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Old 08-31-2014, 09:41 PM
PeterPocket PeterPocket is offline
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Originally Posted by Kanewpadle View Post
Anyone heard of this stuff? Saw a box of the 9MM today at the LGS. The 9MM was rated at 2000 FPS, 450 ft pds, and 12 inches of penetration!!

But I'll believe it when I see it.

Couldn't tell what the bullet composition was but it looked exactly like Corbon DPX but the bullet was silver colored. Not brass. Supposed to fragment along they way?!
On the Liberty Ammunition website, Liberty Lead Free Ammo - Liberty AmmunitionLiberty Ammunition | Global Leader in Lead-Free Ammunition, you can watch a 34 second video (shown at normal and super slo-mo speeds) demonstrating what happens when each one of their Civil Defense rounds is fired independently into the left side of a fresh block of ballistics gel by Joe Teti, billed as a 20 yr. Military and Special Ops Vet.

First of all, Liberty Civil Defense Ammo consists of a 50, 60, or 78 grain fragmenting bullet (not a frangible). The 50 grain bullet is actually fitted to four different caliber casings in the same product line. So, in addition to the 9mm, this 50 grain projectile sits on top of a .380, a .38 Special, and a .357 Magnum case.

The .40SW is toppedoff with a 60 grain bullet and the .45ACP gets the 78 grain "big bore." ;-)

The .45ACP is fired from a Colt 1911. Joe said he used a G23 in the .40 cal shot, which has a 4" barrel. I can't tell what fired the 9mm, but it looks like a baby Glock with a 3.46" barrel or maybe a G19 with a 4" barrel. That would explain the discrepancy between the muzzle energy shown in the video after the block was shot (>450FPE - which is also listed on their website). However, at the start of the video, it says 500FPE. That used to be the advertised amount. My guess is that a G17 with a 4.5" barrel was used to get the 500FPE number and a shorter barreled Glock was used to get the smaller number.

At least the .40SW is consistently listed at >500FPE.

I have also seen the kinetic muzzle energy of the 9mm listed at 533 FPE in a separate trial that was fired from a 5" barrel M&P PRO.

As we all know, the longer the barrel, the greater the muzzle velocity as the extra length allows the powder to burn and gasses to form more fully.

There are no videos for the .380 and .38 Special - which is probably a good thing since I can't figure out how a .380 and a .38 Special can both produce the same velocity and muzzle energy unless they deliberately skimped on the .38 Special's propellant.

A .380, aka .38 Browning Short, has a shorter casing for the same bullet as the .38 Special. So, why are they both rated at 1500fps and 250FPE? I know why they are both 250FPE - since its derived 's from the same equation of multiplying 50 grains (mass) times 1500fps*1500fps (velocity squared).

Yet, you would think with all that extra room in the .38 Special, the velocity would be higher - and in the real world of other +P ammunition, the most powerful brand of ammo across the entire self-defense spectrum, is the company called COR-BON: highly recommended by Massad Ayoob, the Godfather of Guns.

At this website, Ballistic Calculator GunData.org, you will find a ballistics calculator that will allow you to compare the velocities and muzzle energies from the barrel to the point on the ground across its entire trajectory. You can set the zero sighting point (which is set at a default of 100 yards w/ 50 yard increments, but you can change that to 25 yards with 10 yard increments). There are also a lot of useful links to be foundf at that site - such as what ammo to buy and what ammo to avoid like the plague.

I used the calculator to compare COR-BON's most powerful hollow-points in .380 (90 grain JHP) and their .38 Special (100 grain Pow'R Ball +P). I do not know what they use as their test gun, but I would guess it would be similar to what Liberty used.

To recap Liberty's figures, both the .380 and .38 Special leave the barrel at 1500fps with 250 foot pounds of kinetic energy. How does that stack up to COR-BON?

COR-BON's 90 grain .380 JHP had a muzzle velocity of 1050fps producing 220FPE.

COR-BON's 100 grain Pow'R Ball +P had a velocity of 1150fps producing 293FPE. So, COR-BON beats Liberty in terms of raw numbers.

And, these are both jacketed hollow-points.

And, that's where the big pitch fork shows up in the road because, unlike a mushrooming hollow-point, that fragmenting bullet is going to leave one very nasty wound cavity (or should I say "cavities") for the doctors to try and fix should the recipient survive the impact AND the additional depth of penetration from the solid core of the bullet.

For comparison sake, COR-BON's Pow'R Ball +P is normally the badass of the bunch in terms of energy as its 115 grain 9mm sibling has a flight path starting out at 1475fps with 488 FPE.

The question is, "Can these monsters be safely used on an "as-needed basis" in your SD when you know they don't recommend using +P ammo (and +P+ is a big no-no)?

It reminds me of the endless debate over whether a 5.56 NATO can be fired in a rifle chambered for .223.

The similarity hewre is that the SD9 and SD40 are chambered to SAAMI specs - just like the .223 Remington is - while the +P's, like Mil-Specs, have a tighter fit around the throat of the cartridge to handle the extra pressures generated by the Mil-Spec 5.56 rounds.

My guess is that the stove pipes caused by using the Liberty Ammunition is either due to the ammo's massive power, vis-a-vis a standard load, needed to push such a small amount of mass.

If a magazine filled with COR-BON Pow'R Ball +P's are tested out, and your gun survives with no ill effects, then, you can blame the ammunition.

Usually, stove pipes are caused by using weak ammunition that don't have the power to push the slide back far enough to properly cycle the ejector mechanism.

Maybe, in the case of too much power, the extractor gets blown past the point where it normally grabs the spent cartridge, or because of the tighter-fitting casing, the ejector has trouble freeing it from the chamber.

Either way, instead of pushing a new round into the chamber, the new round pushes on the back of the spent casing and up into that annoying vertical position.
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