I installed the Tuner on the 40X BR rifle last week. Only had a little less than 4 boxes of SK Pistol Match. I shot some control groups before installing. Took most of what was left to find a good tuner setting. I ended up when the ammo ran out shrinking the group by HALF. Pistol Match is a little faster than Rifle match so wont be using it in matches but looks good. Ordered a brick of SK Rifle Match, Lapua Center-X, and Midas +. Hopefully it will get better. I shot the Rifle Match in the last match of the year in sept in two matches. Won one and placed 2nd in the other (lost on Xs). But that was Factory class without tuner and off bags, front and rear. It did shoot 4 clean targets tho. I want to see if a little better ammo will be good enough thru the tuner for 50/50 Unlimited and ARA. After shooting this ammo up I will get a mechanical rear rest.