Need help with adjustments.

I'm starting shooting trap after 14 year layoff and trying to shoot a BT 99. Patterned the IMOD choke today and it appears to be 55 / 45. I'd like to be shooting 70/30 or even 75/25. The gun does not have an adjustable rib but does have an adjustable comb that is currently raised about 3/8 inch. Will raising or lowering the comb make the gun shoot higher?

 

Raise the comb to raise the POI and lower to lower POI
Then if you can lock the trap to straight away on 3, shoot until you are smoking the targets and then move around to other posts and see how you are hitting the birds. Check your cap yardage to.

 

grizquad, Contact Dave Berlet, tell him length of barrel and point of impact that you want, he can make you a rib to raise it as much as you want. Simply raising the comb is not the way to do it. You will be seeing rib between the beads. It is very hard to see the same amount of rib for every shot. Roger C.
Dave is a poster hare, send him a p.m.

 

I failed to mention. It will set on top of you existing rib. No alterations are made to the gun. Roger C.

 

Just to clarify so , you will understand your adjustments !
IF your iris is resting on the center of the rib , when you're mounted on the gun , as if it was a marble on a table ?
Look at you guns rib , from the side , see how it is tapered towards the muzzle ? That's because the gun is setup to shoot higher the 50/50 !
If the Rib was parallel to the barrel , it would shoot 50/50 ! Now with adjusting the COMB UP , the angle looking DOWN at the rib , will make
the gun shoot Higher . Usually with a 1/4" gap between the front and rear BEADS , looking down the barrel from a properly mounted gun ,
will give you all the height you need ? Your Mount , needs to be consistent , each and every time !