I have tested Montana X-Treme Bore Conditioner in I believe all my inlines and never experienced what would be 1000fps less on the first shot. What I do know is if you use too much it will seep into your breech and into your frame. A few drops is all it takes to treat the bore. A good thing to do after swabbing it out is to snap a few primers to clear it out of the plug but I have even forgot to do that and the first shot hit true.

Another product that will keep your first shot with #2 and #3 is Loc Ease Graphite lubricant. It actually dries fast and leaves a protective graphite film in the bore. I just dry swab it out before firing also.

This is the first I have ever heard of a claim of Montana X-Treme causing first shot fps to be extremely low. A lot of my first shots through the Chrony is me getting it positioned correctly. I just used Montana X-Treme in my smokeless 700ML and shots 1,3 and 4 were touching. Just my .02 cents though.