Can you use a modern peep sight on a percussion ML rifle, while hunting deer. yes, during the black powder season and throughout rifle season.
Is the in line rifle with Pyrodex pellets legal for the regular ML season? Pyrodex is legal in any season black powder and regular rifle. the inline is not legal for "flintlock season"
Can you use a telescopic sight during regular ML season. Yes, during the black powder season and throughout the regular rifle season.
An easy way to figure this out :
Flintlock season is for "Flintlocks only" primitive sights only.
Black powder season is for any black powder rifle (there is a minimum caliber requirement) be it percussion, inline or flinter. Telescopic sights are allowed.
There are no restrictions on powder type or projectile in any of the seasons.
All of the above described BP weapons are legal for the regular rifle season as well.
Can I ship a ML rifle to a citizen of PA without shipping it to a dealer? As answered before by another knowledgeable fella, YES.
Hope this helps!! Good Luck!!