Due to difficulties in getting Sako factory rounds I have started home loading. I loaded some .222 55grn Sierra Gamekings with 21.6grn Viht N130 powder and Federal small rifle primers Case overall length 2.124". I fired 12 rounds at 100yds in a tunnel range with 10 out of the 12 in the bull the other 2 outside but just touching the bull. I then reloaded using exactly the same components the only difference being the overall length 2.122" to my amazement firing in the same tunnel all the bullets were approx 1.5" higher and to the right. I was wondering is this nomal that 2 thousand of an inch difference should give this result.