The vast majority of the time it's a Remington AR-15 topped with an 80's Simmons 2.5x10 Aetech scope with 50 gr hollow points. Most my shots are under 200 yards and this has worked well so far.
Longer shots are handled by a DPMS LR-260 with a 2.5x10 Burris firing 120 gr Ballistic Tips or 123 gr SST.
