Bolts are shorter. They tend to be heavier, but I think they follow the same weight to draw weight ratio as arrows. A crossbow could have about 200lbs draw weight, but above 70lbs is uncommon for a bow. There can be much higher draw weights, and I guess in a fantasy setting getting over the world record of 200lbs draw on a longbow is likely.
Rule of thumb, shorter than 16inches is a bolt, longer than that is an arrow, but about 20inches. Normal arrows would be half an ounce, bolts an ounce. And if you wanted to be picky, your high draw bow needs heavier arrows for full power.
The Pellet bow fires B projectiles.
Are there crossbow bolt equivalents of blunt arrows?
Nope. Another reason never to focus on crossbows in Pathfinder!
There should be, as they were a real thing. Good for hunting small game because a) they would kill the bird without shredding it, and b) they wouldn't get buried in the ground if you missed. Not so much use in a combat situation, of course.
Are there crossbow bolt equivalents of blunt arrows?Nope. Another reason never to focus on crossbows in Pathfinder!
Bolt ace 5/hunter, heavy x-bow, with gravity bow and vital strike line, is a pretty nice boss killer.
Looks like I missed a word(there) in the title. Sorry about that.
Only barbed and incendiary arrows appear to have a crossbow equivalent.
I don't see any reason for them not to exist though. They're more common in modern times where over penetration is a problem, but they did exist in the past as well. I don't really think arrows should be able to do bludgeoning damage, but since they can then bolts should as well.