.22 caliber conversion units or sub-caliber adaptors were used on the Browning machine guns for troop training before and during World War II. The 3 variations of these Conversion Units were:
M3 for the 1917a1 M4 for the 1919a4 M5 for the ANM2 .30 caliber
After the war, they became obsolete and were sold for scrap. Today many of the original parts are still available, however there are many parts which have either very limited availability or are not available at all. At Belt Fed Plus we manufacture parts which fall into the catagory of limited availablity or not available at all. Since all our parts are made to original blue prints, we can help those who have some of the parts complete their own sub-calber adaptor. We can provide all parts from the belt adaptor clip to the bolt and the bolt either complete or stripped. If you have some of the parts and want to complete your .22 caliber unit you have come to the right place. Original blue prints are used for all our parts and all our parts will interchange with original parts.