I had a chance to fire both the M-10 & M-11 back in the early 70t's. I was not impressed. The guns were unruly and had extremely hi cyclic rates. If I remember the M-10, 9mm version, was something over 1K @. This made the 30 round mag last about 2 seconds... Not what you'd call SUSTAINED FIRE..
Upside was the suppressor. Very quiet and the added weight allowed some control.
I also got a chance to shoot the M-11, .380 cal, "SPY" brief case. It consisted of the M-11 mounted in a standard American Tourister grey molded brief case. It had a button under the handle that acted as the trigger. A small panel on the forward edge was made of thin material and covered a "port". If you practiced, you could walk and fire one mag almost silently.
In 1973 we had two guys join C/3/20 SF(a) in Ft Lauderdale, under what you would now call the 18x program. Rolandito Masferrer and Anselmo Alliegro, Jr.
The Ingram was built for a while by an outfit named Defense Services, Inc., and marketed through an outfit called Parabellum. Rolandito was part owner of the company. He always had a couple in the trunk of his car and would set up demo's for the LEO's in the South Florida area.
If you follow Cuban politics, Kennedy's assassination, Anastasio Somoza, Mitchell WerBell, or any of an assorted cast of "black operators" from the 70t's, you might stumble across the names.
Interesting people...
The mustache is Rolandito,, in hi-speed gear...
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