There are several things that can affect accuracy. Most shooters are aware of OAL as it relates to the distance from the ogive to the lands. Bullet construction affects it as well. Copper versus cup and core. How thick the jacket and the lead hardness influence cup and core bullets.
The single biggest factor for me however is reliable functioning. Animals fall over whether the rifle groups 1 inch or 3 @ 100 yd. To a point. For deer, my yardstick is an 8.5x11 sheet of paper. If I determine that the maximum range of encounter will be 200 yd., then as long as my handloads hit that piece of paper, it's golden.
If the max range is 400 yd, as long as it hits that paper, I'm happy. That is why I make my own targets using 8.5x11 paper. It's not just convenience of std sized paper.
I like a clay pigeon at 300 yards standard.
