It is German short-range (sort of) training ammo. One online dealer had a deal a while back where you could get the special blowback-only, non-locking bolt for your G3 clone, allowing semi-auto operation with the blue plastic cased training ammo.
http://hkpro.com/forum/showthread.ph...-Training-Bolt
Some folks have indeed used them as varmint rounds, with good results, as long as the range is kept semi-reasonable.
They are very different from the PCA rounds, as they do not fire a traditional projectile... And they function properly for their intended use. No plastic casing-tubes stuck in the chamber.
