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CarreraGT
07-09-2005, 16:59
I've seen reference made here, and over at SOCNET, about current ammunition being available that will defeat the current standards. As someone pursuing a career in Law Enforcement, I am curious as to just how much of it is really out there. I've examined the entire NIJ Standard 0101.04 Manual, and am trying to figure out just how to interpret it.

For example, level IIA lists:
40S&W, nominal weight of 180gr, minimum impact velocity of 1025f/s or less.

What is better/worse than that? Some are simple; Speer's 180gr Gold Dot mirrors that velocity from the muzzle, and generates 420 lb/ft of KE. Double Tap's 180gr moves at 1140f/s, obviously defeating a Level IIA vest (from the muzzle of course).

But what happens when you start shaving weight and up-ing the velocity? What about more weight and less velocity? What is the factor associated with the Threat Level Standard? KE? Velocity? I'm assuming the answer is "all of the above". The NIJ Standards also specify a FMJ... not a JHP...

I keep RBCD's 70gr 40S&W TPD in my house gun (Glock 22). Only 70gr, but at 2320+ fps and 790+ lb/ft. This would appear to surpass the IIA Standard by FAR, and most likely even the IIIA?

Can someone make sense of it all???? :eek: :confused:


Dave

Peregrino
07-09-2005, 18:07
A lot of ammunition will defeat the current standards. The NIJ only uses certain rounds with calibre, bullet type, muzzle velocity, barrel length, etc. specified to test the ballistic materials. They try to ensure that those "standard" rounds are representative of what is available on the street, but they can't and don't test everything. If the ballistic material resists the test rounds, it gets certified for that level. The test criterion should be permanently affixed to the exterior of the ballistic panels. If you get shot with a bullet that was not included in the tests, all bets are off. The test results can give an idea of what other, similar rounds the ballistic panels will resist but the factors that affect penetration are too varied to cover every possibility. Simply firing a tested round out of a carbine (not always tested) or using a different bullet shape even when weight and velocity match test ammunition may give it the muzzle velocity (and energy) to defeat armor that passed when previously tested within the standards. Spend the money you think your life is worth and buy the best vest you can afford. Of course you could buy two identical vests, wear one, and shoot/test the other with the questionable ammo. If it resists penetration all you need to do is hope the vest you're wearing doesn't have any hidden manufacturing defects. :D FWIW - Peregrino

longrange1947
07-31-2005, 23:36
One of the things that must be remembered is that all vests can be defeated and all ammo can be defeated. Problem is you must wear to defeat what is being carried by the majority of your "target audience". If that is only a lower level then wear that and wear it everyday. If you wear what will defeat even high velocity stuff then you will not wear the vest everyday. It is on the day you do no wear it, some punk will msoke you with a .22 cal derringer made of pot metal. Another day you may wear the defeat the world vest and possibly some guy will smoke you with a .50 Raufoss round.

But you have to ask yourself, what vest will I wear everyday and what is my most common threat. It sure as hell is not that Raufoss round. Go withthe IIa and be secure in the thought that you will live to see your grandkids get married. :)

whit
08-21-2005, 10:05
"Simply firing a tested round out of a carbine (not always tested) or using a different bullet shape even when weight and velocity match test ammunition may give it the muzzle velocity (and energy) to defeat armor that passed when previously tested within the standards. Spend the money you think your life is worth and buy the best vest you can afford."

Perigrino's advice is sound. NIJ is useful, but only as a general guideline.
You are WAY too light with a 70-gr. pill at any velocity. Perhaps particularly at very high velocity. What happens when the Bad Guy has on a heavy wool coat, and the shot happens to catch it in a fold? It will hurt him, but does not give adequite penetration to make him terminally ill (see Miami shootout-FBI). We were issued Glock 22's in .40, so we "learned to love it". ;^)
Carried 180 gr. subsonics loaded with Gold dots because in my job I also had a can for the gun, mainly for canine and light supression. If you want a bit more energy, go to 165's or even 155's but keep in mind that *any* pistol calibre ctg. has marginal "stopping power". Placement, Placement, Placement. I personally would not go below 155's in a Forty for the above reason, and I like the 180's because they ensure adequite penetration.

Situational Awareness is usually more important than what type vest you have on. This to include location of the nearest cover and manouvering wrt the
suspects to keep it handy! Unfortunately, as a cop, you most often have to
move in and arrest the turkeys; you can't just shoot 'em. This is where
things usually get dicey. Best you can do is pay attention/learn good weapon retention, SPEAR (a *very* useful tool for the cop), cuffing techniques and general
arrest techniques such as an agreed-upon silent signal to your partner that
an arrest is imminent. Good Luck.
whit