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11/11/2015 10:02:02 PM EDT
I am writing a tech page to help newbies and other to understand or pick the parts for them ...
Here what I have so far and would like some input please.
Bolt Carrier Group-aka BCG

Bolt Metal

8620 steel
This grade of steel is mostly reserved for the carrier and has the weakest strength of all the steels ..To most people this shouldn't be used for a bolt cause of strength reason and over all safety.

158 Carpenter Steel
This steel for me is the absolute minimal that I would use for a bolt and the only steel that is MIL spec.

9310 Steel
This supposedly a minor upgrade to the 158 Carp steel and AIM claims to have less breakage with this steel vs 158 Carp..


Coating

Phosphate or Parkerizing
This the most basic and common coating and considered MIL spec .. The coating can be a little rough and hide some flaws in the workmanship.. It may take a couple rounds to smooth it out ..

Nitride  
This is not a coating  but a process  and it changes the outside steel like anodizing..The steel is now slicker and easier to clean with this process..Also cause it's not a coating the finished product must be a better  cause  the Nitride step will show every flaw or imperfection...

Nickle Boron Coating
This a coating applied to the metal similar to chrome ..This is the slickest coating of all and is easier to clean and supposedly can be ran without lube but I would still add lube cause it better to be safe than sorry later down the road..Remember though this a coating only and is  really not needed to run a AR platform but does look nice but it cost more for it and use will have to decide if it worth it to him or not...


Please be gentle
11/12/2015 4:01:42 AM EDT
[#1]

•HPT Bolt (High Pressure Tested/ Proof)
•MPI Bolt (Magnetic Particle Inspected)
•Shot Peened Bolt
•Chrome Lined Carrier
•Chrome Lined Gas Key
•Gas Key Hardened to USGI Specifications
•Grade 8 Hardened Fasteners
•Key Staked Per Mil-Spec
•Tool Steel Extractor
•Black Extractor Insert
•Mil-Spec Crane O-Ring
11/12/2015 9:21:36 AM EDT
[#2]
Nickel Teflon is slicker than nickel boron.
11/12/2015 9:41:03 AM EDT
[#3]
Is English your first language?



You left out Aeromet and S7 for bolt materials.



Aeromet is stronger than C158 or 9310.  AFAIK it's only used in the LMT E-bolt. Bolt life is indefinite.



S7 has been used by Sharps Rifle Co.  They have had heat treat issues that led to broken bolts.  Reportedly this steel has trouble in extremely low temperatures.
11/12/2015 9:54:58 AM EDT
[#4]
Quote History
Quoted:
Is English your first language?

You left out Aeromet and S7 for bolt materials.

Aeromet is stronger than C158 or 9310.  AFAIK it's only used in the LMT E-bolt. Bolt life is indefinite.

S7 has been used by Sharps Rifle Co.  They have had heat treat issues that led to broken bolts.  Reportedly this steel has trouble in extremely low temperatures.
View Quote


Sorry I was half asleep and had my screaming daughter ...
Ok and I am noob to this and looking for everyone helps for the best possible information... The Article will be for AR15.com
So any input would be greatly appreciated  
11/12/2015 9:57:14 AM EDT
[#5]
I understand, I've got two little ones myself with a third on the way
11/12/2015 10:11:19 AM EDT
[#6]
Quote History
Quoted:

•HPT Bolt (High Pressure Tested/ Proof)
•MPI Bolt (Magnetic Particle Inspected)
•Shot Peened Bolt
•Chrome Lined Carrier
•Chrome Lined Gas Key
•Gas Key Hardened to USGI Specifications
•Grade 8 Hardened Fasteners
•Key Staked Per Mil-Spec
•Tool Steel Extractor
•Black Extractor Insert
•Mil-Spec Crane O-Ring
View Quote

Proper gas key bolt staking
11/12/2015 11:16:01 AM EDT
[#7]
Quote History
Quoted:
Is English your first language?

You left out Aeromet and S7 for bolt materials.

Aeromet is stronger than C158 or 9310.  AFAIK it's only used in the LMT E-bolt. Bolt life is indefinite.

