Yes I think that is true, but exactly how much I don't know. I'm fortunate to own a .40 caliber MK9K. Dr. Dater said that Gemtech made somewhere between six and eight of them. When I bought it used it was set up as a thread mount for a MP5-40. I had the end cap changed to one with a 3-lug mount. Because the thread mount threads onto a Navy style barrel, the can might be somewhere around 1/4"-1/2" shorter OAL using the thread mount instead of the 3-lug. Now if your application was on a plain threaded barrel without a 3-lug, you might get the OAL an inch shorter.Guys if I go the thread route won't the overall length be shorter than If I went the 3 lug route? At least that's what I recall reading on here??