Spent most of the day shooting the HK UMP 40 with a AAC Defender.
This particular UMP a semi/two round/full-auto trigger pack.
Gun is standard HK UMP fare. I installed a vertical foregrip and rail kit from AAC
just for a little more control. About the only thing that was different with this UMP and the 9mm and .45 ACP versions was the cyclic rate was a little faster. The two round burst option is very nice but with proper trigger control I could get two and three round bursts on full auto.
The AAC Defender
suppressor works VERY well. In tests it achieved -30 db of sound reduction. An added benefit with the AAC is that it's a dry suppressor and can sustain full- auto fire.