As most anyone who has followed this board very long knows I am not particularlly fond of .410's. That said however I tend to agree with Chuck H here. In fact I would go even further & say a small person can handle a heavier recoil from a well fitting gun than one which puts them off balance to even hold up. I am not of course advocating excessive recoil, just saying the fit is most important.
Also I will go out on a limb & say that most likely the big drawback often associated with the .410 for a beginner is not so much the gauge as the gun itself. A single bbl'd .410 built on a full size 12ga frame is not a particularly well balanced gun & the hammers are often too much for small hands to handle effectively. Add to that they are most often full choke. Any full choke gun will normally give a higher concentration of its pattern to the central core. Larger gauges with a heavier shot charge may still have a dense enough pattern in the fringes to give a larger "Killing" circle, but not the .410.
Make sure the gun fits & feels right to them, use a choke that will give the best pattern out to 20-25 yds (forget the oft stated Fact that a .410 requires full choke to be effective) & the .410 should be fine for a small person to start with. At this point in time they shouldn't be trying 40-50 yd shots anyway. They can grow into that.
