The internal weights on the Ace Target forend are 200 grams each, so if you used all 7 Mlok slots you’d add 1400 grams, not 400, for a total of 3.1 lbs. They work great, their only problem is that they’re ridiculously expensive. I added a couple, then added pairs of Salmon River Solutions offset forend Mlok weights. They don’t interfere with the Arca rail, so my Accutak bipod moves easily, the weights are cerakoted and reasonably priced, and I got another 2+ lbs there and have room to add 36 oz more if I want, but doubt I will; it’s heavy enough. With a pound of the Tikka rear stock weights, a 2 lb scope with heavy ARC rings, a 1.6 lb MDT Arca weight, brake, and 1.5 lb bipod, I’m right around 19 to 19.5 lbs and pleased with the setup for a PRS rifle. I’d build something else for NRL.
Obviously other’s mileage may vary, but if I wanted a rifle over 20 lbs I’d have bought something different, or spent more and built a rifle up from scratch with chassis, action and barrel. I get the weight advantages, but frankly think it starts to get slightly over the top after a while. (Or maybe it’s because I can’t get too worked up over 6.5CM recoil in a 20 pound stabilized rifle after shooting 30-06 in a 9.5 lb slung rifle.

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I may still do that build someday, there are so many great options now, but I wanted this Ace Target. My only small complaints were that they had used actual bottom metal, and that it had a folding stock, which I heard is coming next year. I’m happy with the standard CTR mags which feed very well, sit high and fit tight with no rattle, buying two extra, and won’t bother changing out the well for AICS magazines. I also would have loved a 1.25” barrel rather than the 7/8”, but for the $1699 price for the bronze cerakote think I got a fantastic deal for an extremely accurate rifle out of the box, even after getting bent over on the weights and accessories, but again others mileage may vary.