In Denmark we have to use steel or bismuth shells because of lead ban. The shortest Eley bismuth shells are 67½ mm. Hence we get our old guns regulated to 70 mm chamberlenght, to decrease the chamberpressure. We do not use 70 mm or longer shells. The biggest store in Denmark (Hunters House) http://www.huntershouse.dk/kat183-Klassiske-våben/)decline to sell a gun with shorter chamberlength than 70 mm
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