You don't need a 20lb gun for a 767.4 yard shot. Normal size/weight rifles shooting "normal" cartridges are perfectly capable LR rigs.
Those rifles work better for the 500-1,0000 yard shots, then the "specialized" LR guns work for the 100 yard shots.....
Those rifles work better for the 500-1,0000 yard shots, then the "specialized" LR guns work for the 100 yard shots.....