My father (age 76) has had some rhythm trouble with his heart. He had a defibrilator installed in his chest, and all is great.

He is an avid hunter and at our farm in WV he has always used a Rem 600 carbine in .308. This is one hard kicking little gun. It weight in at about 4 1/2 pounds and just delivers a thumpin. It's never been an issue...but now he isn't supposed to have any "sharp" jabs to his shoulder area.

My question is...what gun/caliber combo has virtually no kick and is still a suitable caliber for whitetails....small whitetails. I have a .223, and I've killed several deer with it. He isn't quite the shot I am and I'm a little nervous about turning him loose with that.

I've looked at a 7mm-08, 7.62x38, and .243.

Any help is appreciated...and please don't give me an ethics course on the energy needed to kill a whitetail. Thanks!