I hear so many people say that their factory ammo shoot well in their gun. However I wonder how many don't realize that the mfg could change the powder type they use and the ammo will not group or hit zero where the other lot of ammo hit on the target or game animal...
One reason to reload..
Also if you want to reload to factory velocities..Go to the factory ammo publication..Look up the velocities for the bullet grain and then find that velocities for the same grain bullet in the reloading data book and or web..
I often wondered if the factory bullet mfg jumped around to different powders instead of using the same one for year after year after year?
When I do use factory rounds and don't get to the range.. it does start to make me think... "I hope that Remington, Winchester and or Federal used the same grain and type of powder as the box I zero'd in the rifle in the first place?"