Shot placement / Bullet choice

[Josh C]

I have a question and would like to get everyone's opinion. We hunt in Avoyelles parish and shoot big body deer. Our average 3.5-5.5 yr old buck will weigh 225-265 lbs. The last 3-4 deer dad and I have killed, we have not had a pass through of the bullet, which make them very heard to blood trail and sometimes impossible to find. We try to shoot them braodside in the lungs or heart area, and tend to not take bad shots. He shoots a 270 with 130 grain Hornady SST bullets and I normally shoot a 300. I tend to get pass throughs with my 300, but on Monday of this week, I shot a good 8 pt that weighed 225 lbs with my .308 instead of my 300 and didn't get a pass through. I shot it with a 150 gran Hornady whitetail inerlock bullet. It took us till Tuesday late morning to find the deer with no blood trail. I hit it in the boiler house and destroyed the inside, but didn't have any blood to follow and he didn't drop in his tracks.

What is everyones perfect shot and what type bullet tends to get a pass through? I know our deer are big bodied, but you would expect to have an exit hole if you shoot the deer in the lungs and don't hit any bone.

Thanks.