Gun shooting low

[la_dxt]

Has anyone experienced a gun that shoots about a foot low after changing chokes and backboring a barrel, like hitting the ground in front of the target ? I bought a Rhino choke and had them backbore my 11-87 barrel last year. When I got it back, I checked the pattern to see how much improvement was made. At 40 yds  it was shooting extremely low, so I got some TruGlo magnum gobble dot sights to try. I had to run the rear sight way up, past the end of the base (the adjustable top sits past the base, overhanging and I'm worried about it catching on limbs or vines and getting pulled off. Actually I'm having to aim at the actual head of a turkey for the densest patter to hit where it should, and I have ran out of adjustment on my fiber optic sights. I have thought about adding a rail and getting a EoTech , but lately I've been thinking of trying an IC or other choke just to see if that's what the problem is. I should put a factory choke in to see I suppose, but any advice or ideas would be appreciated.

[Rapscallion Vermilion]

(One newbie to another)   Just some ideas ....  That sounds like a big change from before the work.  A number of things can go wrong between backboring and installing a choke, generally having to due with the choke threading being offset or canted, the new bore not being true, or a barrel getting bent.  First thing to do is check the barrel off the gun.  Hold it up to the light, look down the bore, and see that it looks reasonably straight.  Most aren't perfect.  You should see something like concentric rings when the  muzzle opening is visually centered within the forcing cone walls.  Bent barrels can be fixed.  Next check the barrel wall thickness at the muzzle with the choke removed.  Does the barrel wall metal look even all around?    With the barrel off the gun, look down the barrel from the muzzle end.  Does the choke threading look concentric?  Definitely try a different choke.  It is rare, but you could have a bad one.  As a remedy, you could also switch out the gobble dot front fiber optic for something that lays low along the barrel. That would let you back off on the rear sight.   Did you test it with your hunting loads?  My hunting loads shoot noticeably higher than light target loads.