Exactly where the mandrel is positioned the barrel blank will be forged by several hammers driven by the engine with huge power and velocity, until the steel touches the mandrel at its surface mirroring the grooves and lands on itself. The steel will be compressed, encreasing its strenght to about 10 to 25%. Milling the rear of chopper lumpsThe workman-ship results in a perfect bore, exactly straigth with truely shining face well resistant against deterioration from the elements. No further machining is required. This gives a well consistant precision to the barrel.
When specially required by customers or beeing not available the forging-mandrel for some calibers of rifled barrels they may be also made with traditional system with all the necessary working steps as: general leveling, makeready of the extremities for the drilling, drilling, reaming by three or four reamers depending from the caliber, cheking of the diameter thanks to plugging operation and visual control of the rough grade, passing through an ogive by pressing or by broaching or ruling machine, turning sleeving tubesfirst turning, exposition to controlled atmosphere when required by the caliber , refinishing turning.
Each one of the listed steps is followed by a leveling control. At the end of the working schedule barrels are exposed to an heat treating to spread the molecules and also exposed to a controlled atmosphere to bring the hardness over 90 KG.