Do FMJs gain any advantage from higher velocity? (pistol cartridges) [Archive] - Glock Talk

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Metal Angel
07-10-2012, 18:24
Is the 9mm NATO cartridge our troops carry any better than the 9mm mak Russians carry? Is 9mm mak fmj better than .380acp fmj? How about .357sig fmj? Is it better than 9mm NATO fmj?

Angry Fist
07-10-2012, 18:26
Different speeds should yield different penetration.

Berto
07-10-2012, 18:52
All things being equal, the faster one will be less likely to deflect from bone, will penetrate more and create more permanent cavity.

Andrewsky
07-10-2012, 18:57
Is the 9mm NATO cartridge our troops carry any better than the 9mm mak Russians carry? Is 9mm mak fmj better than .380acp fmj? How about .357sig fmj? Is it better than 9mm NATO fmj?

Higher energy will cause greater damage to the target.

Decguns
07-10-2012, 18:57
The USA's 9MM NATO & the 357 Sig both use .355" projectiles weighing 124/125 grains. The faster one would generate more energy, and thusly, penetrate further. In this case, the 357 Sig has about a 50fps edge in speed... with 465ft lbs for the NATO and 505 for the Sig. Sig should go further. Please note not everyone's 9MM NATO uses 124gr projectiles, nor do they load them to the same velocity.

The 380 & the 9MM MAK both like 95gr projectiles, but are of different diameters. The 380 being a standard 9mm at .355" and the MAK is .364". The MAK is about 100fps faster and comes in about 40ft lbs more. The larger diameter of the MAK projectile does seem to increase friction a tiny smidge over the 380 while passing through gel, but the MAK usually wins penetration. But at 237ft lbs, the MAK pales in comparason to the 9MM NATO and Sig.

gofastman
07-11-2012, 16:37
http://www.rathcoombe.net/sci-tech/ballistics/mechanics.html

Wounding is caused by the force exerted by a bullet to displace tissue. The exertion of force in displacing tissue requires an expenditure of energy, and translates into damage to the tissue in the form of penetration and cavitation as the elastic limits of the tissue are exceeded by the stresses imparted from this force. According to Cranz' Law, the kinetic energy of a non-deforming projectile is proportional (in a non-elastic medium) to the volume displaced by penetration and cavitation. But the quantity of kinetic energy alone does not tell us enough to predict the dimensions of this cavity. Reality differs. Real bullets generally deform and real tissue is extremely elastic. In understanding the interaction of the bullet with the target, it is helpful to consider the water analogy. The higher the impact velocity of a projectile, the greater the initial resistance. This is what I call the "splash effect", and is true of all solids when the stresses placed upon them overcome their intrinsic rigidity and cause them to behave like a fluid. It is easier to push your hand into water than to slap into it. Pushing slowly, you can penetrate deeper with less effort (energy) than by slapping at a high velocity. However, by slapping you make a bigger splash in the water (cavitation). These are exactly the basic mechanisms which govern terminal ballistics in living tissue. Understanding how the kinetic energy of a bullet contributes to wounding, we can consider the separate components of wounding.

esh325
07-11-2012, 17:39
Is the 9mm NATO cartridge our troops carry any better than the 9mm mak Russians carry? Is 9mm mak fmj better than .380acp fmj? How about .357sig fmj? Is it better than 9mm NATO fmj?
Not an expert, but I don't think there would be a huge difference between a 9mm MAK FMJ and 9mm NATO FMJ. The 9x18 will make a slightly bigger hole where the 9mm will penetrate more and make a slightly smaller hole. As far as whats better, the Russians are trying to adopt a 9x19 cartridge to replace their 9x18.

CAcop
07-11-2012, 22:26
The difference will be in penetration. Of course if a weak 9mm blows through something then a hot 9mm will blow through it even faster.