I can only think of three "speed" methods of carrying spare ammo for a J-frame: the HKS speedloader, the Safariland Comp I speedloader and the Bianchi Speed Strip. Taking into consideration that I use my J-frames as BUG's, I like the Comp I for pocket carry when I'm using a covering garment with side pockets, but usually just stick a Speed Strip in my pants pocket.
Steve