I have a g21 with a storm lake barrel, so that I may shoot lead bullets. I cast my own bullets and shoot a 250 grain bullet. I have a stainless steel guide rod in which I entend to exchange the 17lb recooil spring for a 20lb recoil spring. So that I may reduce muzzle flip, to get back on target quicker. I shoot in bowling pin competitions so quickness/speed of target aquasition is very important. I shoot the 250 grain bullet, to knock the bowling pin completely off the table. My question is will a 20lb spring reduce the muzzle flip. In another post I was told to try a 15 lb spring. That line of thought does not make sense to me a 20lb spring would seem to reduce muzzle flip instead of the 15lb spring.