If you're looking for the PRI rail to save weight, it's not exactly the lightest option, despite being carbon fiber. I absolutely love my PRI Delta forearm on my Mock12 build with Ares BTR below (ignore the CA legal grip), but there are cheaper or lighter rail options available if weight savings is your primary goal. With that being said, it's a classic, it feels great in hand, and it looks f'ing awesome. Sometimes you just need to go with your gut and get what you really want from the start.
If you're building a 16" rifle with the PRI rail, I would pair it with this CLE Douglas SS barrel for your own Mk12 Mod H style build. This is a bit heavier than the Faxon barrel but should be a much more consistent (precise) shooter, and has the benefit of being more "clone-correct" if that's important to you.
Douglas-SS: Modified Tactical Barrel .850 UHG .750 Gas Block .720 Muzzle Length: 16" Twist: 1-7 Chamber: Wylde Gas System: MID Thread: 1/2-28 Finish: Polish
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