The M24 Sniper Weapon System (SWS) is the military and
police version of the Remington 700 rifle, M24 being the model name assigned by
the United States Army after adoption as their standard sniper rifle in 1988.
The M24 is referred to as a "weapons system" because it consists of
not only a rifle, but also a detachable telescopic sight and other accessories.
The M24 SWS had the "long-action" bolt version of
the Remington 700 receiver because it originally was to use the .30-06
Springfield M72 Match cartridge. Unfortunately it turned out there was an
insufficient amount of these rounds in a single lot of manufacture, so the
operational requirement changed to use the dimensionally smaller 7.62×51mm NATO
M118 Match Grade cartridge.[citation needed]
The M24 originally came tapped for the Leupold Ultra M3A
10×42mm fixed-power scope, which came with a circle-shaped mil-dot glass-etched
reticle. This was later replaced in 1998 by the cheaper Leupold Mk 4 LR/T M3
10×40mm first focal plane fixed-power scope with an elongated-shaped mil-dot
wire reticle.[2]
The first number is the scope's magnification (10) and the
second number in millimeters (40mm) is the diameter of the objective lens. A
fixed power scope has only one magnification (e.g., 10×) and a variable power
scope can be adjusted to focus between a range of magnifications (e.g., 3–9× is
adjustable from a minimum power of 3× to a maximum power of 9×). The rifle
itself comes with a detachable Harris 6-9" BRM-S swivel bipod unit.
The M24 SWS was to be replaced with the M110 Semi-Automatic
Sniper System, a contract awarded to Knight's Armament Company. However, the
Army still continued to acquire M24s from Remington until February 2010 and the
M24 is being upgraded to the A2 and M24E1 standard in many cases, and continues
to serve.[3] The Army is likely to upgrade its 2,500 M24s to XM2010 Enhanced
Sniper Rifle standard.[4]
Specifications
U.S. Army sniper team with the M24
SWS.
Sights:
Leupold Ultra
M3A 10×42mm fixed power, or Leupold Mk 4 LR/T M3 10×40mm fixed power scope. Detachable emergency Redfield-Palma
International back-up iron sights, fitted
with tabs that fit into slots machined into the front and back of the barrel.
Barrel:
Made of 416R Stainless Steel. The bore twist is 1-turn-in-11.25 inches
[1:285.75 mm] and the rifling is five radial lands and grooves (5-R) with
a right-hand (RH) twist. Because of the odd number of lands, none of the lands
are 180° apart, i.e. in direct opposition. This results in less bullet
deformation, which (at least in theory) produces more consistent point of
impact. In 5-R rifling, the "side" of the land is cut at a 65° angle,
rather than 90° in conventional rifling. This results in less barrel fouling,
and more consistent point of impact, compared to conventional rifling when
relatively high numbers of rounds are fired between cleaning, as might be
expected in military applications.
Stock:
H-S Precision PST-11 stock. The stock secures the barrel via an aluminum
bedding block to keep it rigid. A twin-strut extension that pulls out of the
butt is adjustable for a 2-inch [50.8mm] length-of-pull. This is effected by a
thick wheel on a central grooved pillar for adjusting the length and a thin
locking ring behind it locks the thick wheel in place. The latter is notorious
for failing, causing the extension to slide back and forth. Also a styrofoam
core designed to reduce the stock's weight would absorb water if it was carried
in the rain or soaked in a stream or river, making the weapon heavy and
unbalanced.
Accuracy:
According to MIL-R-71126(AR), the M24 shall achieve the accuracy results stated
below when using M118 Special Ball and fired from a Government approved machine
rest. The average mean radius shall be less than or equal to the following
values:[1]
- 200 yards (182.9 m): 1.3 inches
- 200 metres (218.7 yd): 1.4 inches
- 300 yards (274.3 m): 1.9 inches
Maximum effective range is given as
875 yards (800 meters), but record shots have been made with the M24 at over
1,000 meters (1,094 yd). Meanwhile, the standard optical sight has a
maximum elevation adjustment of 1,000 meters (1,094 yd).
Match-Grade
Ammunition
M24 sniper rifle, equipped with an
AN/PVS-10 Sniper Night Sight (SNS).[5]
- 7.62 × 51mm M118 Match Grade: A 173-grain round.
- 7.62 × 51mm M118LR Long Range: A 175-grain round using Sierra MatchKing Hollow Point Boat Tail projectiles.
- 7.62mm M118 Long Range Performance Data:
- Muzzle velocity (nominal): 2,580 f/s (786 m/s)
- Chamber pressure (typical): 52,000 psi (358.6 MPa)
- Action time (max): 4 ms
- Average horizontal spread at 1,000 meters: 10.3 in (0.984 MOA)
- Average vertical spread at 1,000 meters: 14 in (1.337 MOA)[6]
According to JBM Ballistics,[7] using the G7 ballistic coefficient
provided by Bryan Litz, the 7.62mm M118 Long Range 7.62×51mm NATO cartridge,
when fired at its nominal muzzle velocity of 786 m/s (2,580 ft/s),
should have approximately 878 m (960 yd) supersonic range under International
Standard Atmosphere conditions at sea level (air density ρ = 1.225 kg/m3).
- 7.62 × 51mm MK 316 MOD 0 Special Ball, Long Range: A 175-grain round consisting of Sierra MatchKing Hollow Point Boat Tail projectiles, Federal Cartridge Company match cartridge cases and Gold Medal Match primers and an undisclosed modified extruded propellant. The 7.62 × 51mm MK 316 MOD 0 Special Ball, Long Range cartridges have an accuracy requirement based around 10-round shotgroups. The Propellant has been verified as IMR 4064 (per NSN 1305-01-567-6944 and Federal Cartridge Company Contract/Order Number N0016408DJN28 and has a charge weight per the specs of 41.745 grains).
- The average extreme spread for 10-round shotgroups shall be less than or equal to the following values:
- 600 yd: 7.0 in (first Production Lot). This equates to a ≤ 1.1 MOA requirement at 548.6 m.
- 300 yd: 3.5 in (after first Production Lot). This equates to a ≤ 1.1 MOA requirement at 274.3 m.
The maximum muzzle velocity standard
deviation is set at 15 ft/s (4.57 m/s). Information published on
acceptance tests regarding five MK 316 MOD 0 cartridge production lots
indicated a sub 2.4 in at 300 yd performance. This equates to a sub 0.8 MOA
performance at 274.3 m for the listed ammunition lots.
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