From http://www.doublegunshop.com/forums/ubbt...ge=4#Post135688 your right barrel is marked 18.4 which is the standard Belgian 12g bore size of .724" (US usually .729") and likely cylinder or no choke constriction. Your left barrel is marked 18.3 which is .7205", or a constriction of only .0035" or about skeet. Odd in that lots of Belgian guns are choked cylinder and full. BUT the barrels could have been honed or choke reamed since 1951 so the only way to know is to measure both the bore and the choke constriction.

Last edited by revdocdrew; 02/15/09 12:12 PM.
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