FPS here on AO would be worth talking to. He does quite a lot of this kind of work from his posts on here. He also does screw in chokes. He is very knowledgeable from the info he has passed along on other threads. Never had any work done by him but would definitely try him out next time I need some.
So I cant recommend anyone in Edmonton area but I will add if you are opening up an old Belgium to enable you to shoot steel shot I would go a little more open to Improved cylinder. Every 12 gauge shotgun (about 6 now and one 10 gauge) I have patterned with steel shot had better results with improved cylinder than modified.
Opening an old 72 Belgium A 5 3 inch
a hunting we will go!!!!!!
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