Shooting low and right

I am considering ordering a Drooper mount in 30mm from Mac1. I centered my scope per the instructions on the Mac1 website. I have a Talon SS, using the TriRail, and 2 piece high mounts. At 10 yds. I am shooting 3″ low (expected), and 4″ right 🙁 What could I try to correct the problem? I don’t want to remove barrel for maintenance, and end up with a shift in a different direction. Seems like it could be bushing alignment, or maybe uneven torque on the bushing set screws. How about the TriRail??? or maybe the scope mounts themselves. I’m using B-Square 25035 30mm, they seem to be pretty good quality, plenty of clamping screws. Is there anything I should do to try and correct the 4″ right error, or just let Mac1 take care of it?
TIA ~Terry