300 Winchester Magnum History and General Information.  The 300 Winchester Magnum was developed by winchester based off of their own .338 win.mag. by moving the shoulder area of the cartridge forward .156" and lengthening the case .120", winchester introduced their 300 to the public in 1963.  The 300 winchester magnum has enough power, using 180 grain bullets to drop deer well beyond 600 yards and it will take elk at 500 yards.  The 300 winchester magnum is one of the few cartridges that really make the case for free boring and a longer action, with bullets seated deeply in the cartridge case it's full potential can not be realized by the limited case capacity of deep seated bullets.  note: (see rifle gunsmithing free bore)  The 300 winchester magnum when loaded with 180 grain bullets recoil is quite substantial but is still controllable, a good recoil pad fitted to the rifle is a must have.   300 Winchester Magnum Barrel Specifications. Common Barrel Twist Rate - 1/10 Bore Groove Diameter - .307"   300 Winchester Magnum Reloading Specifications. Bullet Diameter - .308" Maximum Case Length - 2.620" Trimmed Case Length - 2.610" Primer Size - Large Rifle   300 Winchester Magnum Loading Data Hints.  The 300 Winchester Magnum when loaded with hornady 180 grain bullets backed with a charge of i.m.r. 4350 or 4831 powder delivers superior accuracy and packs a lot of game stopping power for anything in all of north american hunting. 300 Winchester Magnum Reloading Data. Hodgdon Reloading Data Center.   300 Winchester Magnum Trajectory and Hunting Applications.  This is a down range trajectory chart for the 300 Winchester Magnum cartridge with the scope mounted 1.5 inches above the bore center line plus if you were using this load, its effective hunting bullet energy range with well placed shots on, Varmint / Predator size game, such as Bobcat, Cougar, Coyote. Deer size game, such as Antelope, Blacktail, Hogs, Javelina, Mule, Whitetail. Elk size game, such as Caribou, Black Bear, Sheep. Moose size game, such as Brown Bear. Bullet diameter .308" Bullet weight 180 grains Bullet ballistic coeffecient .482 Bullet velocity 3,100 feet per second Range 100 yds. 200 yds. 300 yds. 400 yds. 500 yds. + + 1.4 0 - 6.4 - 18.5 - 37.3 3348 2904 2509 2160 1853  Varmint + + + + + +  Deer + + + + + +  Elk + + + + + -  Moose + + + + - - Copyright 2001 - 2010