I will say 225 yards with a 120gr charge. You'll have about a foot of drop with a 250gr shockwavebullet when sighted in 2.5" high at 100yds, and about 950ft/lbs energy. I know for a fact that shockwaves work well around 200 yards with such a charge.I don't know how slow that modern jacketed bullet will open up, which would be the real decisive factor for a precision shooter. If it could still perform at 1100fps I'd say 300 yards...about 700ft/lbs energy but the big bullet could easily make the target dead, fast.