Rob is right on about the size of your target. Aim small, miss small is right on.

IfI put a small object (1"orange circle)on a target I can shoot very consistently at it at 50 yds. However, put up atarget with the big black area andI have all sorts of trouble concentrating on the X ring. Especially when the X itself is shot out andI no longer have that white reference point.

WhenI first started shooting I'd take a playing card and start cutting it intosmaller squares the better I got. 1" to start with. then, 1/2", then 1/4". AsI got better even a small target like a 1" circle seemed huge to me even at longer ranges.