The 5.7x28mm creates incredible KE when fired from the PS90 (even more KE than the P90 due to velocity increase that results from longer barrel length). Penetration isn't an issue with the 5.7x28mm round and the result is an average of 80 joules of energy, which is lethal.
Isn't an issue? Penetration is THE issue with the 5.7, even in SS190 trim... As far as the lethality of the round, countless law enforcement agencies have dropped the weapon system after it has proven ineffective. Everyone wanted this weapon system to live up to all the hype the FN junkies created, but it simply lacks substance. Fired out of either weapon system in any of the commercial or LEO-only loads, the 5.7 lacks the penetration and expansion of standard subgun calibers and lacks the energy of a full blow 5.56 or other rifle caliber... Simply put, it was a really cool looking, really hyped failure.
I've followed quite a few of your posts, ministerofdeath, and you absolutely have your terminal ballistic "priorities" bass-ackwards. Energy is great, but ONLY when it compliments adequate penetration. Energy scores a DISTANT second to penetration when ranking performance of defensive ammunition.
I'm not saying this weapon system has no application - if a small PDW with the ability to lay down crazy suppressive fire is required, the P90 fits the bill (and god knows it beats out HK's failed 4.7mm ). In the hands of very skilled operaters (as is the case with the Secret Service), the quality of shooter is going to make up for the weapon system's shortcomings... But at the end of the day, trying to liken the 5.7x28mm to a viable replacement for the 9mm-.45ACP, .223, or any other "real" caliber is a losing proposition - the numbers simply do not add up.
And what a tangent we have taken this thread on... We started out talking about the MSAR and stumbled into the dark, chimeric world of FN and now onto discussion about a cartridge that no MSAR has (or will be) chambered in... A new thread would probably be prudent if you guys wish to discuss all this business in further detail... :beer:
Hold up there, sunshine... I didn't "personally insult" you - I said you thought process is wrong. You give velocity too much credit...
Originally Posted by ministerofdeath
That's more than enough KE to achieve adequate penetration. That is after all all they were after with the 5.7x28mm enough penetration to kill, but not so much that it over penetrates.
That isn't how it works, ESPECIALLY with small, light projectiles. When you start juping up small hunks of metal to blaze through the air at incredible speeds and then smash them into fluid environments, they come apart. This is why you can't take any old 115gr. 9mm, load it up to +P+ pressures, and expect it to hold together long enough to out-penetrate a much slower 147gr., etc. We see the same thing happening with 5.56 in various loads (not just the M193/M855 that are designed to fragment)...
I think that calling the PS90 a "failure" is open to question. The gun with the SS190 did exactly what it was designed to do. It provided a PDW for behind the lines support that could defeat Russian body armor. That "D" in "PDW" stands for defense, and that was the purpose of the weapon. It was never intended to be an offensive weapon.
My understanding is that the gun got caught up in a lot of NATO politics and the need for the gun fell with the Wall. The reputation of the SS190 got hyped and politicized and the controversy began. The watered down civilian rounds pulls most of the teeth from the PS90, but I think it is useful to remember that the 5.7 round is only in its infancy and that the limited ammo availablity, controlled by FN, is a temporary situation, especially with reloading. For me the jury is still out.
I have to laugh about the 5.7. Depending on who is arguing it can be everything from a mankiller to a plinker, or an over-penetrator or one that will not penetrate enough. Some say that it tumbles, others that it yaws, and ballistic tests seem to get ignored. While I'm not convinced one way or the other, it seems to me that the two available rounds offers a basis a good bit shy of that necessary of coming to anywhere near a final verdict. Of course the government may end up stepping in and settling that for us once and for all, and at that point the PS90 will go from controversial to legendary.
To me the bottom line is that folks are arguing about a gun that is no longer being used for its intended purpose and judging it on a basis that has little overlap with reality. The 5.7 may well develop into a round that will bring the PS90 gun more uses, but for now it's more of a novelty.
