Hmmm, how about the delayed blowback setup with a 5-8" barrel with with a true comp and running slow powders (AC,HS6 ect) around 150PF. I wonder if the comp would work enough or would you have to run it up to major power to get the benefits of the comp like a open gun. Although you would not get major scoring. I like the idea of the delayed blowback for this as it would lessen the worry about a out of battery event.