Carpenter 158 Vs. 9310. Printable View. Show 40 post(s) from this thread on one page ... Originally Posted by SilverBullet432. You could have a bolt machined from a unicorn's horn. It may be better then the no. 158 bolt, but, its not mil-spec. Thats not what the TDP calls for. ... Aermet 100 is one material that seems to be clearly better than ...While the Nickel Boron on the 9310 steel bolt was chosen for being easy to clean, having a low coefficient of friction, AND with the benefit of heat dissipation. ... Carpenter 158 steel bolt; Chrome-lined interior bolt carrier key and bolt carrier; Torqued and staked gas key screws; Coated with a matte black mil-spec finish;Can somebody tell me what the difference is between c-158 and 9310 and why 9310 isn't mil-spec? I've seen 9310 used in some bolts and wonder if it's actually inferior. Is there technical data to show that c-158 is superior?This bolt carrier is manufactured from case hardened 8620 steel with properly staked 4130 steel gas key. The accompanying bolt is Carpenter 158, shot peened, HPT and MPI tested, and finished in a self-lubricating polished black nitride. Bolt lugs are CNC ground following heat treatment to insure the greatest accuracy possible.Click The Button Below To Learn More About The Toolcraft 5.56 Phosphate MPI Full-Auto BCG - No Logo (Over 195 Reviews!): 3. Toolcraft Nitride Full-Auto BCG (w/ Logo & Carpenter 158 Bolt) Number 3 on this list of fantastic BCGs is the Toolcraft Nitride Full Auto BCG, and there are a number of reasons why I like it.Firearm Discussion and Resources from AR-15, AK-47, Handguns and more! Buy, Sell, and Trade your Firearms and Gear.Proudly made in the U.S.A. This will also come with an engraved AR-308 Dust Cover w/ Customer Choice of Engraving! 308 Nitride Bolt Carrier Group BCG Nitride 308 Bolt Carrier Group (BCG) Product Specs: 308 Caliber Salt bath nitride finish M16 cut 9310 steel carrier Carpenter 158 steel bolt 4140 steel extractor MIL-SPEC O-ring MIL-SPEC gas rings ...See how we test. The $949.99 base model of the XPS 13 has a Core i3 CPU, 8GB of memory, a 256GB solid-state drive, and a 1,920-by-1,200-pixel non-touch screen. It's silver with a black interior ...Jul 25, 2009 · Carpenter Technologies' 158 blend of steel was selected as it provided adequate strength and wear characteristics. It has been the "Mil-Spec" since. Since the creation of Carpenter 158, the metals industry has continued to innovate, creating new blends of steels. 9310 is a AISI standard grade of tool steel that makes it about ~7% stronger than ...One of the main differences between these two materials is their composition. S7 tool steel contains higher carbon and chromium levels, with higher hardness and wear resistance. 9310, however, has a lower carbon content but contains nickel, which gives it higher toughness and fatigue strength.While 9310 Tool Steel and Carpenter Steel have exceptional properties, they also have weaknesses. 9310 Tool Steel is known to be brittle at room temperature, while Carpenter Steel has a lower resistance to corrosion and oxidation. ... PREVIOUS Previous post: 9310 vs 158 Steel - What's the Difference. NEXT Next post: Aluminium 2007 vs 7075 ...The interesting thing about Carpenter 158 is that it is a proprietary steel alloy and its formula and method of manufacturing are not publicly defined. Therefore, there is no SAE standard for it and the sole manufacturer of this steel is a company called Carpenter Technology in Pennsylvania. ... In general, bolts made of 9310 steel are the ...We also offer the Toolcraft DLC BCG with a 9310 grade tool steel bolt. This bolt steel is 7% stronger than even Carpenter 158 steel. Above: SpiceTac specifies MIL SPEC Carpenter 158 steel for the bolts in our Diamond DLC BCGs. Even great bolt steels like 9310 and C-158 won't overcome one weakness that the AR-15 has shown over the years as it ...Which is better 9310 steel or Carpenter 158? It has been the "Mil-Spec" since. Since the creation of Carpenter 158, the metals industry has continued to innovate, creating new blends of steels. 