Zeebrahed
Member
I have recently aquired a HK USC that has been modified to use grease-gun mags. I pretty much love this gun, but I was wondering if I could get even closer to the style and look of a UMP. I know I must complete a Form 1 with all the pursuant paperwork to be able to chop the barrel but must I also file another Form 1 if I wanted to thread the barrel and add a supressor?