First of all, new production factory ammo for the 7.62x25 is not corrosive. Look at S&B or Winchester (repackaged S&B last time I checked). Now surplus ammo for the round? You bet it's corrosive.
I haven't done any reloading for this cartridge, but there is data for it in Hornady's 6th edition manual. They only show 90 grain XTP bullets, but they do show data for H110 and W296. No data for Unique, though.
That 85 grain JSP you have may be newer than the 6th edition manual. If so, it would presumably be in the 7th edition manual.