Then again, take a Beretta CX4 in 9mm, or an HK94 (both semi-auto 9mm carbines, the round the 5.7 was to replace) and then add in a PS90. Say you have to take out an opponent at 200 yards. Chose your weapon.
try .355 147gr round nose/JHP or boattail with velocity of 1100fps
also try .355 90gr any bullet type with velocity of 1500fps
9mm can send 147gr bullet 1100fps with 4" barrel could do it faster with +p loads
90gr 1500 fps short bullet so limited to COL can probably send it faster without increasing barrel length.
what would you rather count on a 28.5/40gr bullet or something 2 to 3 times that.
its much like a 5.56 vs 7.62x51 or 223rem vs 308win
sure you can shoot 5.56/223 rem 1000 yards its not going to be anywhere near as effective as 308win which can use bullets 2x-3x heavier.
penetration is one thing critical damage that doesnt close back up is another.
I dont totally agree with what syntax and Buzz have said but I believe they are along the lines of reality of the effectiveness of 5.7x28mm otherwise we would see the cartridge take off.
try looking up the cartridge .224BOZ another is 224VOB
5.7x28mm color me unimpressed. its not a good defensive round it was designed to penetrate armor.
niche cartridge for limited uses.
it comes down to shot placement for rounds like 5.7x28mm and 223remington.
And that's exactly it, at 200 yards, or 150, or 100 for that matter, I'd rather have the PS90 than a 9mm carbine because of the ability to achieve that shot placement and quick follow-up shots back on target with a minimum of muzzle rise. The gun in the right hands could be devastating even with the toothless civie rounds. Add to that the 50 round capacity, and the gun is potentially more effective than other carbines that get a lot more respect.
The gun is all about shot placement and the ability to put multiple rounds on target very quickly and accurately.
Yeah, politics have arguably neutered the round but we're really only a couple years out and I think it remains to be seen what can be and will be done with reloaded rounds.
The biggest (and probably most obvious) problem with the 5.7x28mm is that it is a small projectile moving at relatively low velocities. Primary cavity size will not lend much to causing incapacitation from blood loss and we're certainly not moving fast enough for hydrostatic shock to contribute much to the wound characteristics (in FiveseveN, P90, OR PS90 trim).
I thought add some words from a few people who probably are more qualified to talk about this subject than most of us...
Dr. Gary Roberts had this to say about the 5.7x28mm & P90 weapon system:
Originally Posted by Dr. Gary Roberts
I have shot the P90 and I have analyzed the wound channels. The terminal effects are substandard. I'd personally rather use an MP5 PDW, a Mk18, or even a .30 caliber carbine. The ergonomics on the P90 are also not particularly wonderful.
Other than being able to perforate soft body armor, the 5.7 x 28 mm used in the FN P90 causes wounds less incapacitating than those made by 9 mm FMJ fired from a pistol.
I have personally fired the 5.7 x 28 mm FN P-90; velocity, penetration, and tissue destruction is like a .17 Hornet--far less than we see with 75/77 gr OTM out of our Mk18's. Winchester RA45T 230 gr JHP’s fired from our duty 1911’s crush more tissue and penetrate further than the 5.7 x 28 mm.
Several papers have described the incredibly poor terminal performance of projectiles fired by the FN P90:
--Dahlstrom D, Powley K, and Gordon C: “Wound Profile of the FN Cartridge (SS 190) Fired from the FN P90 Submachine Gun". Wound Ballistic Review. 4(3):21-26; Spring 2000.
--Fackler M: "Errors & Omissions", Wound Ballistic Review. 1(1):46; Winter 1991.
--Fackler M: "More on the Bizarre Fabrique National P-90", Wound Ballistic Review. 3(1):44-45; 1997.
--FBI Academy Firearms Training Unit. FBI Handgun Ammunition Tests 1989-1995. Quantico, U.S. Department of Justice--Federal Bureau of Investigation.
--Hayes C: “Personal Defense Weapons—Answer in Search of a Question”, Wound Ballistic Review. 5(1):30-36; Spring 2001.
--Roberts G: “Preliminary Evaluation of the Terminal Performance of the 5.7 x 28 mm 23 Grain FMJ Bullet Fired by the New FN P-90 , Using 10% Ordnance Gelatin as a Tissue Simulant”, AFTE Journal. 30(2):326-329, Spring 1998.
