DEMIBLOC BARREL
The term demibloc is connected to the production of exclusive shotguns in England and Belgium, starting from the mid-nineteenth century to the mid-twentieth century. Demibloc barrel is a system for joining together the two demibloc pieces, either O/U and S/S. The production of demibloc barrels includes several operations which require specific skills. Currently CNC machine are utilized, but some operations need to be handmade.
Materials
The most popular type of steel used to produce both sleeving demibloc and rifle demibloc is 42CrMo4, hardened at ca 95/100 Kg/mm2. Barrels made with this steel can be used without chrome treatment. The customer can request a material document or a heat-treatment document.
Production phases
The raw barrel is first forged to create the bulge where half of the lumb will be obtained. Secondly the barrel undergoes several heat-treatment processes to enhance the mechanical characteristics of demibloc. Then the barrel is deeply pierced. Later, the barrel is rough-cut and finished with the lathe, which is followed by a grinding process. The next phase requires soldering two halfs together.
The semifinished product can be refined internally following customer’s requests. Throughout the several phases of production the barrel is straightened manually using the technique of the retta d’ombra. Currently Lamec srl is one of the biggest producer of demibloc barrel, created for the most important companies in the field. Lamec srl production include over/under and side by side barrels, which are built in bore 12, bore 16, bore 20, bore 28 and bore 410. Lamec srl even produces trilling barrels.During the construction demibloc barrels can be customized on customer’s request.