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4.
A long range sniper rifle that is preferred by the Navy Seals. It can often be mistaken for a .30-6, though the two weapons are radically different.
With this M40A1, I can shoot you in the crotch from 800 meters.
by Detranova July 29, 2003
 
1.
A modern 7.62x51 Nato bolt-action sniper rifle used by the Marine Corps.
"The hapless Taliban group was pinned down behind a rock, trapped out in the open. We had them. Two of their buddies lay dead. Their AK's were useless. One of them made the mistake of peeking out from the rock. He lifted his head up again. I saw his eyes through the Unertl's 10x scope. It looked as if they met mine, even though he couldn't see where we were. Then.."
by JM October 23, 2003
 
2.
The M0A1 is the USMC's Scout Sniper Rifle. Based on the Remington 700's action the rifle is hand assembled by the Corp's highly trained expert armorers. It is equiped with an Unertl 10x scope specially contracted by the Marines. The rifle maintains one minute of angle(MOA), in other words it holds a one inch group at 100 yards, 2 inch group at 200 yards, etc... In the hands of an experienced marksman it is accurate up to 1000yards (915meters)
Carlos Hathcock smoke the Vietkong with his M40A1.
by Gun Nuttz November 08, 2003
 
3.
The weapon widely regarded as the "Ultimate Sniper Rifle". Basically, it's a modified Remington 700 rifle. Introduced late in the Vietnam War.
"That's an M-40A1 dude."
by Chris G. October 23, 2004