Hard Core Records was a DIY label. It managed one singles a single by Untamed Youth, 'Running Wild' (HAR-001) seems to have been the only release on the Hard Core label.  It came out in 1979. which looks like a French pressing.  Quite a few British singles from small independent companies were pressed in France around this time, presumably for reasons of cost or availability.  They tend to be injection moulded, and they have a different appearance to British injection mouldings.  See Absurd, Rabid and SRS for other examples. Distributed By Hard Core Records. Thanks to Robert Lyons For The Info.

79 Untamed Youth  Running Wild HARD CORE HAR 001