As Andre says, shooting is the only way to knmow for sure. However, looking at the issue from an engineering perspective, the barrels of a double shotgun are made to converge at 40 yards. Such an angle of convergence will cross badly downrange of 40 yards. So, DR or bore rifle barrels need to be bent essentially to parallel to regulate at longer range. For whatever reason, the bend doesn't usually degrade the accuracy potential of the individual barrels. Cape guns are sometimes regulated without the bend. I have a Savage 24 12X 30-40 (rechambered 30-30) with a rifled tube in the shotgun muzzle, which shoots saboted 12g slugs and 30-40 180 partitions at 2400fps into a combined sub 3moa, that with a 3X scope. Maybe that's just luck, can't say as this is the only combo gun I've tried it with.