The Remington Model R-25 is semi-automatic

Semi-automatic rifle

A semi-automatic rifle is a type of rifle that fires a single bullet each time the trigger is pulled, automatically ejects the spent cartridge, chambers a fresh cartridge from its magazine, and is immediately ready to fire another shot...

 gas operated rifle that comes in three different calibers such as: .308 Winchester

.308 Winchester

The .308 Winchester is a rifle cartridge and is the commercial cartridge upon which the military 7.62x51mm NATO centerfire cartridge is based. The .308 Winchester was introduced in 1952, two years prior to the NATO adoption of the 7.62x51mm NATO T65...

, .243 Winchester

.243 Winchester

The .243 Winchester is a popular sporting rifle cartridge. Initially designed as a varmint round, it is now more frequently used on medium to large game such as whitetail deer, mule deer, pronghorn, wild hogs, and even black bear and caribou...

, and 7mm-08. All three calibers are based after the .308 Winchester cartridge. The Remington R-25 has a 20 inch Chrom-Moly medium fluted barrel and free floating handguard. Overall weight without optics is 7.75 pounds. The R-25 is based on the Armalite

ArmaLite

ArmaLite is the name of a small arms engineering facility founded in the early 1950s, and once associated with the Fairchild Engine and Airplane Corporation. ArmaLite was formally incorporated as a subdivision of Fairchild on October 1, 1954...

 AR-10

AR-10

The AR-10 is an American 7.62 mm battle rifle developed by Eugene Stoner in the late 1950s at ArmaLite, then a division of the Fairchild Aircraft Corporation...

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