A substantial amount of recoil is used up sending the BCG back, so less recoil is felt in the semi.

Yes youth is just a shorter stock.

A Beretta 391 is awesome, thats what I bought the GF, with a youth stock. I like it so much I use it for doves and pheasant because I can swing it so fast.

I also own an 870 youth that I love for doves, and home defense.