Anyone happen to know the standard length of the threaded portion of a barrel threaded at .5 diameter and 28 threads per inch? I'm having the barrel of my Bushmaster M17S shortened to a minimum and want to convert to a standard threaded length and the extra length used by Bushmaster. (Yes, I could say 'just thread it to standard', but I'm also doing this in CAD and am being picky about my little hobby drawing). I'm kinda hoping for something like this by the time I'm finished, although this doesn't reflect the Picatinny rails or M-Lock mounting points I'm putting in the drawing. The problem is that I am going to need to retain either a short section of the barrel shroud or cut the receiver to a bit longer than I want in order to meet the 26" OAL length, so I'm playing around with various configurations.