Using the following in my tactical i was able to get it to 39oz:
14lb Recoil Spring -0.3oz diff from Stock spring
10rd 11102 2.5oz
18rd Stock mag 2.7oz
Coco Bola 1.1oz
Rubber Stock grips 2.4oz
Starting weight with my stock SP-01 Tactical on a electronic Mail Scale is;
40.7oz with 18 round Mag
-0.3oz switching to 14lb spring
-0.2oz switching to 10rd 11102 mags
40.2oz
-1.3oz switching to COCO Bolo Grips
38.9oz is my weight now
Scale reads 39.0oz
Looks pretty good with the COCO BOLO grips, slightly thinner grip profile. Now need to get that trigger tuned. I like the trigger on my P07 , but it is going back to the Manufacture for some work.