Again, stay with the .22 rimfire, and don't confuse your kids with different kinds of rifles until they know how to shoot safely. Don't confuse yourself, either. A bolt action is better than a semi-auto for this, though some will argue. The thing is, use one rifle until some proficiency is gained.
News today from the CPAC conference is that the NRA and other conservatives are confident that really restrictive new laws will not pass. If this is true and unfolds that way, we will again be in rimfire ammo up to our butts.
And, since when is the .22 rimfire not acceptable for hunting?