--Roberts G and Lazzarini D: “Terminal Performance of the 5.7 x 28 mm 31 Grain SS-190 FMJ Bullet Fired by the FN P-90 in 10% Ordnance Gelatin.”, AFTE Journal. 34(3):302-303, Summer 2002.
The current 5.7 x 28 mm 31 gr SS-190 FMJ bullet has nearly adequate penetration, but the wound resulting from this projectile has a relatively small permanent crush cavity, as well as an insignificant temporary stretch cavity. Although the 5.7 x 28 mm penetrates soft body armor, wounding potential is at best like a .22 LR or .22 Magnum. Even 9mm NATO FMJ makes a larger wound--and we are all aware of the awe inspiring incapacitation potential of M882 ball from the M9......
It is all basic physics and physiology. Look at the surface areas in contact with tissue for 9 mm FMJ and JHP compared to 5.7 mm. When both are point forward, the 9 mm FMJ crushes more tissue than the 5.7 mm; for the short time that the 5.7 mm is at FULL yaw, it crushes a bit more tissue than the 9 mm FMJ. At no time does the 5.7 mm crush more tissue than the expanded 9 mm JHP--even when the 5.7 mm FMJ is at full yaw, an expanded 9 mm JHP crushes more tissue. The relatively small temporary cavities produced by both the 9 mm and 5.7 mm projectiles are not likely to cause significant injury to the majority of elastic structures of the body. As with any penetrating projectile, if either a 9 mm or 5.7 mm bullet is ideally placed to cause significant damage to the CNS or major cardiovascular organs, a fatal result is likely.
The P90 can definitely penetrate soft body armor, but then so can 9 mm AP rounds. The greater momentum of 9 mm bullets allow them to defeat vehicles and other intermediate barriers better than the 5.7 mm bullets. Standard 9 mm, .40 S&W, and .45 ACP JHP loads crush more tissue, offer ideal penetration, and are equally likely to not exit the opponent as the 5.7 mm. 5.56 mm and 6.8 mm weapons offer significantly superior terminal effects compared to 5.7 mm.
Bottom line—what does the P90 offer that is not already available? The best uses for the P90 might be for executive protection details where the threat is expected to be wearing body armor and perhaps as a PDW for vehicle crew and pilots.
As Buzz mentioned, this round has inspired an incredible amount of debate. Purely speculative, but one has to wonder why FN hasn't pursued any 3rd party testing to settle the debate... any guesses why?
A member of Jacksonville SWAT posted up over on lightfighter awhile back and had this to say about the 5.7:
When I first saw the cartridge I had my doubts about its efficacy. When I first saw the P90's magazine arrangement I had my doubts about its reliability. When the first series of tests came in it confirmed my previous fears about its performance.
...And then after having the chance to train with a group of people who have more operational experience with the P90 than any other LE entity in the United States and who have been in MULTIPLE firefights with the P90 and seeing them give the weapon a big thumbs down because the bad guys were saying "Stop that!" when you shoot them with it....
Well....I formed a less than favorable opinion about the weapon and the 5.7 cartridge.
As a toy, it is a fairly neat (though very expensive) one. As a tactical tool, there are much better options out there.
Renouned instructor Pat Rogers of E.A.G. Tactical had this to say:
Originally Posted by Pat Rogers
Both Houston TX and Jacksonville FL used P90's. I am not aware if Houston still uses it, but having spoken at length with a J'ville SWAT cop who was involved in multiple shootings with it he had this to say.
"The gun is accurate and controlable. That is a good thing because you need to be able to hit the BG with a lot of rounds- they have little effect. The magazines crack and if we had it to do again, we wouldn't have bought them".
If the 5.7 does one thing well, it is outperform the 4.6... As mentioned before - these are niche calibers and weapon systems primarily designed to defeat body armor and to be wielded by very capable shooters... CCW and home defense are certainly not what either platform was intended for and that is why there is a plethora of better choices available to us... :wink: