There is a difference in the lubes. SOME will last for years, while others aren't any good after a few months. Are you CERTAIN those bullets HAVE lost their lube? There are LOTS of "invisible" lubes used by the major ammo companies. I found a box of 45-70 bullets made by my grandfather in the late 50's. Being about 30 years old ,(the bullets) I thought they'd be only good for REmelting. On a whim I tried them in my Contender pistol.I figured the short 14" barrel would be easy to clean IF the worst happened. I was surprised at the accuracy and found NO leading in the bore. I loaded a a bunch for sillywets and got 30 hits from 40 shots! I have to admit,the misses were operator errors! Recoil was more than I expected and flinches developed after 20-25 shots and got worse as the string continued!