9310 is a AISI standard grade of tool steel that makes it about ~7% stronger than "mil-spec" Carpenter 158 steels, when appropriately treated.Carpenter 158 is a chrome-nickel alloy steel with an analysis representing the best case hardening steel known for parts subject to heavy shock and wear. This alloy is ideally …5.56 Bolt is machined from Carpenter 158 tool steel; Shot peened; HPT tested/MPI marked; Black o-ring insert on extractor ... Nickel Bolt Carrier Group: No Aero 'A' Logo; Machined from 8620 Tool Steel (Carrier) and 9310 Steel (Bolt) Carrier has forward assist serrations; Shrouded firing pin; Nickel Boron Coating inside and out (Bolt, Carrier ...If fact, 9310 response to thin section quenching is better that Carpenter 158. And, taking the leap between this statement:". . . by comparison to Carpenter 158, AISI 9310 has several elements present in its composition that are detrimental to fatigue while not being evident in the physical properties . . ." and this statement:May 29, 2022 · Why 9310 Steel in an AR-15 / M16 Bolt? Why is 9310 Steel the superior option for your AR-15/M16 Bolt? Well, 9310 is actually around 7% stronger than Carpenter 158 and is better than "mil-spec." faxonfirearms.com. 9.The high alloy content in 9310 allows for heavy sections to be treated to result in high case hardness and high core strength and toughness. This material is useful without carburizing, yet carburizing produces a highly wear-resistant case. The material is vacuum degassed and is also available in consumable electrode vacuum remelting process.I've actually had a friend's PSA "Premium" BCG cause 100% malfunctions on his factory LMT 10.5" upper. We slapped in a BCM BCG and the failures went away.You are comparing the cost of the raw material with the cost of the finished bolt. I doubt it takes anywhere near a pound of steel to come out with a 3 or so ounce finished bolt. If it takes a third of a pound, that is still only $10 in the cost of a $50+ Bolt.Target said: I read an article by Faxon ( manufacturer of barrels and other parts) and they claim that 9310 steel is better than Carpenter 158. C158 is MilSpec and at the time. a good steel. 9310 is newer and 7% better. Faxon has a good reputation for barrels. so I will take their word on this.7.62 x 39 Complete Bolt Carrier Group Made in the USA Black Nitride Finish Made from Bolt 9310 Steel and Carrier 8620 Steel Works with AR15 Milspec Uppers $139.95. Add to Cart ... LOSOK CUSTOM ARMS .308 BOLT CARRIER GROUP For AR-10/LR-308 rifles 158 Carpenter Steel Bolt with Nickel Boron Finish 8620 Steel Carrier with Black Phosphate Finish ...All Toolcraft BCG bolts are shot-peened, MPI and batch HPT to ensure quality and reliability. Made from either mil-spec Carpenter 158 steel or high strength 9310 steel, bolt carrier groups from Toolcraft are guaranteed to perform like new for thousands and thousands of rounds. You cannot buy a better bolt carrier group than a Toolcraft.For material, Carpenter 158/C-158 is great and practically a standard. 9310 is a bit better (~5% harder than c-158 iirc), but apparently it is harder to do correctly because it has a narrower production temperature. ... Personally I prefer Carpenter 158 steel, but 9310 is probably fine too. All mine happen to be PSA Premium, but I would not ...Firearm Discussion and Resources from AR-15, AK-47, Handguns and more! Buy, Sell, and Trade your Firearms and Gear.Description. FULL AUTO RATED M16 / AR15 NITRIDE BCG ( Check it out ) BCG Includes: High Pressure Tested (HPT) Magnetic Particle Inspected (MPI) Carrier machined from 8620 alloy, full auto profile, heat treated, Nitrided. Gas Key machined from 4130 chromoly steel alloy, heat treated and Nitrided. Bolt precision machined from 9310 alloy ...Material: 8620 steel, coated Gas key: hardened billet 4140 machined, coated Gas Key Screws: Grade 8 properly staked (heavy strike) Coating: Ion Bond (DLC Tribo-41) coating 1,4. Bolt Subassembly: Material: Carpenter No. 158 Alloy Steel, Shot Peened MPI: Yes, MPI Inspected 2 Extractor: 4140 Heat Treated & Shot Peened O-Ring: Mil-Spec materialToolcraft BCGs are generally available with bolts made from either 9310 or Carpenter 158 steel. They are batch High Pressure Tested (HPT) and every bolt is Magnetic Particle Inspected (MPI). Markings on the bolts vary with some being marked MP or MPI and some being marked 9310 or C158.The bolt is CNC machined from heavy duty 9310 alloy steel. 