Chain gun: Effective engagement ranges?

[Hummingbird]

Here's a question for the AH64 experts out there:

 

What is the normal/effective engagement range of the chain gun as used on the Apache? 

 

Most guncam footage I've seen seems to show engagements around 1500-2000* (meters ?) usually. Is this the usual engagement range with the gun? Is it ever used further away than that?

 

Note: For reference the Ka-50's gun in DCS seems usable out to about 4 km it seems, but it's also higher velocity. Hence I was wondering what to expect in regards to the Apache.

Edited July 13, 2021 by Hummingbird

[1stBEAST]

effective engagement range against what?

i think in general the ranges mentioned above are pretty accurate for effective fire. the gun itself isnt as accurate as the ka-50 gun and wasnt meant to be in all books it is described as area weapon.

[AlphaOneSix]

4500m

[FoxTwo]

23 minutes ago, AlphaOneSix said:

4500m

 

I believe that's max range, I've seen 1500-2000 for effective on armor.

[Lurker]

This is a 30mm weapon right? So that would make it pretty effective against lightly armored and soft targets. On par with the Mi24P's cannon, but it should be much more accurate if fired from a hover because of the HMD aiming system? 

[1stBEAST]

meh* i think it will be more in-accurate in a hover because the canonen pushes the heli around. if its moving forward and fireing forward ist should be more accurate.

if you are orbiting and shooting to either side there is also quite some "kentucky windage" needed. and the gun has also quite some dispersion if its shot at ranges above 1.2 miles if i remember correctly what i was told by an apache pilot at the ILA in Berlin.

[Lurker]

A rate of fire of 600rounds per minute is nothing to scoff at, but it's designed to be fired in short bursts AFAIK. An effective range of 1500m is more than enough for this type of weapon. As for the recoil effect at hover, well I don't know about that, but the entire Apache design philosophy was to make it an incredibly stable weapons delivery platform, in all regimes of flight including hover so I doubt that it would be more inaccurate in a hover, but I'll let someone more knowledgeable answer that one. 

[kseremak]

Seems like more accurate aiming system than Mi-24P cannon, but bigger cannon bullet dispersion.

[DaemonPhobos]

Maximum effective range is 1500-1700 meters per gunnery handbook

Maximum ballistic compensation up to 4200 meters, beyond that you get  BAL LIMIT performance inhibits.

Typical gun engagements according to most TADS videos are at between 700 to 1000 meters.

The round to round dispersion of the M230 is around 3 milliradians by the book, however, that does not appear to be correct per real life videos, probably that's the nominal dispersion of the gun itself not taking into account the flexible turret and other factors.

Edited July 15, 2021 by DaemonPhobos

[S. Low]

Regardless, I really hope they get the frag damage implemented otherwise the 30mike won’t quite be what it’s supposed to be. 

[Hummingbird]

9 hours ago, S. Low said:

Regardless, I really hope they get the frag damage implemented otherwise the 30mike won’t quite be what it’s supposed to be. 

 

Indeed, there needs to be an vicinity effect vs infantry and very light skinned vehicles.

[Hammer1-1]

IIRC its deliberately made to be a large spread burst because its a payload ammunition for the most part. Dont expect to snipe with it, and dont expect to hit everything you aim at; just everything else around it. A few things Ive heard is that its like this because theres no really simple way to negate the recoil of that rifle on a rotating turret.

[DaemonPhobos]

You are not supposed to aim directly at the target, but slightly offset and short of the target.

The M789 HEDP has a butterfly shaped frag pattern with a 4 meter lethality radius in a diagonal shape (forward-left/ forward-right are the areas with most fragmentation.)

The gun is called Area weapon system for a reason, it's not meant to be pinpoint accurate.

[Lurker]

Should still be accurate enough to mop up trucks and other unarmored, or lightly armored targets. Unfortunately I don't think it will be effective against infantry in DCS, as currently HE fragmentation damage is not modeled in DCS. Anything other than a direct hit will probably be completely ineffective against infantry. 

Edited July 14, 2021 by Lurker

[1stBEAST]

hey, if the gun does not quite kill infantry there is also the possibility of a "warhead on forehead" solution with a hellfire

[Krez]

On 7/13/2021 at 7:38 AM, Lurker said:

This is a 30mm weapon right? So that would make it pretty effective against lightly armored and soft targets. On par with the Mi24P's cannon, but it should be much more accurate if fired from a hover because of the HMD aiming system? 

The GSh-30-2K cannon on the Mi-24P is a modified version of the GSh-30-2 on the SU-25. The M230 Chain gun will not tank out a tank like the GSh-30 will.

[Curly]

This is from 1995, I dont know if the accuracy has been increased since then. https://apps.dtic.mil/sti/pdfs/ADA299307.pdf

[jubuttib]

On 7/13/2021 at 3:38 PM, Lurker said:

This is a 30mm weapon right? So that would make it pretty effective against lightly armored and soft targets. On par with the Mi24P's cannon, but it should be much more accurate if fired from a hover because of the HMD aiming system? 

