270 Winchester History and General Information.  The 270 Winchester is based on the more popular 30/06 cartridge case necked down to .277 caliber. Winchester began producing the .270 in 1923. Although the 270 winchester was in production in 1923 it was not officially announced until the introduction of their model 54 rifle chambered in their 270 cartridge in 1925.  The 270 winchester is a great dual purpose cartridge it can be used for varmints sending a 100 gr. bullet out the muzzle at a sizzling 3,500 fps. or it can be used as a big game cartridge sending 130 grain bullets out the muzzle at speeds of 3,100 fps. with sufficient power out to the 400 yard mark for deer sized game plus using 150 grain bullets at 2900 fps. it will flatten an elk out to about 250 yards.  The 270 winchester with the power it offers down range will recoil somewhat to the shooters shoulder with heavier bullets in the 150 grain range but is still quite tolerable to shoot.   270 Winchester Barrel Specifications. Common Barrel Twist Rate - 1/10 Bore Groove Diameter - .277"   270 Winchester Reloading Specifications. Bullet Diameter - .277" Maximum Case Length - 2.540" Trimmed Case Length - 2.530" Primer Size - Large Rifle   270 Winchester Loading Data Hints.  The 270 winchester responds well to i.m.r.powders such as 4064, 4350 and 3031 ignited by remington 9 1/2 primers in almost all bullet weights. 270 Winchester Reloading Data. Hodgdon Reloading Data Center. 270 Winchester Rifles. New Browning, Remington & Winchester, 270 Winchester rifles here.  Sponsor - Impact Guns. 270 Winchester Trajectory and Hunting Applications.  This is a down range trajectory chart for the 270 Winchester 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 .277" Bullet weight 130 grains Bullet ballistic coeffecient .392 Bullet velocity 3,100 feet per second Range 100 yds. 200 yds. 300 yds. 400 yds. 500 yds. + + 1.5 0 - 6.6 - 19.6 - 40.0 2341 1962 1635 1355 1118  Varmint + + + + + +  Deer + + + + - -  Elk + + - - - -  Moose + - - - - - Copyright 2001 - 2010