Too many factors to decide that. Depending on bullet, velocity, etc., it could. Meat damage is really not an issue, if you shoot them through the lungs, neck, or head. If you shoot a deer through the shoulders, you may lose some meat, but there is not that much there anyway and you will have a dead deer right there. Don't shoot them in the ass, or the back strap and don't worry about the rest.
I don't think increased velocity will affect meat too much. But it is hard to do apples to apples with a .050 difference in diameter. Most .243 hunting rounds fall under 100 gr. and most people I know use 150gr for a .308. I haven't given a lot of thought to meat damage because I try to shoot either in the neck or behind the shoulder.
Meat damage is caused by bullet fragmentation or bone shards not velocity. Shoot a monolithic bullet like the 85 grain Barnes TSX and the.243 is great. If you shatter bone with any bullet you are going to have some bloodshot meat.
Some meat damage is caused by the kinetic energy imparted to the target, so velocity can be a factor. The formula for kinetic energy is 1/2 the mass of the bullet times the velocity at impact squared, so the velocity can actually have more influence than the mass of the bullet. It is complicated by the fact that the more mass a bullet has, the better it maintains it's velocity.
Having used both, I would say the short answer is "no". However, I have seen the .243 make quite a large hole using Winchester 100 gr Super X ammo, whereas the same shot placement (broadside lung) with Fusion 95 gr resulted in a fairly small hole. Probably due to the relatively short ranges involved since the Fusion is more of a controlled expansion round vs the Super X. Point is the ammo choice might be a bigger variable than the caliber difference in some cases. You guys with more experience tell me if you concur.
I have owned and hunted with both calibers for over 30 years and can say without a doubt there isn't one iota of difference.. Killing close to 100 deer total with these 2 calibers.. Bullet construction and shot placement are the defining factors in meat loss...
I use Speer 100 grain BTSP in my .243, on the whole it's absolutely fine, I use it on the lightly framed roe deer right up to the big Red stags we have, no more damage than my 30-06, but I use a soft point, people I know use sst's and they just create too much damage.
There have been a few times I've had a bullet fragment from a .243, there was a lot of meat damage. That was more an issue with the bullet than the cartridge. I want to say those were Core-Lokt and Winchester Silver Tips. Barring bullets flying apart on impact, .243 and .308 seem to do similar things to the meat, but I'd also say I've actually never seen a .308 bullet fragment.
Kind of an interesting question. Could be that all else equal, bullets tend to fragments more at .243 velocities. What's more, I've shot a lot of deer in both cartridges using Interlocks and never had one of those go splat.
All I can say is what I know about the .243, I have never owned a .308. My youngest son shot a nice whitetail buck at about 90 yds. The buck dropped dead in his tracks. The bullet slipped in above the right shoulder and passed through the left leg, it turned and traveled in and out the left leg, landing just under the skin above the hoof. There was absolutely no bloodshot or meat loss. The 100 gr pills are lethal on deer sized game.
It has not been my experience that .243 causes more meat loss than .308 shots. My shots were all at whitetails inside 100yds, all quick kills with .243 100gr winchester power points, and .308 150gr interlocks.
Difference was debatable but seemed like .308 had more tissue trauma damage, still not excessive. Sample size 3 each caliber. Ive killed many more with 130gr .270 core lokt and its not a meat ruininer either.
Lost a whole shoulder last year though my fault