My son with his .270 Win. 40 yds and 52 gr. H414 130gr core-loc. was a bang flop. If ya don't want it to run shoot it half way up the body right in the shoulder.

Wrong! Assuming you are using the right bullet (which the Core Lokt is one of many!) A bullets flight time is only a few fractions of a second! In fact, more speed= better expansion.
Most people seem to think that a small exit wound is always the bullets fault! But, even with a good bullet and a well placed double lung shot you can still miss bone and end up with a small exit.
With a .277 bullet, even if it doubled it size, would only leave a little over a 1/2" exit!
Impressive exit wounds are a combination of a good bullet + speed + hitting enough bone/meat for the bullets energy to push that extra bone/meat out the other side.

Also, I won't argue that there are not better bullets than the Rem. Core Lokt, but the Core Lokt is a darn good bullet too!
In my younger days, I have blamed bullet failure! Most people do! But, the reality is that most of the time its not the bullets fault!

Too old to change and have a problem
 

Did a lot of close range hunting in swamps, when young. Instant knockdown of deer was a necessity.
Aways used bullets that weighed at least 165 gr. or more. Slow was ok. 35 Rem exited every time but once. Never went to ultra high velocities for close range hunting.
Lung shots are effective, but never took a lung shot. Went for the shoulders and the main artery running from the heart to brain. Use bullets manufactured twenty years ago and now.

In archery never blood tracked deer. Used a compass reading from the stand site. Blood tracking was far secondary. Directional bearing and big deer on the ground was primary.

Too old to change; too old to recommend to newbies.

BAH! You have a ton of info to share good-sir.

The younger among us are in need of such advice. Do not underrate yourself!

Switch caliber!

Bs...Nothing wrong with a .270...Only thing wrong is the OP doesn't have much experience so he doesn't know what to expect...

Read the part where he needed a tracking dog for a deer that went 30 yards!!!

Thats what I thought early, but didnt say anything. If you cant take down a whitetail with a 270 then a 300 win mag wont do you any good.