What do you mean they are loose? The limbs will seem loose when the bow is unstrung,they are not supposed to be locked down tight.They use Hoyt formula or buffalo limbs.Which is like an ILF just longer from the dovetail to limb bolt.The tiller and a slight weight adjustment is adjustable.I put the limbs on and string it up,then measure the tiller the distance from the riser to the string.I adjust the lower limb to be an 1/8" shorter for shooting split finger.You can adjust it even for shooting 3 under.Just back off the set screw on the limb bolt and then you can adjust the limb bolt to the tiller you want.You don't want to bottom the limb bolt to where you can't remove the limbs when unstrung.
The Hoyt Buffalo is a nice bow with the adjustments you can do to fine tune it to you.You could probably fine more info on setting it up on Youtube or Hoyt Archery's site.