I believe the Choate "tactical" stock has a butt hook already. As for filling the hollow stock... You must plan on mounting a wheeled chassis to this thing! Lol. I didn't choose the Choate because of the hefty weight. However, if solely off the bench or prone I suppose weight is irrelevant. I also believe Choate offers an adjustable cheek piece as an add on, but I don't remember how much the kit is.
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