What gun are you shooting it out of? Are you going to shoot matches?

I'm going to turn this around and let you think about it from a different perspective. Is surplus powder good enough for AMAX or other match type projos.

Unless you're going to a be shooting in FCSA sanctioned matches, I say yes. Everything is based on keeping everything as close to the same as possible. From your brass prep to how you hold or don't hold your rifle.

Do your brass prep the same for each piece and if your really serious (anal) separate it by headstamp and year. Separate the projos by weight, try to keep them as close as you can. Buy everything by the case if you can, that should keep everything really close.

As for the powder, get a good scale, digital would be the best. Dump the powder into the tray on the scale until you're within a few grains of where you want to be. Then add by a grain or two at a time until you hit the charge you're going for. Do this for every round that you load, even WITH surplus as this is the topic we're discussing.

From here your going to load your bullets into the case. As with everything else, seat them to the OAL that works best with your rifle. Be sure that each one is the same as the other one, check one every few rounds to make sure the die hasn't moved.

I would only load about 10 the first time with the surplus powder that you plan on using. See how well it shoots, if you have a chrony, check what kind of spread you're getting on the ammo. If you're happy with the results, load up a box and go to the 1000 yard line and send them down range.

If they hold 10 inches or less, that's MOA or better and that's pretty damn good for surplus powder! Not to mention that the shooter was doing his part keeping the rifle on target! Any little change that you do will effect your accuracy down range.