I have never hit a deer in the guts with my .243...But I will say that when I recover a deer and I don't hit exactly where I was aiming....I check the gun...Take your rifle and set up a 300 yard shot, you can do it out of the stand that you were in so your rest and everything else will be the same...Do this in the middle of the day and you won't spook any deer in the area....Shoot 3 shots and then go look at the target...This will tell you if your gun is a 300 yard shooter...I will say...I believe only about 5 -10% of the hunters out there are capable of shooting a 6 inch group out of their deer rifle, at 300 yards under actual hunting conditions...

If the hollow point you were using is the Sierra GameKing 85gt HPBT....I have shot several deer in the 225-275 yard range with my .243...The specific loading was the Federal Premium...I can tell you, that bullet, driven at 3300 + or - muzzle velocity does a very good job at these ranges...