158 Carpenter Steel Vs 9310

P-6 and 9310 are very close in composition. It is this variable that keeps me away from them in general although I do own one 9310 bolt w 8620 carrier as a back-up.

Bolt Carrier Only

What interested me was the bolt material.

158 carpenter steel vs 9310. 158 steel is the mil-spec steel used for fabricating the bolt itself. It is not totally out. Carpenter 158 is a casesurface hardened steel where 86209310 is through hardened.

Metallurgy has come a long way since and 9310 is a better metal for a bolt. This is the MIL-SPEC alloy used for the bolt. I tried 9310 AMS6260 not 6265 I see there is a considerable price difference over 7 a pound.

Caliber223 556 NATO 300 Blackout. I know 9310 alloy steel is very strong they make differential ring and pinion gears for professional class drag racing cars. 9310 or Carpenter 158 C158 Steel.

M16 Full Auto Style. I have been partial to the Carpenter 158 material for bolts but there are quite a few available in 9310. Dont know I barely made it through that class.

The Carpenter 158 has to be purchased in 20000 Lb lots and is roughly 5Lb. It has been the Mil-Spec since. 158 is controlled by Carpenter and you have minimum weight orders to meet or they will not sell to you.

C158 was specd in the 50s 60s. Get the cheaper one or the one with the rollmark that makes you feel warm and fuzzy. This is why I was thinking about A2 as it is about half as expensive and relatively cheap to heat-treat compared to the pricing for 40 case.

Typically the AR15 community looks for C-158 which is a blend of steel from Carpenter. I have both types of bolts and both work great. This was many years ago and many things change in metallurgy as new testing procedures and innovations come out.

Its Carpenters secret proprietary steel and if you want it you buy it from Carpenter. Since the creation of Carpenter 158 the metals industry has continued to innovate creating new blends of steels. Compared to modern alloys 158 is a very poor choice for carbine weapons failing in as little as 3000 rounds when pushed hard - 9310 is far superior in this respect.

Also since Carpenter has never made or tested any bolts using 9310 I fail to see how anything they say with regard to its use is of any relevance whatsoever. 9310 can be better than C-158 but it all depends on who does the heat treatment and how good it is. But the material that we are currently using is supplied to us by our customer.

This is an excellent steel alloy with high core hardness and fatigue strength. 8620 Steel Toolcraft Proprietary. Some say 9310 has a slight advantage over 158 but looking at the chemical makeup they are very similar.

IMO the heat treat is probably more important than the alloy comp. Posted July 20 2014. It is a product of the Carpenter steel company the sole maker and you wont find it on the SAE list although if you did it would probably be known as 3310.

I have had several other smaller firearms companys contact me looking to purchase these bolts. Case hardening allows C-158 to be very hard on the outside to prevent wear and crack formation while the inside is softer and more flexible to prevent crack propagation and absorb shock loads. More and more bolts are being made from it because of availability.

It has several alloy elements that promote a better structure and in the correct heat treatment will provide a slightly higher toughness than Carpenter 158 which is benificial to the fatigue life. The 9310 has some molybedenum while the P-6 has more chrome and nickel. 9310 is a AISI standard grade of tool steel that makes it about 7 stronger than mil-spec Carpenter 158 steels when appropriately treated.

9310 steel has higher tensile and yield strength than 8620 steel making it an excellent choice for bolt carrier construction. 9310 is about half the cost of P-6. We are currently making bolts for a very large AR-15 manufacturer.

Carpenter-158 is mil-spec. C-158 is simply Carpenters trade name for P-6 tool steel. What I surmised was that 9310 should be a better bolt material as long as it.

I believe 9310 steel is stronger than C158. This type of steel is more expensive than 9310 another popular steel used for the bolt and carrier but it provides the best performance and lifespan for the BCG. By comparison AISI 9310 will on first inspection also make an adequate bolt material.

All the high pressure bolts like JP Enterprises are made with 9310 and state its stronger than C158 which is just mil-spec the minimum standard. 9310 is a AISI grade of tool steel that is approximately 7 stronger than Carpenter 158 steel when heat treated and processed correctly. Its also replacing traditional 8620 and Carpenter 158 steel in many cases.

AR-15 bolts for instance are made of a steel known as Carpenter 158. 9310 is also a Carpenter product but the make up of the steel differs between the two. Theres been no extremely high round count testing to determine whether 158 or 9310 is better but both are considered to be better than 8620 but rest assured.

8 Best 300 Blackout Bolt Carrier Groups Bcg Acmen