Hollow vs "not-hollow"?

[joeendris]

Ok, so I'm reading thru Federal's LEO ammunition papers and come across EFMJ rounds. Nifty little round, with a bit more ft/lb than say, a hydra-shok. What got me was the following:

It's the perfect choice for reliable expansion and penetration-not to mention for agencies that don't permit hollow point ammunition.

Are agencies really not allowed to use hollows? While not a fan, admittedly, of crash-n-bash tactics we see on TV, news, etc, I'm a little perplexed here. Ammo manufacturers, in this case Federal, have to design, test, implement a special round because for some strange reason, LEO's can't use hollow points? If these EFMJ rounds are better, slick, if not....well, I'm at a loss for words. My father piped up a few days ago about this as well. "Yeah, some of 'em can't use HP's...seems silly cuz it'll take a few more to drop the f**'er if he doesn't just get away". Ok, he was talking about the bad guy, but he has a point, and that's what piqued my curiosity about this.

Flame on, gang, maybe I'll learn something...maybe

 

[joshh]

the only reason i could assume a dept wouldnt want to allow hollow points is for better penetration? i know the fbi invested some time and money to determine a bonded-jacket hollow point (win pdx) would be the round of choice for them and many pd's have followed suit. from what i read the advantage of the bonded jacket is that it allows for expansion without separation. many hollow points experience separation or fragmenting when passing through barriers like doors, walls and even clothing. with these bonded rounds now available, i cant see why they wouldnt want to carry the hollow points but i am sure someone will be along shortly to explain...

 

[joeendris]

Penetration usually incorporates a deep impact zone, like a deer or a bear...definitely wanna stop Mr Grizzly if he's comin' at you . A person's center mass (or head) really isn't that expansive that, according to joe, one would need a penetrating round. I would think a round that frag'd (low penetration, full kinetic impact) would be the chosen round, especially at close range for a firearm.

 

[joshh]

Penetration usually incorporates a deep impact zone, like a deer or a bear...definitely wanna stop Mr Grizzly if he's comin' at you . A person's center mass (or head) really isn't that expansive that, according to joe, one would need a penetrating round. I would think a round that frag'd (low penetration, full kinetic impact) would be the chosen round, especially at close range for a firearm.

i agree. i cant see why they would want fmj as penetration is the only advantage to it. the only time you typically would want better penetration is when shooting through a light obstruction (like a windshield or door) which is why the feds liked the bonded jacket hp's. kind of a happy medium i suppose.

 

[GSG]

NYPD was using WWB 9mm FMJ ammo at the time Diallo was shot. Heck, the USSS was carrying reloads on duty when those guys tried to kill Harry Truman, because some number cruncher realized how much money they could save that way. Decisions aren't always made by the person with the most technical knowledge on the subject.

If someone higher up makes the call that no one's using hollowpoints, pepper spray, or whatever else it's not going to happen. There's still agencies that only issue a gun, cuffs and radio to cops. Some places lay down at the 1st complaint from a group of "concerned citizens" and throw their guys under the bus.

 

[bpm990d]

Mas Ayoob had some interesting information about the history of the use of hollow points for police agencies in one of his books. Before there was the assault weapon's ban and the gun show loophole there was the Saturday night special and dum dum bullet issue. I think that legacy still lingers in some places.

B

 

[In God We Trust]

The only LEOs that I know of using FMJ is the MP corps. Geneva convention rules I guess. Never heard of any civilians using FMJ, even the DoD / DOA guys use HP.

 

[rlee]

Do NJ LEOs use FMJ?

 

[ARV]

I think there is an exception to the law in NJ for LEO and IIRC that only applies when on duty(someone will correct me if that's not 100% accurate). Civilians are restricted to FMJ, so EFMJ would be good there and is what I would carry if in NJ, but seeing as I avoid NJ...

That reminds me of something a trucker told me yesterday. "You know the reason people in NY are so depressed? The light at the end of the tunnel...is New Jersey"

 

[ptanks56]

No ballistics expert, but EFMJ ammo seems to expand and create a large wound cavity, with out over penetration, plus it retains its jacket for reduction of fragments in wound area. They look like a Muther of a stopping round. Plus they look like they would not be slowed by heavy clothing even heavy leather.
Just by quick visual comparison looks like a 45acp 230grn would expand to diameter of maybe a quarter.

 

[whatluck]

EFMJ expands quite a bit, but expansion generally starts later than with JHP.

EFMJ has the ability to maintain trajectory through a barrier.

JHP will transfer more energy into a softer target.

EFMJ will transfer more energy into a harder target, or a target behind a barrier.

ETA:

Found this on ARFCOM: http://ammo.ar15.com/project/Self_Defense_Ammo_FAQ/index.htm

Some people like the Federal EFMJ since it's a "FMJ" design that is supposed to expand. While it does decrease feeding issues somewhat due to its shape, there's also a high failure rate in the neighborhood of 20% when it comes to reliable expansion. The other negative for this bullet is that it lacks sharp edges which slice though tissue and make a larger permanent cavity than a more rounded profile which tends to push tissue out of the way only to have it return to its original shape.

 

[joeendris]

No ballistics expert, but EFMJ ammo seems to expand and create a large wound cavity, with out over penetration, plus it retains its jacket for reduction of fragments in wound area. They look like a Muther of a stopping round. Plus they look like they would not be slowed by heavy clothing even heavy leather.
Just by quick visual comparison looks like a 45acp 230grn would expand to diameter of maybe a quarter.

That's a decent expansion.