so your effective range is lot more like 50 yds than 500 yds. Our troops MISS the enemy completely with tens of THOUSANDS of rifle shots fired, and most hits are not solid, lethal type hits, either. So, it's like 50,000 rds fired (per really messed-up enemy.) Snipers hit MAYBE one man per day, while they are "afield", but they spend more time nice and safe on our bases somewhere than they spend in the 'hunting fields' of the enemy. the rifle accounts for less than 10% of the casulties on the battlefield, folks. Often, disease, accidents and "friendly" fire kills higher % of the enemy than do rifle hits. the beltfeds get about 10%, and the rest are caused by fire, falliing trees, buildings, and the great majority, by shrapnel type weapons, bombs, grenades, mortars, artillery, etc. The rifle is actually 'small potoatoes" as a military weapon. Also, many men cannot kill another man, by themselves, as a personal thing, especially not if the man is of their own race, at ranges where they can see the enemie's face. Most combat hits are random accidents, due to men firing at flashes in the dark, at movement, at buildings or vehicles where they know or suspect the enemy is. Many who do manage to kill, personally, suffer for it badly, with lost sleep, nightmares, etc, ,often for many years afterwords. Read MEN AGAINST FIRE", by General "Slam" Marshall (ww2) and ON KILLING (vietnam) by Dave Grossman. There's youtube videos about this, too.
That all depends which conflict you are looking at and even what branch of the service. During the Vietnam War, 38.1 % of all U.S. Marines who were killed was from (guns) small arms fire. http://www.marzone.com/7thMarines/usmc_cas_stats.pdf CASUALTIES BY CASUALTY CLASSIFICATION - "REASON" CODE __DESCRIPTION__________________ ENLIST OFF ALL %_ "D" GUN, SMALL ARMS FIRE 5425 227 5652 38.1 "G" OTHER EXPLOSIVE DEVICE 2935 122 3057 20.6 "E" ARTILLERY, ROCKET, MORTAR 2026 93 2119 14.3 "H" MULTIPLE FRAGMENTATION WOUNDS 977 30 1007 6.8 "B" AIR LOSS, CRASH - LAND 498 365 863 5.8 "I" MISADVENTURE 400 13 413 2.8 "U" OTHER ACCIDENT 372 10 382 2.6 "T" ACCIDENTAL HOMICIDE 307 5 312 2.1 "J" DROWNED, SUFFOCATED 188 7 195 1.3 "C" VEHICLE LOSS, CRASH 182 4 186 1.3 "A" AIR LOSS, CRASH - SEA 116 38 154 1.0 "R" ACCIDENTAL SELF-DESTRUCTION 129 3 132 0.9 "Z" UNKNOWN, NOT REPORTED 57 5 62 0.4 "V" OTHER CAUSES 57 4 61 0.4 "L" ILLNESS, DISEASE 55 2 57 0.4 "K" BURNS 53 1 54 0.4 "M" MALARIA 40 0 40 0.3 "O" HEART ATTACK 20 5 25 0.2 "Q" SUICIDE 21 2 23 0.2 "S" INTENTIONAL HOMICIDE 21 1 22 0.1 "F" BOMB EXPLOSION 11 0 11 0.1 "P" STROKE 5 0 5 0.0 "N" HEPATITIS 4 0 4 0.0 TOTAL CASUALTIES.......: 13899 937 14836