Bungie has stated this: 'My Extra Heavy Ammo perks only grant one extra bullet. All weapons have a cap on ammo reserves; the ammo cap is dependent on magazine size. If you have a gear upgrade that increases heavy ammo to your weapon's ammo cap, it will only add one round to the ammo reserves. Please plan your perks accordingly.' How is maximum ammo reserve calculated though? difficult to plan if we don't know the figure. Could the absoloute maximum a weapon can carry be displayed like the maximum light/discipline/streangth and intelect now are? There is even a space for it to the right of magazine in a weapons details.