Last 2 days of rifle season i decided to just try and get some meat in the freezer so i took my 223 out. Its a remm 700 vtr and i have a nikon coyote special with bdc on it which is calibrated for 55 grain 223 bullet. I was actually using 50 grain jhp. I took it out because i was going to head or neck shoot any doe i saw. One day i shot a doe in the head from 30 yards away and dropped it were it stood i took its face off. Then the next day i shot one in the neck at 200 yards away at a full sprint.....was aiming at head but the neck shot dropped it in its tracks. My question is what would one of the best bullets to use for deer but to keep in mind i dont want to stray to far away from the 55 grain because of my scope calibration with the bdc because i do use the gun alot for fox and coyotes. I wasnt sure if i just got lucky with that neck shot for it to drop like that but i really like the way the 223 doesnt really ruin any meat there was a entrance in the neck but no exit. Hunting deer with 223 is very new to me and it never crossed my mind untill this year to use it since its a dead accurate gun. Im just wondering if anyone else out there has experience with a 223 for deer and if your bullet went through to the heart and lungs or will it have a rought time getting through rib cage. I was looking for something that could be effective up to 300 and maybe 400 if need be.