Range Report (M&P FSS follow up)

Just a quick, yet well overdue follow up to my last range report.  I finally had a chance to shoot the Apex poly-FSS equipped M&P 9L on paper.  After a few warm up shots, I shot this group free hand (beware of cr@ppy cell phone pic):

10 shot group at 10 yards with M&P 9L w/ Apex polymer FSS trigger kit using Federal 115 gr FMJ RN

The orange spot is a 1 1/2″ target spot with the group being about the width of my thumb with slight vertical stringing.  I’m pretty sure the stringing is my fault as I adjusted my grip while shooting this group; the fact that it is off center I attribute to the rear sight placement.  In order to change out the factory sear block for the Apex one, the rear sight must be moved out of the way*.  Obviously I did not restore it to the exact same spot.

Time for some math.  Or I could just use Brownells sight correction calculator

• Distance between front and rear sight faces: 7.25″
• Distance to target: 360″
• Amount of correction desired: 1″ (to the left)

Therefore, I need to move the rear sight:  0.020 inches to the left

Now where did I put my caliper?

As for the trigger, I’m still very happy.  Of note is that I originally reported the pull weight at 4 lbs 10 oz, but using the Lyman digital trigger pull scale borrowed from a range employee I measured it again at 5 lbs even.  I’m not sure which scale is more accurate but I am careful to keep my technique consistent.  Out of curiosity, I will swap the carry weight trigger spring for the competition weight spring before my next range trip to see how much difference it makes in pull weight and subjective feel.

Either way the trigger feel is fantastic and my personal metric of ‘do I shoot it better after the mod?’ tells me that this was definitely a worthwhile upgrade and it made the M&P’s easier for me to shoot accurately.

FTC notice: TANSTAAFL. I bought it. Bugg3r off.

*some might consider this a design flaw, although it may very well be to avoid a patent infringement. ,:/