Round counts do not build proficiency. Familiarity builds proficiency.
There has always been an emphasis on round count in practice, but it's really about meaningful practice.
Making 1000 loud noises with your gun won't do much if you don't pay attention to what's happening to you, and your gun while you make them.
On the opposite end of the spectrum, you would be surprised what you can accomplish with 80% dry fire, and 20% live fire training.
Jeff Cooper recommends taking your (EMPTY) firearm to the couch, and practicing by shooting every "O" you see on your teevee. I can attest to the success of this form of training.
You will be amazed when spotting a target, snapping your rifle to your shoulder, lining the sights on your target, and achieving a motionless trigger break comes as naturally as reaching your hand out, and catching a ball in the air.
It's a good feeling.