HM3... the 8mm German(rimless) is known here and the Portugese ammo we get in boxes or clips is berdan primed but clean and very good shooting ... the "JS" tag is not known, but may be modern type. There was a safety problem with early(WW1) 8mm mauser ammo in different diameters, I believe, so it may pay to check the new projectile to your barrel diameter. ***There are also ample stocks of 7.92X57R(rimmed) still available in Australia in big field-supply tins and dinky 10 round cardboard pouches/clipped for the M. `95 Steyr straight-pull carbine and rifle - made in Austria pre-war and with both the double eagle and Nazi swastica headstamps about 1935.***This may- (or not)- be a help!
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XXX the Bunny.
