Unknown 13 mm case

[Hoeksel]

Can anybody shed some light on the shown case? It measures (hard to measure correctly) ~ 13x133R22 mm. No visible head stamp.

 

[Hoeksel]

Does anybody recognize this case?

Some more details: It measures 13x133.3R22.1 (doubt about the actual caliber, could be between 12.5 and 13.5 mm)

Rim thickness 2.7mm
Distance between rim and case body 3.0mm
Case body length 111.0mm
Case neck length 15.0mm

 

[Tony Williams]

I can't imagine that such a case would be used in anything other than an anti-tank rifle, but what type I don't know!

 

[Hoeksel]

Indeed. It was listed as a 13mm Czech experimental anti-tank rifle according the seller.