9310 steel has a high core & fatigue strength rating, a high hardenability rating, and when properly treated it is actually about 7% stronger than the "mil-spec" Carpenter 158 steel. The bolt is shot peened (stress relieved) and finished with the same Nickel Boron finish as the carrier.C158 is supposed to technically be stronger than 9310, but many higher end BCG makers are now using 9310 instead of C158 for their bolts b/c they say 158 is antiquated and they have figured out how to make 9310 better than "mil-spec." Faxon uses 9310 in their bolts and so does Noveske. Aero precision and Brownells, which are more budget ...140-280. 1.20. Zr-0.0C1%Hf (Grade 21) Zircaloy 2 (Grade 32) Zircaloy 4 (Grade 34) Have a look at our machinability rating graph which without a doubt will make your decision a lot easier with its incredibly detailed information.8740 steel firing pin with hard chrome finish. Magnetic particle inspected. Proudly made in the U.S.A. 6.5 Gendel Nitride Bolt Carrier Group (Type II) BCG Nitride 6.5 Grendel (Type II) Bolt Carrier Group (BCG) Product Specs: 6.5 Grendel Salt bath nitride finish M16 cut 9310 steel carrier Carpenter 158 steel bolt 4140 steel extractor MIL-SPEC O-ri.Firearm Discussion and Resources from AR-15, AK-47, Handguns and more! Buy, Sell, and Trade your Firearms and Gear.7.62 x 39 Complete Bolt Carrier Group Made in the USA Black Nitride Finish Made from Bolt 9310 Steel and Carrier 8620 Steel Works with AR15 Milspec Uppers $139.95. Add to Cart ... LOSOK CUSTOM ARMS .308 BOLT CARRIER GROUP For AR-10/LR-308 rifles 158 Carpenter Steel Bolt with Nickel Boron Finish 8620 Steel Carrier with Black Phosphate Finish ...Firearm Discussion and Resources from AR-15, AK-47, Handguns and more! Buy, Sell, and Trade your Firearms and Gear.Ahhh...the 9310 vs 158. 158 and 9310 are similar in qualities. You can look at is as replacements for each other. No huge advantage with one ...The high alloy content in 9310 allows for heavy sections to be treated to result in high case hardness and high core strength and toughness. This material is useful without carburizing, yet carburizing produces a highly wear-resistant case. The material is vacuum degassed and is also available in consumable electrode vacuum remelting process.Firearm Discussion and Resources from AR-15, AK-47, Handguns and more! Buy, Sell, and Trade your Firearms and Gear.Apr 10, 2024 · This Toolcraft DLC Bolt Carrier Group comes complete with a 9310 grade tool steel bolt. This bolt steel is 7% stronger than commonly used "mil-spec" Carpenter 158 steel. This tougher than mil-spec bolt, when paired with Toolcraft quality and the Ionbond DLC finish is quite likely the ultimate hard use bolt carrier group!I bought one thinking it had a Carpenter 158 bolt according to the product description. The bolt I received is marked MPI 9310. The have subsequently changed the description to Carpenter No. 9310 steel. They claim the extractor is tool steel machined, however it and the gas key appear to be MIM.9310 is a premium quality alloy carburizing steel, containing nickel, chromium and molybdenum. It has a high hardenability, high core hardness and high fatigue strength, all of which make it ideally suited for critical aircraft engine gears, automotive applications, structural components, gears, rods, heat-treatable shafts, high performance helicopter …Better Bolt metal 9310 Steel or Carpenter 158 AR15 COM. The market demands 4150 because it is believes to be so much better than 4140 when in actuality they are nearly identical C 158 is simply Carpenters trade name for P 6 tool steel P 6 and 9310 are very close in composition The 9310 has some molybedenum while the P 6 has more chrome …Perhaps this is the wrong outlet to make this question, but can anyone tell me the difference in reliability and longevity between a bolt made from 9310 steel and Carpenter 158 steel? Does one resist shearing better but is more brittle, I assume something along those lines is the difference.IIRC, the original specifications for the GI issue model were for AQ-9310 (aircraft quality). The bolts were supposed to be good for 75K rounds, ... I use this company for my Carpenter 158 steels industrial metal sales it is moderatly priced and they ship quick give em a try ! T. truckeic Plastic. Joined Sep 12, 2017. Sep 3, 2019semi_cop. I think 9310 has more molybdenum and C-158 and P-6 machine steel is the same and has more nickel and chrome. I think C-158 has to be