Seriously, I would load up 5 or 10 rounds and test fire them before you load up hundreds of anything with them. Odds are they are fine, but the one single time I ever got burned was when I bought a brick of primers from a "friend" who decided loading just wasn't for him. Multiple hangfires, and at the time (probably 30 years ago now) those primers were only a few years old! Honestly, in all my years reloading this was the only bad experience I ever had buying used components, but it left an impression. Now I immediately test anything used.

Like I said, odds are they're fine. I hope so, and good score for you if they are!