[blackdog]

This shooter is this good due to practice, training, and equipment(including evasion tactics). I am sure there are not too many places you can practice shots like this without being witnessed. People this good belong to clubs, have awards, medals, reputations, and notariety. They had teachers, custom made stuff at gunsmith's, etc... The shooter is extremely familiar with the area's terrain, LEO tactics, traffic patterns, and public travel patterns. All those factors would lead me to think it is a government employee or former military/CIA type. I'm sorry to bring it up, but the situation warrants considering what would be horrible(like it already isn't).

[OReilly]

All those factors would lead me to think it is a government employee or former military/CIA type.

How about an ex-Montgomery or PG police officer that use to do (off-time) security gigs for Michaels

[Lloyd227]

"People this good belong to clubs, have awards, medals, reputations, and notariety. They had teachers, custom made stuff at gunsmith's, etc..."See post #84

[dirtboy]

I am sure there are not too many places you can practice shots like this without being witnessed

There's a place in Michaux State Forest in South Central PA that is a target range for sighting in rifles - pretty close to MD and DC. Doesn't get a lot of use, a guy could just wait for the place to be empty to get some practice in. There are probably lots of other such places within a few hours drive of the area...

[r9etb]

I am sure there are not too many places you can practice shots like this without being witnessed.

Sure there are. You're thinking the guy goes to the shooting range, but he could also just head up to the hills for some "hunting".