Cm and stainless barrels machined bare have about the same level of accuracy.
Chrome moly vs stainless steel ar 15.
Regular 4140 moly is just a regular barrel steel it will last a long long time with the most often used twist rate on one turn in 9 inches.
It has an advantage is it is less difficult to cut the rifling in the 4140 than harder 4150 which makes for slightly better accuracy in theory.
Stainless steel ar 15 barrels.
The name given by the society of automotive engineers sae usually follows the pattern 4xxx.
Chromium molybdenum specifically means a family of steel alloys that when used for hand tools have a moderate amount of carbon often around 0 4 to 0 5 around 1 chromium around 0 15 to 0 20 molybdenum and a range of other alloying elements.
When we start talking about stainless steel barrels everyone assumes we re talking about precision rifles and match grade barrels.
Some other manufacturers prefer to chrome line the inside of their ar barrels and some do not.
Some manufacturers prefer to use 4140 or 4150 steel while others prefer to use 416 ss or 416r steel for its properties.
First let s have a discussion about the chemical elements of each material and how their properties effect barrel life accuracy and cost.
Without the chrome they are finished a little more rough in.
Chrome moly or stainless steel.
Multiple steel types are used in the manufacture of the nbsp ar 15 barrel.
Steel is alloyed with other metals like nickel and chrome as well as other non metals such as carbon sulfur and silicon.