I don't know whether it was the ammo you used or not. I have been reloading from boxere type ammo that I have bought. The bullets are pulled and I buy them in lots of 500 for $40. They are 146 g. I use Varget powder. I did use some Russian ammo yesterday, but since it was given to me, I don't know who the manufacturer was, nor the year it was made. However, my oldest grandson, 20, was hiting an 8" metal target at 100 yards with it while standing. I hit it once out of 15 rounds, but the rest of the time I was hitting either to the left, right, or just below it. I'm 72 and my eye sight isn't what it used to be, so it has to be the rifle.