Yes, the 7.62X39 tends to penetrate a bit....
So, using Corbons or magsafes, if you can find them and test them for reliability, is a great idea.
The shotgun one is better. You can get some short pumps fairly inexpensively, or buy a combo gun with two barrels to fulfill 'other' requirements.
That said...my home defense gun for a while was an AK loaded with corbons...I could not afford a shotgun, not had a lot of use for one. And lived in a less population dense area. Still do not really have alot of need for a shotgun other than HD , which can be serve fairly well by what I do have at the moment.
Mainly I rely on a 1911 .45(or several actually...the AK is stashed in a safe in another state) and a recent addition of a mechtech carbine conversion unit for one of the 1911's in my collection.
Not a perfect 'battery' but my apartment is real small and ranges will be real close. I have .45 mags stashed in all sorts of places...so it keeps it simple for me...same ammo, same mags...45 caliber thump.
Mainly I use 230 gr jhps, but the first 2 HD mags are 185 gr silver tips, cause they tend to penetrate less.
But ya never know what might appear in the domicile after I get back from the gunshow on Saturday?
Jercamp45