Choose the type of steel to be used for the gun barrel. The steel chosen must have a strength of 100,000 psi (689476 kPA) to withstand the force of the gasses that propel the round. The steel should have a hardness of 25 to 32 on the Rockwell scale so that the steel is strong enough to contain the pressure necessary to propel the round through the barrel, but not so brittle that it will be harmed by the machining operations to be performed.  Obtain rods from a specialty steel mill. Ask for a quality certification on the steel. Specify that the steel must be stress relieved at the steel mill.

• Select 4140 chrome moly steel. Chrome moly steel is the least expensive alternative. It also is easier to chemically blacken, if desired, to give a traditional look to the barrel.
• Decide on 416 stainless steel. Stainless steel is more expensive than chrome moly Steel. Stainless steel barrels have have a longer service life and are result in a more accurate firearm than do chrome moly steel barrels.

The idea of deep hole drilling emerged from its use for generating long and straight holes in the Guns and armaments industry. Defence industry is one of the major areas where deep hole drilling finds its application. The Barrel is the heart of the Gun and to obtain an accurate hole with the required surface finish is one of the precursors to a very accurate gunshot! Gun Barrel drilling is one of our specialties. Profidrill has supplied numerous deep hole drilling solutions to most Ordnance factories worldwide for drilling and finishing various types of barrels like Piston barrel, Rifle Barrel, Shotgun Barrel etc. Profidrill has developed specialty machines for operations like Rifling, Draw Boring, Pull Reaming, Honing and regularly services components like Torpedo tubes, actuator casing, breech block etc. specific for the defence industry.