MARKUS, I'm pretty sure that my post is the one that came to mind re: filing the front sight down to gain elevation for my Tracker II!
I tried several different sabot slugs until I found the one for me. That one has plenty of power in a 2 3/4" shell, great accuracy at 50- 100 yds. , yet allows me to shoot more than 3 rounds at the range without needing a sling for my shoulder!!!
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Then, I bought 2 cases of the same lot #......I think of the 50 boxes I've used 6.....those slugs go with that gun......but they will stay with me!
fortress49, granted, that the T..II has a rifled bore, but the process would still be the same.....I don't remember the title for the posting, but I did post some regarding sighting in my Tracker II......
Ultimately you want your rear sight in a middle setting with your slug of choice to allow some fine tuning....If you decide on a particular slug type and load that will be THE load for you, THEN you figure out how to get the sights right.....hopefully they will shoot at least a little low, to enable you to adjust the rear sight to approx. the middle, then bring a file with you to the range.....shoot a couple ... file the FRONT sight down a little to raise POI.....COOL THE BARREL....shoot a couple.....file a LITTLE more....until you are hitting 1 or 1 1/2" high at 50 yds....[or whatever you decide your goal is to get you the zero you want, be it 75 or 100 yds.... Doing this with the rear sight at the middle setting lets you fine tune your group a little if you happen to get too zealous with the file.....