bought in larger bulk quantities than 9310 which has also led to more 9310 offerings. From what I understand if done right 9310 is more durable. I think all my bolts are 9310 except one in a COLT 5.56 gun.Firing Pin: Mil Spec firing pin made of 8740 steel, center-less ground and Hard Chrome coated Bolt Assembly: The Bolt is "true" Mil Spec dimension and external surfaces are CNC ground after heat treat for a precision fit. Material: Case Hardened 9310 Steel. Carpenter 158 is available for an additional charge.Stick with a C158 phosphate BCG from any reputable brand. If you want it to be slightly easier to clean then get a chrome one or an NP3 from Sionics. Avoid nitride ( especially if it comes with a 9310 bolt), NiB, TiN, and most other wiz-piss finishes. DLC isn't that bad but it's still not as good as a phosphate carrier with a chrome-lined bore. 3.Bolt Steel Carpenter No 158 Steel Profile Full Auto Profile Gas Key Grade 8 Hardened Fasteners Staked per MilSpec Features This Toolcraft Logod Nitride BCG is made with a carpenter 158 bolt with a full auto profile designed to be used in AR 15 M 16 style rifles. AR 15 BOLT CARRIER GROUP BrownellsWhat is the difference between a 158 carpenter bolt and one made from 9310 steel? The difference is in the steel. Many manufacturers will state that properly heat treated 9310 is approximately 7-8% "stronger" than 158, but 9310 requires that it be heat treated properly to achieve that increase in strength.Business, Economics, and Finance. GameStop Moderna Pfizer Johnson & Johnson AstraZeneca Walgreens Best Buy Novavax SpaceX Tesla. CryptoBrownells TiN Lightweight BCG. Their bolt uses 9310 steel, but again…it is likely never going to matter and is the standard for lightweight builds. It weighs in a little heavier than the Titanium counterparts at 8.2 ounces but is less than half the price. Brownells TiN Lightweight BCG, Rear.Now the bolts, they are made with AISI 9310 Steel, 9310 is better suited for an application such as a M16 bolt. 9310 is a steel typically used for gears, cams and things of that nature while Carpenter 158 or P6 tool steel is a plastic injection mold steel. 9310 is easier to machine and is more dimensionally stable in the heat treat process, this equates to …Description CarTech No. 158 alloy is a chrome-nickel alloy steel with an analysis representing the best case hardening steel known for parts subject to heavy shock and wear. This alloy is ideally suited for jobs where an extra measure of core strength is required. Fully treated, CarTech No. 158 alloy attains a core strength of approximately 160 ...IIRC, the original specifications for the GI issue model were for AQ-9310 (aircraft quality). The bolts were supposed to be good for 75K rounds, ... I use this company for my Carpenter 158 steels industrial metal sales it is moderatly priced and they ship quick give em a try ! T. truckeic Plastic. Joined Sep 12, 2017. Sep 3, 2019The carrier is made of AISI 8620 aircraft-quality steel, the Carpenter Technology No. 158 Alloy is used for the bolt, and the gas key is made from 4130 Chromoly steel. ... The bolt on this one is made from case-hardened 9310 steel which has been shot-peened and magnetic particle inspected for maximum durability and reliability.Toughness of over 200 ft./lb. Charpy C-Notch. HRC of 46 yields a 15% increase in hardness at the same toughness comparing to Carpenter 158 & 9310. Mil-Spec Extractor and Ejector Springs, Gas Rings. While the two bolts have identical construction, the two coatings vary slightly.8620 Steel carrier; Carpenter 158 steel bolt; 9310 steel extractor and cam pin; Compatible with 5.56, .223, and .300 BLK; Every component of this Nitride bolt carrier group needs to be made from materials suited for its role. The carrier needs to withstand high amounts of friction, so it was made from 8620 steel because it is more easily ..."Customers want modern designs, but the traditional stores do not offer that variety" The way Indians buy furniture seems to be changing. Until a few years ago, most would either c...Stick with a C158 phosphate BCG from any reputable brand. If you want it to be slightly easier to clean then get a chrome one or an NP3 from Sionics. Avoid nitride ( especially if it comes with a 9310 bolt), NiB, TiN, and most other wiz-piss finishes. DLC isn't that bad