S7 has been used by Sharps Rifle Co.  They have had heat treat issues that led to broken bolts.  Reportedly this steel has trouble in extremely low temperatures.
View Quote

dont buy into hype, nothing lasts forever.. nothing.
11/12/2015 11:31:09 AM EDT
[#8]


Quote History
Quoted:





dont buy into hype, nothing lasts forever.. nothing.
View Quote View All Quotes
View All Quotes
Quote History
Quoted:



Quoted:

Is English your first language?



You left out Aeromet and S7 for bolt materials.



Aeromet is stronger than C158 or 9310. AFAIK it's only used in the LMT E-bolt. Bolt life is indefinite.



S7 has been used by Sharps Rifle Co. They have had heat treat issues that led to broken bolts. Reportedly this steel has trouble in extremely low temperatures.


dont buy into hype, nothing lasts forever.. nothing.


When ammo costs .20+ each and life is 60,000+ rounds, it's pretty close.  At that point your through multiple barrels on the same bolt.



FWIW, I get along fine with C158 and 9310.  Few of my rifles will burn a barrel out.
11/12/2015 12:47:15 PM EDT
[#9]
The last I saw AIM said they have had one CS158 bolt break.
Words matter; are you saying NiB is similar to chrome or that NiB is applied in a way that is similar to the way chrome is applied.
You also need to verify your facts.
11/12/2015 1:48:53 PM EDT
[#10]
Quote History
Quoted:


Sorry I was half asleep and had my screaming daughter ...
Ok and I am noob to this and looking for everyone helps for the best possible information... The Article will be for AR15.com
So any input would be greatly appreciated  
View Quote View All Quotes
View All Quotes
Quote History
Quoted:
Quoted:
Is English your first language?

You left out Aeromet and S7 for bolt materials.

Aeromet is stronger than C158 or 9310.  AFAIK it's only used in the LMT E-bolt. Bolt life is indefinite.

S7 has been used by Sharps Rifle Co.  They have had heat treat issues that led to broken bolts.  Reportedly this steel has trouble in extremely low temperatures.


Sorry I was half asleep and had my screaming daughter ...
Ok and I am noob to this and looking for everyone helps for the best possible information... The Article will be for AR15.com
So any input would be greatly appreciated  


I'll ask again.  Is english your first language?  Most of your sentences are incomplete and/or grammatically incorrect.  You should have someone proof your writing before you submit.  I can do it if you want.
11/16/2015 3:20:42 PM EDT
[#11]
Quote History
Quoted:


I'll ask again.  Is english your first language?  Most of your sentences are incomplete and/or grammatically incorrect.  You should have someone proof your writing before you submit.  I can do it if you want.
View Quote View All Quotes
View All Quotes
Quote History
Quoted:
Quoted:
Quoted:
Is English your first language?

You left out Aeromet and S7 for bolt materials.

Aeromet is stronger than C158 or 9310.  AFAIK it's only used in the LMT E-bolt. Bolt life is indefinite.

S7 has been used by Sharps Rifle Co.  They have had heat treat issues that led to broken bolts.  Reportedly this steel has trouble in extremely low temperatures.


Sorry I was half asleep and had my screaming daughter ...
Ok and I am noob to this and looking for everyone helps for the best possible information... The Article will be for AR15.com
So any input would be greatly appreciated  


I'll ask again.  Is english your first language?  Most of your sentences are incomplete and/or grammatically incorrect.  You should have someone proof your writing before you submit.  I can do it if you want.

Yes English is my first language ..
11/16/2015 3:25:06 PM EDT
[#12]
Tool Steel Extractor-
Do they make a lower quality ones ??? Is the Tool Steel an upgrade or just necessary???
Sorry I am looking for more information about the extractor, so any input would be greatly appreciated..
11/16/2015 3:29:29 PM EDT
[#13]


Quote History
Quoted:

Tool Steel Extractor-

Do they make a lower quality ones ??? Is the Tool Steel an upgrade or just necessary???

