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Sniper bullets have unrealistically low aerodynamic drag
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The .408 Cheytac and 12.7x108mm APDS rounds have unrealistic airFriction values.

.408 CheyTac = -0.00013
12.7x108 APDS = -0.0001

Compared to real life, they are almost impossibly streamlined. Other low-drag bullets such as .338 Lapua or .50 BMG match rounds would have values of -0.0004 to -0.0008.

To match real-life ballistic data, the .408 Cheytac should have an airFriction of around -0.00042.

The 12.7x108mm APDS should have an airFriction somewhere in the range of -0.00030 -0.00035 to -0.00037 (or thereabouts, APDS data is hard to find).


Legacy ID
Steps To Reproduce

Inspect weapons and ammo config.

Event Timeline

Goose edited Steps To Reproduce. (Show Details)Jun 1 2013, 3:23 PM
Goose edited Additional Information. (Show Details)
Goose set Category to Config.
Goose set Reproducibility to Always.
Goose set Severity to Feature.
Goose set Resolution to Fixed.
Goose set Legacy ID to 3420637571.May 7 2016, 2:23 PM
Bohemia added a subscriber: zGuba.Jun 1 2013, 3:23 PM
zGuba added a comment.Jun 1 2013, 3:31 PM

I've applied the drag for APDS and SLAP rounds config. It's invaluable, thanks!

However this source:

States the .408 has really low BC. I tried to match the air friction so bullet shot with init speed of 930 m/s keeps supersonic up to 2200 meters.

Goose added a subscriber: Goose.May 7 2016, 2:23 PM
Goose added a comment.Jun 2 2013, 1:11 AM

Hmmm, when I use airFriction = -0.00042 (or thereabouts) with initSpeed 930, the bullet still appears to be supersonic at more than 2,200 meters (calculated ArmA velocity of *about* 366 m/s at 2,200 meters).

The initSpeed in the current config is 910 m/s, it is also supersonic @ 2,200 meters with that muzzle velocity.

zGuba added a comment.Jun 2 2013, 1:35 AM

Going to review .408 once again. Thanks for input!

Scoggs added a subscriber: Scoggs.May 7 2016, 2:23 PM
Scoggs added a comment.Jun 2 2013, 9:24 PM

While this is over my head, still upvoted because I want realistic ballistics!

Thanks for the hard work!

pettka added a comment.Jun 5 2013, 9:09 PM

I have added an explanation on forums (see - this has been done for gameplay sake and there is just a slight chance we would be able to fix that for release of the game, because it would break the game balance otherwise.

There have been improvements in this way on engine side that made real values usable in game. Could you, please, confirm the fix and close the issue?

Goose added a comment.Jun 27 2013, 2:57 AM

Checked, airFriction values have now been set to appropriate values (26/06/2013). Good work!