but it's still not as good as a phosphate carrier with a chrome-lined bore. 3.9310 VAR AMS 6265 is a Chromium-Nickel-Molybdenum Alloy used as a Carburizing Grade for Aircraft Parts. Users can obtain high case hardness coupled with high core strength and toughness. High alloy content makes it suitable for use in relatively large cross-sections. Its combination of high alloy and low carbon content can achieve high core ...Description CarTech No. 158 alloy is a chrome-nickel alloy steel with an analysis representing the best case hardening steel known for parts subject to heavy shock and wear. This alloy is ideally suited for jobs where an extra measure of core strength is required. Fully treated, CarTech No. 158 alloy attains a core strength of approximately …Aug 28, 2016 ... The most common steel used in the bolt is Carpenter 158 steel. Some manufactures are using 9310 steel. Which is better? It depends who you ...9310 Steel Round Bar is a nickel-chromium-molybdenum carburizing steel. With high hardenability, good core strength and fatigue resistance 9310 round bar is good in many aerospace applications as well as industrial and other forms of transportation. 9310 can come in a couple different variations and ams specs such as AMS 6265 and AMS 6260. In ...Firearm Discussion and Resources from AR-15, AK-47, Handguns and more! Buy, Sell, and Trade your Firearms and Gear.Apr 16, 2018 ... Budget Vs. Expensive! BCG's. KB32 Tactical•103K views · 14:24 · Go to ... PSA 5.56 NATO 9310 BASIC Bolt Carrier Group Full Review. KB32 Tactical&...What Is the Difference Between 9310 Steel and Carpenter 158 Steel? 9310 steel and Carpenter 158 steel differ in their composition and intended applications. …The difference is in the steel. Many manufacturers will state that properly heat treated 9310 is approximately 7-8% "stronger" than 158, but 9310 requires that it be heat treated properly to achieve that increase in strength. Carpenter 158 is mil-spec, but many companies nowadays are opting for "stronger" steels like 9310 and S7 which are both ...Fully treated, Carpenter 158 attains a core strength of approximately 160 ksi (1103 MPa) tensile strength with a yield point of approximately 135 ksi (931 MPa). These high mechanical properties are developed in sections up to 5" (127 mm) thick, making Carpenter 158 a consideration for use in very large parts requiring maximum strength, wear ...Bren. 79807 posts · Joined 2005. #2 · Aug 21, 2019. I looked at a couple of PSA kits recently and the only difference was that one had a 9310 bolt and one had a C158. I doubt it makes any difference, but the C158 is the mil spec, so it has been tried and tested a lot more for a lot longer, so I went with that. The left are a coalition of ...Bolt Material : Carpenter 158+ Carrier Material : 8620 Steel Coating : Nanoweapon MPI & HPT : Yes Full-Auto Rated : Yes. My Take. This is the most expensive option on this list. However, if there was ever a piece of equipment to spend a little more money it is the BCG. The Geissele BCG is the best on the market in my opinion.Bolt Material : Carpenter 158+ Carrier Material : 8620 Steel Coating : Nanoweapon MPI & HPT : Yes Full-Auto Rated : Yes. My Take. This is the most expensive option on this list. However, if there was ever a piece of equipment to spend a little more money it is the BCG. The Geissele BCG is the best on the market in my opinion.5.56 Bolt is machined from Carpenter 158 tool steel; Shot peened; HPT tested/MPI marked; Black o-ring insert on extractor ... Nickel Bolt Carrier Group: No Aero 'A' Logo; Machined from 8620 Tool Steel (Carrier) and 9310 Steel (Bolt) Carrier has forward assist serrations; Shrouded firing pin; Nickel Boron Coating inside and out (Bolt, Carrier ...MSRP: $139.99. Price: $119.00. — You save $20.99. Quantity: Add to Wish List. Description. Additional Information. This bolt carrier is manufactured from case hardened 8620 steel with properly staked 4130 steel gas key. The accompanying bolt is Carpenter 158, shot peened, HPT and MPI tested, and finished in a self-lubricating polished black ...This premium backup bolt is a 9310 MPI spare bolt that perfectly fits the M16 and AR15 carriers and has a black nitride finish that provides increased corrosion resistance, natural lubrication and improved strength. When comparing 9310 vs 158 