The whole point of the BDC is to get people shooting accurately with their own .22lrs. That experience translates to all your rifle shooting. I maxed the BDC using a CZ 452 American with a Bushnell Banner AO scope. I did it about 5-6 years ago with bifocals. Even with a pretty good .22 and a decent scope, it is a very difficult challenge and took me weeks to do it. I was so much better a shooter afterward.
I really had to go back to basics, or more properly BRASS:
B - breath
R - relax
A - aim
S - stop your breath (I stop at half way)
S - squeeze the trigger - let it surprise you.
The eye thing was a challenge. I just shot a lot and found what worked best for me. I have seen the benefit in all my shooting too. Good luck!
 6.5x55 Swede @ 50 yds. |  6.5x55 Swede @ 100 yds. |