Before you scope any Mosin-Nagant, you may want to shoot it with iron sights first. You may be wasting your efforts. Bore condition on these rifles range from new to totally worn out. If you permanantly alter the rifle, you may live to regret it. The supply of these rifles is drying up, and the price is going to increase for the authentic, non-altered rifles.
"It is better to be too skeptical then too credulous"