Silenced weapons

[Breeze]

Hello all I have just picked up Arma 2 again after about a solid year away from it due to school. I remeber asking awhile back if there was any way to not have AI react to silenced weapon kills that were clearly not within their reach visually or hearing wise. I had gotten a reply that it might be in one of the upcoming patches.

So I am asking does anyone know if this has happened or if I need an addon any info at all?

Also I am trying to find Mr Murrays PDF file for mission editing

Thanks in advance
I have always loved the help you can get at this forum!!

[KeyCat]

I remember this was an issue long time ago in ArmA but not longer so in ArmA II 1.04 (and beyond) when I tested it with M9 SD.

/KC

[Breeze]

Ok so now Silenced weapons work the way they should excellent!!

[vinc3nt]

I have another silence related question that is kind of related:

What do SD (silenced rounds) do (ie. are the quieter, or only work in SD weapons).

[TKTom]

I have another silence related question that is kind of related:

What do SD (silenced rounds) do (ie. are the quieter, or only work in SD weapons).

Check the science behind weapon supression. The rounds labeled SD are subsonic, thus can be properly silenced. Normal rounds can merely have their muzzle flash suppressed, they will still crack even if the supressor was able to deal with all the gas out of the muzzle. In the vanilla ArmA2: OA I think that SD weapons won't take non-SD rounds, I'd like someone to point out if that isn't true.

And, about the main issue of the thread. I did a bit of a test the other day and it seems that the enemy will notice people in their squad dying pretty much instantly, but they won't pick up on members of other squads copping it or even receive contact reports from those squads. (That was over a 150m area in an urban environment.)

[Hunin]

Basicaly normal projectiles travel supersonic.
That means of course that - other then at extreme ranges - they impact before the target hears the shot.
The downside is that bullets create a mini sonic boom, often described as cracks or wizzes by those under fire.
So to conceal the sound of a weapon you have to both kill or dispense as much of the noise from the muzzle aswell as making the bullet fly subsonic to elimitate the cracks.
That's the special thing about "silent" rounds.
They simply travel at lower speeds due to less propellant.

Some weapons like the MP5SD family actually use normal bullets and slow the bullets down on their own by design of the barrel and fixed supressor, thats the exception to the rule though.

EDIT
lol Tom beat me to it.

[Ruges]

I shot the last guard in a patroling squad at 350m with a m17 sniper SD rifle. The other 4 or 5 people in the squad did not respond.

A thing to note here I was playing on the easiest difficulty. And if I shot a guard that anouther in that patrol was looking at then the patrol would respond. But still at 350m, they did not know who shot at them or where from.

[tyler4171]

But still at 350m, they did not know who shot at them or where from.

I did notice the AI's Ub3r spotting skills for snipers were decreased unless, you bracket your shots (fire more than one with in 3-6 seconds), the more you shoot the better they can find you...

[galzohar]

IRL and in Arma 2: Suppressors greatly reduce muzzle noise and flash.

IRL:Subsonic ammo is not required for the muzzle noise/flash to get greatly reduced, but they are required to eliminate supersonic crack that the bullet makes when it flies over the target.

In Arma 2: Subsonic ammo is required for suppressed weapons because of engine limitations. ACE works around that issue in a weird but successful way that doesn't require any extra effort from the user (other than loading the magazine you actually want to use).

Also, 5.56 normally flies at 800-1000 m/s depending on weapon, so reducing it to the speed of sound requires a significant loss of power and thus is rarely (if ever?) used in real life (and thus the Arma 2 suppressed 5.56 weapons are not very useful). 9mm, though, is fired from SMGs/handguns at much slower velocities and thus either very little muzzle velocity reduction is needed to reach the speed of sound and for some weapons no reduction is needed at all (but in-game you still need separate ammo because of the Arma 2 engine limitations). And as said, MP5SDs lose that small amount of velocity by letting some of the gases escape out of tiny holes in the barrel instead of using different ammunition. In fact I don't know if 9mmSD ammo even exists IRL, and it definitely doesn't get used in MP5s (this again was fixed by ACE).

[Panzer Jager]

What do SD (silenced rounds) do (ie. are the quieter, or only work in SD weapons).

Subsonic ammunition is usable in ArmA 2 even by guns that do not have supppressors. They do not produce a supersonic crack and AI cannot detect them as easily as normal ammunition.

In the game, there are some funny types of subsonic ammunition that wouldn't even be used by the Military - namely 5.56x45 and 7.62x51 subsonic ammo is not used to my knowledge. Subsonic 5.45x39 is used only in the AKS-74UB and 9x39 is used in a few weapons both suppressed and not.

What's interesting in ArmA 2 is that, considering that subsonic ammunition flies very slow, the subsonic bullets deal almost as much damage as non-subsonic. Their only real disadvantage is their reduced range and longer time before impact.

In fact I don't know if 9mmSD ammo even exists IRL, and it definitely doesn't get used in MP5s (this again was fixed by ACE).

There is subsonic 9mm ammunition. The bullets weigh 147 grains typically, compared to standard 9mm being in the 112-124 gr range. However, using 9mm subsonic in the MP5-SD is practically pointless as the suppressor will reduce it's velocity to near useless range.