SKU: 10LAMAG5300
UPC: 638457792850
MPN: GL10LAMAG-5-300
This is the factory 5-round magazine for the Great Lakes Firearms & Ammo GL10 long-action rifle chambered in .300 Winchester Magnum. It's a direct-fit feeding solution for shooters running the GL10 AR-10 platform who need a dependable magazine sized for the magnum case. The five-round capacity suits hunters working magazine-fed bolt-gun discipline on an AR-10 frame, as well as anyone in a jurisdiction with capacity limits. Built from billet aluminum with a black finish, it carries part number GL10LAMAG-5-300 and fits the long-action GL10 receiver specifically, not short-action or standard-length AR-10 magazines.
Construction is custom billet aluminum, machined for the longer overall length the .300 Winchester Magnum cartridge demands. The body measures 1.65 by 4.25 by 5.20 inches, which accounts for the extended magnum geometry compared with a .308-length AR-10 magazine. Capacity is five rounds, a count that balances the cartridge's length against a workable magazine height in the field. The black finish resists handling wear, and the aluminum body holds feed-lip geometry under repeated loading. Compatibility is specific: this magazine is engineered for GLFA long-action GL10 receivers only. Standard SR25-pattern or DPMS-pattern .308 magazines will not interchange, and short-action GL10 magazines won't seat a magnum-length round. Match the magazine to the long-action receiver and the feeding stays consistent.
Hunters chasing elk or other large game with a magnum-chambered AR-10 will get the most out of this magazine, as will shooters who need a compliant five-round option for restricted-capacity ranges or seasons. Keep a spare or two in the pack so a dropped magazine in the field doesn't end the hunt. If you run other long-action calibers on the GL10, the GL10 .30-06 magazine shares the same platform. Browse the full replacement magazine selection for additional .300 Win Mag options across other rifle systems.
It fits the Great Lakes Firearms & Ammo GL10 AR-10 style rifle chambered in .300 Winchester Magnum, long-action models only. It is not interchangeable with short-action GL10 magazines or with standard SR25-pattern and DPMS-pattern .308 magazines.
Five rounds of .300 Winchester Magnum. The five-round count balances the long magnum cartridge against a magazine height that stays manageable when shooting from field positions or a bench.
The body is custom billet aluminum with a black finish. The aluminum construction holds feed-lip geometry under repeated loading, and the finish resists handling wear during regular field use.
No. Standard .308-length AR-10 magazines are too short to hold a .300 Winchester Magnum cartridge at full overall length. The GL10 long-action requires this magnum-length magazine machined specifically for the longer cartridge.
It measures 1.65 by 4.25 by 5.20 inches per authoritative retailer specifications. The extended length accounts for the magnum cartridge geometry compared with a standard .308-length AR-10 magazine.
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