...just to shoot it up...
If I had a few K of this 8MM,I'd clip a few coils off the firing pin spring of 1-8MM rifle...one only...and make that ammo shootable. OR...try it in a 1919 belt fed...just to see if it can be fired. If no joy...pull the bullets,save the powder and verify the grains loaded. Then use in reloading boxer-primed cases.