Originally Posted by Gertz
I like the underwood ammo. I don't really like HP ammunition though. I like FMJ with a 9mm so I keep my tumble effect/penetration.
This is kind of a BS though. Whether the bullet tumbles or not is in the design, not the vel.
So all a faster FMJ gets you is it leaves the target sooner. Not much point in FMJ IMO, just poking less than caliber holes, UNLESS it hits bone or tumbles & there is just no guarantee either will happen. BTW, if the bullet does tumble, penetration is reduced drastically in any caliber. Damage goes up, but penetration goes down.
Reality, most RNFMJ will veer or deflect & not tumble & that comes at the end as the bullet slows. That loss of straight line penetration could mean a miss on vitals instead of a hit. The Gifford shooting is such an anectdotal event. A properly built JHP will straight line penetrate & cause a much larger perm wound channel leading to faster incapacitation. Think about it, one reason FMJ is banned for hunting in almost all states & is only prefered in Africa for thick skinned, large boned DG.
Yes, to each his own, but for most of us, FMJ is a handicap & you are already handicapped having to use a handgun for SD. Why make it worse, especially since your thought about penetration & tumbling are really counter to each other.