It is 30mm diameter, yes, but the shell is MUCH shorter, and isn't necked down. I.e. the powder load is very different. The Apache uses the 30x113mm cartridge, where the Hind uses the 30x165mm (same cartridge as used by the Su-25T), which is more comparable to the 30x173mm round used by the GAU-8 in the A-10 in terms of energy. Not sure if effectiveness is as good, since there's more to these kinds of rounds than just bullet size and powder load, materials etc. also play a big part.

 

Some comparison images:

 

Apache, Hind and A-10 cartridges labeled in the image. Some of them look a bit off (might not be milspec), but this gives you an idea. The following pics don't have all three, but are probably more like the actual rounds used by the aircrafts in question:

GAU-8 uses #1, Apache uses #3. You can clearly see how big the difference in powder load is going to be. If you'll allow me to exaggerate slightly, it's a bit like comparing a .30 caliber pistol round with a .30 caliber rifle round. EDIT: Btw, some people were clamoring after the turreted version of the Hind, I think that peashooter would have used the #10 12.7x108mm rounds. Comparing #10 to #1 (which is close to the 30x165mm in the Hind), I'm happy we didn't go that way.

 

GAU-8 cartridge on the left, GSh-30-2 cartridge on the right. Those two are much more comparable than the cartridge used by the M230 on the Apache.

 

Edited August 17, 2021 by jubuttib

[jubuttib]

On 7/16/2021 at 10:59 PM, Curly said:

This is from 1995, I dont know if the accuracy has been increased since then. https://apps.dtic.mil/sti/pdfs/ADA299307.pdf

 

That's... That's a lot more spray and pray than I was expecting. =/

 

Though checking for the muzzle velocity it does start to make sense, it's only a bit higher than on an AK-47 (with of course a longer, heavier, likely ballistically better projectile), combine that with a turret mount and a hovering platform, and it makes sense. GAU-8 is fixed and has about 25% higher muzzle velocity, so it's no wonder that it could be specced to "80% of rounds fired at 4,000 feet (1,200 m) range hit within a 40-foot (12 m) diameter circle"

[MRTX]

From what i've seen on Apache guntapes, their grouping of the gun is normally about 10-15 meters big at about 1.0 to 1.8 kilometers, so that estimate seems pretty accurate. And in the end software can only do so much until your guns physical accuracy limit is reached, so i don't really expect any severe accuracy improvements in the future, and although accuracy can always be better I'm pretty sure that the DOD and especially the pilots are satisfied with it. And since bell and sikorsky have both shown their FARA concepts with rotary cannons I'm expecting that the armys future platforms will have comparable if not even worse gun accuracy.

[Lurker]

This now begs the question how effective the gun is going to be within DCS World?

 

Will the HE (High Explosive) shells be modelled in the game? I.E. You fire a H.E. 30mm round burst for a near miss on a squad of infantry out in the open. Will these shells explode on impact incapacitating or possibly even killing the enemy squad, like they would in real life, or will they be harmless near misses? 

Edited August 23, 2021 by Lurker

[S. Low]

The 30mm (or whatever it is) on the blackshark is quite effective even without the frag damage. I’m pretty sure it’ll kill infantry (HE selected) and it takes out light vehicles at 4km using area damage. In that regard it’s a lot of fun and reminds me of the Apache gun.

 

I didn’t realize it at first but the hind’s gun only has AP ammo currently, making it miss our expectations. Though I think it wouldn’t be so bad having an AP cannon if the HE rockets weren’t so completely terrible. 
 

If the blackshark’s gun can be used as a reference point for the Apache gun then I wouldn’t worry about it. I’m sure it’ll be fun.

 

And yes those videos online show Apache 30mm with a 15 meter spread but that’s at like 3000m distance and fired from an angle. That’s a really good balance between AOE for infantry/moving targets/groups but precision enough to hit where you need it. I wouldn’t worry about that aspect either.

 

Lazing for fast movers is going to be where it’s at anyways

[MRTX]

I've tested the current DCS M230 with HEDP ammo, and it has really good HE performance and it also shreds anything up to a BMP into pieces. Only weird thing is that ED gave the HEDP ammo a 11 second timed fuze. But nevertheless it was never meant for player use, and they're probably going to rework it although what we have right now is suprisingly good.

[fargo007]

The Ka-50's cannon is nothing to sneeze at in terms of capability.

 

People who know have remarked that the modeling of the KA-50's gun is very similar to the Apache in many respects.

 

If we get that, I think it shakes out as both realistic, and DCS-useful.

 

[Lurker]

Coolbeans. I haven't flown the Blackshark since it was a standalone game. Thanks for the replies.