jwai86 wrote:I know that 2-7x or 3-9x scopes are often recommended for rimfire rifles, but is there a similar rule of thumb for .223?
I'm not aware of any rule of thumb.
It comes down to being suitable for the purpose, and your own preferences.
I use 4.5-18x40 on everything, but I'll swap on a 10-40x56 if I'm trying to shoot tiny groups for some reason.
I also use a 2-7x32 scout scope for load development on rifles that do not easily mount a conventional scope. I also have some fixed 4x32 and 4x40 scopes, some 6-24x50's, 3-9x40's and others that are useful for testing things.
If you spend any time walking creeks and such looking for close snap-shots on rabbits or foxes you need fairly low magnification, 4-power or less. If I want to be able to see .22-caliber bullet holes in targets at 200m, I need something like 18-power or higher, I need about 9-power per 100m range it seems. If I want to be able to place shots with extreme precision on paper then 18-power is not enough, 40-power is better suited. I don't believe I've ever used a rifle scope higher than 40-power, but some target shooters do.
Nowadays there are scopes with massive ranges, like 2-24x50, 2.5-35x56, 4-48x65 and such. I haven't tried these myself, but I would like to one day as it just seems impossible.