Will a short prochamber match with BBK LT's

Not without some modification. I have BBK LT's and use to have MAC LT's with the shorty O/R Prochamber. I asked the same over on Modular Depot, and one guy had done it. Said you have to widen the ends, he banged them a bit until they fit, on each end. I did not want to risk any leaks and opted to just go with the BBK O/R H. So yes it can be done, but its not a direct fit, you have to bang it around and widen each end.