Yes, a Greifeldt Model 500 with a proof date of 3(8)/28(26) but difficult to tell. The proofdate is adjacent to the S just ahead of the forward lug under the "57". 13 gram bullet weight for the cartridge. Is there a "Nitro" stamp on the sides of the scattergun tubes? The Model 500 had a crossbolt, sideclips, automatic pop-up sight when the solid projectile tube is selected, devoid of engraving & with either Krupp or Böhler tube steel.

Kind Regards,

Raimey
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