The M82 is not without drawbacks however. It is very heavy and at almost 1.5 metres long it is quite unwieldy and difficult to carry over long distances. It is also not particularly accurate (around 2 MOA), due in part to its semi-automatic design and a lack of military match-grade ammunition, which contains many moving parts. Additionally it is simply overpowered for an anti-personnel role. For these reasons it is not considered a true sniper rifle, and is used in defensive positions where little movement is involved, against hard targets impervious to weaker weapons, and so on. In its intended niche the M82 remains extremely deadly.
The M82A1M variant has some differences to the original M82, such as a removable bipod and muzzle brake. The most obvious variation is the addition of a long Picatinny accessory rail on the top of the receiver that allows for a wide variety of scopes and sighting devices to be fitted. This variant has recently been accepted by the US military as the XM107 Long Range Sniper Rifle.
The M82A1M weighs 13.6 kilograms and has a 5 round detachable box magazine. The maximum effective range is 1000m for personnel and 1500m against materiel targets.