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Firearms

The Hydra MARCK-15 H21, the Latest Version of Hydra’s Modular Rifle

November 16, 2024 by Fred Rowlands 2 Comments

Hydra Weaponry, Maine’s top gunmaker and the brains behind the MARCK-15 Hydra® Weapon System knows how to cater to the Glock crowd. Their latest creation? A modular rifle built around the .45 ACP, the second most popular caliber in civilian, law enforcement, and military circles (right behind 9mm). Enter the Hydra MARCK-15 H21 Modular Rifle—a powerhouse designed for shooters who want to get the most out of their Glock and dive into the world of modular rifles.

The MARCK-15 With H21 Conversion Kit

The folks at Hydra didn’t mess around. They engineered a .45 ACP H21 mag well and paired it with their Hydra Quick Change Barrel Upper Receiver (QCB-D). Toss in a 16-inch blowback barrel, a blowback bolt, and a rock-solid B5 Systems stock and pistol grip, and you’ve got a rifle ready to perform.

Glock .45 Mag Well

Here’s where it gets fun: This rifle is your gateway to a whole new caliber-swapping world. Thanks to Hydra’s growing lineup of mag wells and conversion kits, you can switch calibers without breaking a sweat. No tools are needed—just swap out the mag well, barrel, bolt, and carrier in the field, and you’re good to go.  Other calibers using Glock mag wells include .40 S&W, 9mm, and 10mm.

“A modular rifle is a game-changer when you’re trying to stretch your budget but need versatility for different missions. That’s why our Hydra MARCK-15 rifles offer unmatched quality and accuracy without draining your wallet. Now’s the perfect time to snag a base model and stock up on conversion kits during our sale!” says Mack Gwinn III, CEO of Hydra Weaponry.

The MARCK-15 H21 in .45 ACP tips the scales at 10 pounds and measures 21” x 3” x 7”. It has a sleek black finish with MLOK, KeyMOD, and Picatinny handguard options. Price tag? A cool $1,399.00 but retail sales bring the price down and once you buy a full rifle, you only have to buy a conversion kit next time.

The Perfect Stocking Stuffer, Honest!

About Hydra Weaponry

Based in Maine, Hydra Weaponry packs five decades of firearms innovation. From the Bushmaster pistol and rifle to their cutting-edge modular platforms, the Gwinn family has set the bar high. The MARCK-15 Hydra is the culmination of their mission to deliver modularity, durability, and pinpoint accuracy for operators working in the harshest environments. Hydra Weaponry: redefining the future of small arms.

Garfield Out

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About the Author

Fred Rowlands Fred “Garfield” Rowlands is a 21+ year Navy veteran who spent his career in strange and diverse places like Diego Garcia, Wintering Over in Antarctica, the Southern Border, and Burbank CA. Has spent over 30 years working in Military Physical Security, Law Enforcement, and Private Security, and has “more luck than a cat has lives” supposedly. He now resides in NW Florida with his wife and a Great Dane named Layla.

See All Fred Rowlands Articles

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