As has been said many times before this is just a game. While some reflection of the real weapon's character is desirable you can't model the performance of a gun like a .50 sniper rifle exactly as it might be in reality. It already has the unique ability to shoot through armoured glass and to deal severe damage to vehicles as a way to compensate for its loud report, slow action and fat reticles.
As far as realism goes I don't think people would want that.
Bullet-wound ballistics can actually vary widely depending on many things including range, bullet mass, bullet velocity, bullet type/shape, the angle of the shot, the size of the individual, where they're shot, clothing if any, the specific gun used (varied rotation) and whether the bullet strikes something on the way to the target. Many of these can combine to give irregular performance...
I've seen autopsy photographs of a guy's torso with something like 50 9mm Parabellum wounds in it (yes, you read that right). And these were police bullets so they're jacketed hollow points, not the less-wounding FMJ that militaries use. Not one of the rounds had performed as intended - didn't mushroom - so they punched neat little holes in this big guy's torso, all of which missed anything vital by sheer dumb luck/bad aim; apparently he was still standing before getting dropped by a shotgun slug that hit his upper spine.
At the other end of the spectrum some people just plain die of fright when shot, even if the wound isn't medically serious.
Then take two individuals with wounds to the chest that look superficially similar from .45 ACP - one a suicide, the other a gun-cleaning accident. Unfortunately the suicide missed anything vital and took hours to bleed to death, leaving him time to crawl to a phone and try to call for help; the poor dumb schmuck cleaning his gun died instantly.
So I think realism in a game would be highly overrated.