The revolutionary Windham RMCS-4 AR rifle allows you to switch between calibers with ease.Windham Weaponry's design is a massive leap in modularity for the popular AR-15. This rifle allows plenty of options for the survivalist or prepper in case one type of ammo becomes scarce or expensive, as the gun can shoot 5.56mm NATO/.223 Remington, .300 AAC Blackout, 7.62x39mm Soviet, or 9mm. Windham's brilliant engineers made switching out the barrel, magazine wells, and bolt/bolt carrier simple. Pick up this rifle and multi-caliber kit to see how smooth the transition can be.
The key to barrel interchangeability is on the underside of the MCS Upper Receiver. Once the Barrel Retaining Block is unlatched and moved forward, the Barrel Retaining Arms rotate out to release the barrel, ready to be replaced with the barrel of caliber choice. In the MCS Lower Receiver, magazine interchangeability is as easy as dropping the trigger guard and pushing in the Mag Release Button. One calibers mag well slides off, and another is substituted. Then, if required, the appropriate Bolt Carrier is inserted into the Upper, and with an appropriate magazine and the correct caliber ammo to match the barrel, the rifle is ready to fire. All WW barrels are clearly stamped with compatible caliber markings.
Visit our AR-15 Parts and Accessories section to further customize this AR-15 with the best selection of attachments and upgrades online.
Windham Weaponry RMCS-4 AR-15 Platform Rifle Features and Specifications:Platform Base: Complete MCS M4 Profile Rifle, Chambered in 5.56mm NATO with BCG capable of 5.56 mm NATO/.300 AAC Blackout)
Barrels: (4) Each 16", 4150 Chome Moly Vanadium Steel, Manganese Phosphate Finish
*Each Barrel Rifled Appropriately for Intended Caliber
- 5.56mm NATO/.223 Remington Barrel Assembly, Chrome-Lined Barrel
- .300 AAC Blackout Barrel Assembly, Chrome-Lined Barrel
- 7.62x39mm Soviet Barrel Assembly w/ Bolt Carrier, Chrome-Lined Barrel
- 9mm Barrel Assembly w/ Blowback Bolt Carrier, Melonite-Lined Barrel
Bolts: Machined from Carpenter 158 Steel
Muzzle Device: A2 Flash Hider
- AR-Type Magazine, 30 Rounds (5.56/.223/.300)
- AK-Type Magazine, 30 Rounds (7.62)
- Colt-Type Magazine, 20 Rounds (9mm)
- AR-Type Mag Well (.223/5.56/.300/7.62)
- AK-Type Mag Well (7.62)
- Colt-Type Mag Well (9mm)
Upper Receiver: MCS Flat Top with Integral Railed Free Float Forend, Hardcoat Anodized CNC-Machined Forged 7075 T6 Aircraft Aluminum
- Key to Barrel Interchangeability is on the Underside of the MCS Upper Receiver
Lower Receiver: MCS
Gas Block: Railed
Overall Finish: Matte Black
Heavy Duty Lockable Rifle Case w/ Custom Die-Cut Foam
NOTE: This item is oversized or heavy and is subject to a "Bulk Fee". The fee will be added to your cart at checkout.
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