Come to think of it, I first equipped The Crest of Alpha Lupi. I didn't notice any increase in ammo capacity with the UR though, despite its "Special Weapon Ammo" perk. I ended up switching to my IB armor though, so I could preserve my exotic slot in order to get both increased shotgun ammo and reload speed. Because of this, I didn't think a lot about it. I will double check the special weapon ammo perk, and if that's not working either, then I bet that whatever is keeping the "Special Weapon Reload" perk from recognizing the UR is probably also messing with the "Special Weapon Ammo" perk.

I run with the Iron Banner Titan armor. It grants more ammo for scouts and shotguns, which is awesome for me. (Since I am running with the UR, and the Secret Handshake) [spoiler]My secret handshake has full auto, and is a superior backup/panic/spray-and-pray type weapon. (The thing will spit out six shells in less then two seconds)[/spoiler] With the armor, my max ammo with the UR has increased by about 5 rounds. So not a ton, but the fact that it boosts ammo of both my primary and secondary is really nice.