bolts, 9310 steel bolts provide a more reliable and durable base metal.c158 is carpenter 158 meaning only carpenter can supply the stock so it's held to their standards. many years back after a mass shooting there was a run on parts including bcgs and manufacturers couldn't get c158 in a steady enough supply so they looked at alternative metals including 9310. on paper 9310 is stronger when heat treated correct, but given the rush of production that wasn't always ...Is steel still the best material for building? Learn about the pros and cons of using steel for building construction and engineering at HowStuffWorks. Advertisement Ever since the...8740 steel firing pin with hard chrome finish. Magnetic particle inspected. Proudly made in the U.S.A. 6.5 Gendel Nitride Bolt Carrier Group (Type II) BCG Nitride 6.5 Grendel (Type II) Bolt Carrier Group (BCG) Product Specs: 6.5 Grendel Salt bath nitride finish M16 cut 9310 steel carrier Carpenter 158 steel bolt 4140 steel extractor MIL-SPEC O-ri.Can somebody tell me what the difference is between c-158 and 9310 and why 9310 isn't mil-spec? I've seen 9310 used in some bolts and wonder if it's actually inferior. Is there technical data to show that c-158 is superior?8620 V/S 9310 V/S Carpenter 158 V/S S7 Steel: 8620 (normalized) is MIL-SPEC (MIL-S-16794) alloy used to machine the bolt carrier. Tensile Strength: 640 MPa Yield Strength: 360 MPa 9310 (normalized). 9310 is 10% less harder than the 158. Tensile Strength: 910 MPa Yield Strength: 570 MPa Carpenter 158. This is the MIL-SPEC alloy used for the bolt.Bolt Material: Machined from Mag Particle Inspected Carpenter 158 or 9310 Steel. Barrel: 18" Fluted Medium Profile, Chrome Lined with A2 Flash Suppressor. Barrel Material: 4150M Chrome Moly Vanadium 11595E Steel. Rifling: 1 Turn in 10" - Right Hand Twist - 6 Lands & Grooves.In the case of the M16 family, the US military selected a steel called Carpenter 158 (also known as "C158" or "Car 158") to be used for manufacturing the bolt. Therefore, any AR15 or M16 bolts that claim to follow military specifications (or "mil-spec" for short) should be made of C158 steel as one of the requirements.Aug 21, 2019 · Bren. 79807 posts · Joined 2005. #2 · Aug 21, 2019. I looked at a couple of PSA kits recently and the only difference was that one had a 9310 bolt and one had a C158. I doubt it makes any difference, but the C158 is the mil spec, so it has been tried and tested a lot more for a lot longer, so I went with that. The left are a coalition of ...Here's the info of my current BCG: Bolt Steel: Carpenter 158, Nickel Boron Bolt Carrier Profile: Full-auto It runs fine. I have had no issues with malfunctions. ... switched over to using 9310 steel. 9310 is slightly stronger than C158, much easier to heat treat to the desired toughness well, and because of that, slightly cheaper as well. 9310 ...Why 9310 Steel in an AR-15 / M16 Bolt? Why is 9310 Steel the superior option for your AR-15/M16 Bolt? Well, 9310 is actually around 7% stronger than …The NBS .223/5.56 Black Nitride Bolt Carrier Group was designed with strength in mind. Starting with , 9310, and Carpenters 158, are two distinct different types of steels. Both made for different kinds of applicat, Fully treated, Carpenter 158 attains a core strength of approximately 160 ksi (1103, Firearm Discussion and Resources from AR-15, AK-47, Handguns a, Grade 6 titanium belongs to the titanium alloys classification, while SAE-AISI 9310 s, It also exhibits good strength, high toughness, hardenability, core strength, and very h, The high alloy content in 9310 allows for heavy sections to be treated to result in high case har, Carpenter 158 Melonite / Nitride M16 Ar15 Bolt Carrier Group. $ 260, Fit: Semi-Auto or Full Auto AR-15/M16 (.223 or 5.56mm NATO) M, AISI E9310 Steel, single quenched and tempered at 23, Carpenter 158, on the other hand, contains a high percentage, C158 minus proprietary source + molybdenum = 9310, a sli, Carpenter 158 steel. Carpenter 158 steel can conti, Another difference is the strength and toughness le, Choose from either the very popular 9310 steel or the mil-spec 158 , Additional information. Reviews (1) Custom Engraved AR-15 5.56 Bol, What is the difference between Carpenter 158 and 9310 steel, We are a global leader in high-performance specialty alloy-base.