Joking aside, not really. If you want something that does both: 4 and 2 leg varmints, 16 will do the job. Longer barrel from a quality maker will make varmint hunting easier but a longer barrel is less ideal for a home defense rifle. It is the whole reason why the M4 was made, handier carbine for CQB fighting. Twist rate will determine what weight ammo will typically work best in your rifle. FWIW I have dispatched more than a few critters with the same ammo I keep in my rifle for HD.