I had to re-zero yesterday after removing the barrel on my 17S to install the MI extended rail. After zeroing, I decided to see what the POI shift would be with my SDN-6. It shot about 6 inches low and three inches left in a nice tight group. Has anyone else experienced such a drastic shift with their SDN-6? I am wondering is I mounted the brakeout to the wrong torque specs. It did not seem to change the POI this drastically with 300 blk. Inspection of the can did not show any baffle strikes or other anomalies.