Kitt, cool fun, but too bad you sacrified some potentially good equipment. Even if you just used it for steel plate shooting protection, it would be good to have. Shot vests are not considered reliable as they may not protect if hit in the same spot. Manufacturers suggest replacing them if shot.
Tman, do not wash in the machine unless it says you can. Most ballistic vests are rated for 5 years. Like on milk, some expire by then, some don't. Whether or not they expire has to do with how much they are used. Sweat, moisture, and heat will do a lot of unseen damage to the fibers. Unfortunately, there is no way to test an old vest, that I know of, to determine if it is still properly rated.
A Level III (not IIIa) vest is rated for .308. They are not normally standard issue, but some departments might. I would not want to be in a vest struck by a .308 unless it hit a big ceramic plate first. Even then, blunt force trauma can be hugely painful, better than being dead, but just because the bullet does not penetrate does not mean life is peachy. The Second Chance "saves" book shows a lot of people, mostly guns, showing their vests and bruises that occurred underneath. Funny, several seem to be in hospital beds as I recall. Some people are rendered unconscious by the blunt force trauma of even pistol rounds. Some never know they have been shot. In real life with no vest, some don't know they were shot. It just depends on the hit placement, mind set, and adrenaline. As a result, some collapse AFTER being shot and AFTER the finish chasing down the bad guy.