The Magpul does fit the Adams Arms perfectly. The Adams Arms is very high quality and is boringly reliable. I have two friends that both have the same rifle as you and have thousands of rounds through them with not a single malfunction. I personally like the Adams Arms piston system much better than the LWRC and other piston systems. The Adams Arms piston system is based on the FN FAL piston system which is why it works so well and is so durable. You have a fantastic rifle there, congrats.
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