With a 30-30? That's quite remarkable.
With the .375 Winchester, I show off with the grandkids with this. Not often, though, I will admit - the shells are expensive and the recoil can kick like a mule.
Although, I will admit, it was a childhood friend's father who could do this with his .30-30 - he was my inspiration. I had seen it done, time and time again, effortlessly.
So, I practiced with my own favorite until I could do it as well. Lots of hogs, deer, and bear can mutely testify to this. Not easy, no, especially once I had to get glasses as I got older, myself. The grandkids laugh, until they look at the can.
Then it inspires them, as well. You don't need doodads fastened all over your rifle to make a shot.
EDIT: Part of the "trick" shot is knowing your holdover, how the target is positioned, and old-fashioned Kentucky windage. Ballistics are simplified within 100 yards on a single cartridge and loading, with much practice. The other part is confidence in your ability to call a shot. Then make it.