Just purchased several boxes of FEDERAL .40 cal ammo in a white box with a label marked: XMP40HST4 135 gr. JHP "reclassified ammo". I was told it was a govt. contract over-run. Priced at $17 / 50rds., it seemed like a good deal in a bullet weight I've been meaning to try. Does anyone have any information about this species? IE. who it was made for, pressure levels or ballistics. I have Glock, Beretta & SIG full sized pistols but will use it primarily in my M&P 40 Compact. Any input would be appreciated.

I am not absolutely certain but I believe thst that is ammo that did not quite meet the specs called out in a contract to a law enforcement department. Still good ammo so they reclassify it and sell it at a discount.
Often various Police / Sherrif's departments (especially larger ones that buy a large amount of ammo) specify penetration / expansion parameters using standard calibrated ballistic geletin. The ammo company has to certify that it meets the parameters. Any that doesn't gets reclassified.

same thing with ammo boxes that say "not for law enforcement use". was designed for LEO's but for what ever reason,never made it to them. jwr