I don’t have a sense for the explosive power of the 30 mm high explosive incendiary round used by, say, the chain gun in an Apache chopper or the A10 Warthog’s Avenger gattling gun (I’m not even sure the rounds are the same for both platforms).
Would such a round explode with the power of a typical infantry soldier’s grenade? Less? More? By how much?
Phrasing my question another way, if the round exploded ‘x’ meters away from me*, what, if any value of ‘x’ would lead to my death, and what value of ‘x’ would cause me “serious injury” (whatever that means)?
*yes, I know that it’s a contact detonation in IRL
Your question piqued my interest as well, so I went hunting.
And came back empty. I can find lots of data on the M230 and GAU-8 gun systems, and even some decent ballistics specs on their available rounds, and tons of data on the various platforms they are all mounted on, but nothing on anything like burst radii or kill zones for specific types of explosive rounds.
Best I could locate was a 5m kill zone/15m wound zone of the M67 Hand Grenade on Wiki.
I don’t have any definite answer to this question, but after some googling I found that the PGU-13/b (High Explosive Incendiary) round’s projectile for the A10’s GAU-8 weighs about 360 grams, while for example a M/67 handgrenade weighs about 400 grams. That doesn’t necessarily say anything about the lethality and range though, but it gives an idea of what might be plausible. I didn’t find any information about how much high explosive each of them pack. The lethal range would depend both on the amount of explosives in each, as well as how it fragments. I am not qualified to make any estimate though.
As a WAG I would say that they are of a similar magnitude in lethality.
I didn’t find the projectile weight of the M799 HEI round for the Apache gun, but I think it’s smaller than the PGU-13/b.
One obvious difference is the amount of HE rounds from a chain gun as opposed to a single hand grenade. The Apache can fire an amazing number of rounds in a very short timeframe, so there’s lots of overkill. I’m not certain if it’s even possible for an Apache’s chain gun to fire a single round in order to compare to a single hand grenade.
Also…would the velocity make a difference on the distance of the “kill radius”? A grenade thrown by a soldier is travelling at a far lesser speed than a similarly charged bit of ordinance from an Apache’s gun.
Sheess… A chain gun that can basically fire hand grenades. I never thought about that before.
I wonder how it compares to the 40mm that can be mounted under the stock of a rifle? I always thought those would be a lot less damaging than a hand grenade, other than it would have a great deal more range or reach.
There’s plenty of Apache gun camera videos available on the Internet, just google Apache gun camera or the like. (I’m not linking directly to videos because some may not like to clink on a link to see videos of people being killed.)
Suffice it to say that while very powerful, one can see that the 30mm doesn’t have the effect area of a hand grenade. There are videos out there of a cannon shooting a good amount of rounds into the area of bad guys and fairly often there are some who survive the first salvo.
As far as a “hand grenade chain gun,” this is somewhat up your alley.
As a WAG, given the two items are close in weight, I’d go with the grenade as being a little more deadly. Mostly because the grenade is presumably optimised for deadliness, whereas the cannon round also has to be able to survive being shot out of a cannon, so therefore needs stronger walls, etc.
And then the extra velocity of the cannon round would make a less lethal explosion. Assuming the person isn’t hit directly, then the cannon round is going to dig into the dirt or wall of the house or whatever it does hit, and that’s going to contain the explosion a little bit. The grenade will be sitting on top of the ground, or most lethally be in mid-air, when it explodes.
“I’m not even sure the rounds are the same for both platforms).”
They arent.
After a bit of googling, the AH64 uses the M230 chain gun which uses a 30113mm round, while the Thunderbolt 2 uses the GAU-8 Avenger, with a 30173round.
Not sure what that would mean from an HEI perspective, but AP wise, they’d be pretty different Id think.
The kill radius is a function of the explosive filler charge inside the 30mm round, causing the round to fragment in a manner similar to a grenade.
There may be some “geometry” issues with the fragmentation spread due to the angle-of-impact, much the same way with an artillery round.
The only factor the velocity of the round is going to have is with a kinetic impact, assuming that perhaps “soft targets” (people) may not have sufficient “hardness” to detonate the explodey bit of the 30mm HEI round.
If they do, it’s just wrong on so many levels.
“First, we shoot you with a Big Damned Bullet. While it’s inside you turning you inside-out, it explodes.”