Thanks for your comments @Allister_Caine!! Yeah, you're right about the pigment's application, I need to improve it so much.
About the contrast, in the table it doesn't look so agressive, as the light wich you take the photo with, increases this feeling.
Yes, I also need to improve those lenses... and give them a glossy varnish! ;)
Thanks again!!
the contrast is too strong in my opinion, but technically its fine!
try to do a sharper glare on the aiming-systems lenses... otherwise very good work, you can be better with the pigments, quite well used!