Side by side combination guns are nowadays quite rare but there still exists some older weapons in Europe, usually with smaller rifle caliber (mostly 7 mm or .30 cal) than real "cape guns".

There is many different compos among drillings; most usual is that version which Daryl S just describes but there is too bock-drilling, an O/U Rifle-shotgun combination with a smaller caliber rifle-barrel on the side. Then there is double rifle drilling, as name says, double rifle with one shotgun barrel.