tube, once you master this the rest is easy, look at photos and see the effect you get looking off square, then practice copying it.![]()