This discussion may contain spoilers!
Ok. So, there are some realism problems. I'm not going to talk about Clem.
First, Carver's team come. With AK-47 guns. And, they headshot zombies without aiming. Yeah, they even not aim, holding guns near waist. And, AK-47 got huge recoil. Doesn't matter you aim or not, huge recoil. You can't keep firing for seconds and hit correctly. And they are not professional soldiers.
Second, Kenny shoots Carver in the shoulder, with hunting rifle. But it didn't effect, he stand up and use his arm without problem, and shoot Alvin. Wow, I mean, he get shot. Min. caliber 22LR, but still effective. People hunt animals with it. And, it couldn't stop Carver. Like I said, didn't effect. But, it can be stronger caliber than 22LR. So still, he can't act like nothing happened.
Look, it hits Nerveous System. Plus, he didn't do anything to stop bleeding, too.