I store my handloads in military ammo cans I expect they will last as long as any commercial rounds. Some of my handsloads were really getting a little age so I used them up I have nothing left older than 5 years old now. I cowboy action shoot try
www.sassnet.com for the governing body for the sport. This is a high volume shooting sport lots of shooting say approximately 50 pistol, 50 rifle 25 shotgun a match not to mention time and rounds spent practicing. Like you I handload for stress relief supprising how quickly you can fill a 30 caliber ammo can with 38's when relieving stress.