I've seen a trend here recently, towards the heavier 9mm sub-sonic hp's. Just some f.y.i. for all you 9mm owners out there who are trusting your lives to this.....don't do it. The 9mm 147 gr. hp's were originally developed by our government for "eliminating" sentry dogs in vietnam, from silenced pistols of course. By adding mass, the round never breaks the speed of sound, thus no report,thus easier to silence. This "wonder round" was very short lived, due to its in-effectiveness. The 9mm has only one thing going for it, decent muzzle velocity in the 115-124 gr. range. When you rob it of it's velocity, it doesn't possess enough mass(such as the .45 acp), to make up for it. Reliable expansion is also very "iffy" at sub-sonic velocity, which equals an in-ability to transfer it's muzzle energy reliably to the target. The 147's came back for a very short time again in the late 80's, and again it was immediately discarded.I am not a 9mm advocate, but if you trust your life(lives) to this caliber, this info may be worthy of some consideration.