Randy in VA
The problem with the betting type folks is that they tend to make the situation impossible and/or it becomes a never ending additive series of conditions: real, conjoured, imagined or worst "a once saw/heard of a guy do this". "Yeah, that's it: 900 yards, double crosswind, 30 mph, moonless night, borrowed gun, mixed manufacturer ammo, out of a truck window (moving truck, corduroy road), etc, etc... you know, just like real hunters do it!
Seriously though.
For a new guy, I'd say LongRange begins where he/she needs to THINK A GOOD DEAL about what's required to get the bullet on target, and then also analyze his/her various variables and make corrections BEFORE the shot. If you're not doing this, the shot is natural to you and therefore more than likely normal distance or you're just a poor marksman.
----- "Oh, I forgot to tell you... you gotta make the shot 4 times while blindfolded or the bet's off!"