I agree with James B. The 243 in my opinion is more of an experts caliber than a beginners. I say this because there is no margin of error for this caliber on a deer. You must also use a well constructed bullet. I have used the 243 on deer & feral hogs in the past. I have always used 100 gr. Nosler partitions when using the 243. I will agree with James B and say that in my opinion 25 caliber is where deer calibers start and some 25's must be eliminated like the 25-20 and other anemic calibers that still exist. If I were buying a novice a new deer rifle it would be chambered in 25 WSSM, 25-06, 260, or 7MM-08. As for varmint rifles I find the 243 more caliber than needed and prefer the 223 & 22-250. The 243 is useful in very long distance shooting if you aren't firing 200 rounds per day. The kick of the 243 becomes quite noticeable after 70-80 rounds. This is just my opinion.