By the way, what Powder are you using ?

Just on the off chance try these.

Change ONE thing at a time and dont forget the 10% rule.

1. Try a different powder
2. Change Primers
3. Change the seating depth.

Now I know it is very unlikely to make 12 inches of difference
but worth a crack.

Re front sight, what about removing it and getting another dovetailed in - although 12 inches, you might need to do something else as it just may end up looking wrong.

Keep us informed.
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