[Black Sheep]

We have slugs now that are designed to pass right through a car door or hood to punch a hole in an engine block, so I don't see why you wouldn't be able to purchase any of the variant ammunition available for other weapons for a shotgun as well.

[Aryeonos]

You're all bringing up realism in context of SR ammo.  Go to the corner and think about what you've done.   

OP: Ask your GM what they think.  If they're cool, go nuts.  If not...well, I'm sure you can find another option to kill drones with.

+ 1 for the stand in a corner comment, I am the DM so I am asking you guys. I am just having an issue with an anti vehicular, high velocity round coming from anything other than a high powered rifle or an assault cannon I guess.  But I guess if the rules allow it then screw it I should right?

It's not just the rules, we have them today, we also have armour piercing subsonic ammunition (Well the russians do) called PAB-9 ammo. You don't need a high velocity small bullet to pierce armour, in fact allot of ammo works the opposite to accomplish its criteria.

Here we have Steel Slugs
And subsonic armour piercing rounds