Roland, Veteran Vaulthunter

Gone Vault Hunting
When Roland, Veteran Vaulthunter enters the battlefield,
look at the top 5 cards of your library,
you may reveal a land and put it into your hand,
if this land was a vault, put it instead onto the battlefield tapped.
{t}{1}create a 2/2 turret and if Roland, Veteran Vaulthunter has a weapon attached, put a ammo counter on that weapon