Sorry I am looking for more information about the extractor, so any input would be greatly appreciated..
View Quote


Lot's of places say Tool Steel, but they don't specify the type of Tool Steel.  Bryan from AIM is pretty helpful, so you might try asking him about the extractors they use and how they compare with other extractors.
11/16/2015 10:38:21 PM EDT
[#14]
Quote History
Quoted:

Lot's of places say Tool Steel, but they don't specify the type of Tool Steel.  Bryan from AIM is pretty helpful, so you might try asking him about the extractors they use and how they compare with other extractors.
View Quote View All Quotes
View All Quotes
Quote History
Quoted:
Quoted:
Tool Steel Extractor-
Do they make a lower quality ones ??? Is the Tool Steel an upgrade or just necessary???
Sorry I am looking for more information about the extractor, so any input would be greatly appreciated..

Lot's of places say Tool Steel, but they don't specify the type of Tool Steel.  Bryan from AIM is pretty helpful, so you might try asking him about the extractors they use and how they compare with other extractors.

Thanks I will have to check him out later and see if he can help out..
11/16/2015 10:55:54 PM EDT
[#15]
Quote History
Quoted:

•HPT Bolt (High Pressure Tested/ Proof)
•MPI Bolt (Magnetic Particle Inspected)
•Shot Peened Bolt
•Chrome Lined Carrier
•Chrome Lined Gas Key
•Gas Key Hardened to USGI Specifications
•Grade 8 Hardened Fasteners
•Key Staked Per Mil-Spec
•Tool Steel Extractor
•Black Extractor Insert
•Mil-Spec Crane O-Ring
View Quote


That's a good list.  
11/17/2015 12:08:53 AM EDT
[#16]
There are MIM extractors and gas keys and also ones machined from bar. Some advertise the MIM parts as "hardened to milspec" but some consider them to be less desirable. The MIM parts can be identified by the sprue or parting line.
11/17/2015 12:31:48 AM EDT
[#17]

Quote History
Quoted:


There are MIM extractors and gas keys and also ones machined from bar. Some advertise the MIM parts as "hardened to milspec" but some consider them to be less desirable. The MIM parts can be identified by the sprue or parting line.
View Quote
I believe some are cast as well.

 
11/18/2015 11:20:22 PM EDT
[#18]
Quote History
Quoted:
I believe some are cast as well.  
View Quote View All Quotes
View All Quotes
Quote History
Quoted:
Quoted:
There are MIM extractors and gas keys and also ones machined from bar. Some advertise the MIM parts as "hardened to milspec" but some consider them to be less desirable. The MIM parts can be identified by the sprue or parting line.
I believe some are cast as well.  

Right now I have a couple companies help me out with more and better information about the bcg and their experiences..

Oh what companies should make the list as far when buying a bcg??
11/18/2015 11:39:41 PM EDT
[#19]
Quote History
Quoted:

•HPT Bolt (High Pressure Tested/ Proof)
•MPI Bolt (Magnetic Particle Inspected)
•Shot Peened Bolt
•Chrome Lined Carrier
•Chrome Lined Gas Key
•Gas Key Hardened to USGI Specifications
•Grade 8 Hardened Fasteners ASTM A574 fasteners
•Key Staked Per Mil-Spec
•Tool Steel Extractor
•Black Extractor Insert
•Mil-Spec Crane O-Ring
View Quote

11/19/2015 12:34:58 AM EDT
[#20]
Quote History
Quoted:

View Quote View All Quotes
View All Quotes
Quote History
Quoted:
Quoted:

•HPT Bolt (High Pressure Tested/ Proof)
•MPI Bolt (Magnetic Particle Inspected)
•Shot Peened Bolt
•Chrome Lined Carrier
•Chrome Lined Gas Key
•Gas Key Hardened to USGI Specifications
•Grade 8 Hardened Fasteners ASTM A574 fasteners
•Key Staked Per Mil-Spec
•Tool Steel Extractor
•Black Extractor Insert
•Mil-Spec Crane O-Ring




Some people want to know what the difference is. Here http://store.curiousinventor.com/guides/screws/grades
11/19/2015 2:01:37 AM EDT
[#21]
Don't forget about the mil spec Permatex gasket sealer between the gas key and bolt carrier.
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