Originally Posted by DocAitch
Its all been said above but to summarize.there will be little perceptible difference between the 2 bullet weights when you fire them
The 115 grainers are the standard NATO handgun bullets weight and some pistols may stabilize them better and be somewhat more accurate although that will be hard to appreciate with the Kel Tec's short barrel and fixed sights.
I believe that I have heard that the 124 grain bullet gained popularity as submachine gun fodder with the greater weight contributing to more reliable cycling.
NATO does not have a standard weight for the 9x19mm. Canada uses a 116 grain (they ALWAYS need to be different so they can claim theirs is superior, gets old after a while) and some European countries use 115.
M882 spec NATO ball, what the USA uses is 124 grain. At 1230fps, it has noticabley more recoil. Also CIP spec European ammo is loaded hoter to a standard than SAAMI +P will made to. Fiocchi "standard pressure" 124 grain XTP ammo you and I can buy steps out at 1290fps (no + or P on the box anywhere). 40fps faster than Corbons so called "+P" load of the mid 90s.
9mm ammo differences can be tricky sometimes...........