German defence contractor Rheinmetall displayed 120mm and 130mm ammunition, signalling its interest in persuading European armies to adopt larger‑calibre tank guns. While manufacturers argue that new tanks can be retrofitted to accept a 130mm gun, opponents contend that modern 120mm rounds remain sufficient against current threats and that the larger calibre would increase cost, weight and reduce ammunition load.
No European country has yet committed to the upgrade, and the 130mm concept remains in the testing phase for next‑generation tanks.