
New to me Browning GTI Ultra Sporter
32” Invector Plus choked non-ported barrels with 1991 London proof marks. Will soon be dropping this off to the gunsmith to have a decelerator pad put on and the stuck chokes removed.

32” Invector Plus choked non-ported barrels with 1991 London proof marks. Will soon be dropping this off to the gunsmith to have a decelerator pad put on and the stuck chokes removed.
I’m planning on having the barrels for my 1991 Browning 325 SP sent to Briley for thin walls and was considering having the forcing cones lengthened and barrels back bored. Does anyone have thoughts on this or first-hand experience that they could share?
Edit: bores are marked 18.5 and it is a factory fixed choke gun with improved modified over improved cylinder chokes.
Improved modified over improved cylinder fixed chokes. Now to figure out how long it will be until I send it to Briley for thin walls.
Some additional pictures in the comments
Looking at a Miroku Mk38 Trap and these are the fixed choke markings. I understand that the top is a full choke but I’m a bit confused about the bottom choke marking because I know the *- is improved modified however I’m not sure what the plus means. Light full? Something else? Any help would be appreciated.
Picked this Miroku Mk70 sport earlier today and put a few boxes of shells through it. I was curious if anyone knows a retailer selling an adjustable comb Browning or Miroku buttstock that I could put on here?
14.5 MRP-L with ATACR 1-8, piggyback acro, rc2, etc etc