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alamo5000
10 July 2015, 22:33
I am currently running a BCG from Rainier Arms.

The one I run is here:

http://www.rainierarms.com/rainier-arms-bcg-phosphate

I was recently looking around and I saw that Rainier also offers this one:

http://www.rainierarms.com/rainier-arms-precision-match-grade-phosphate-bcg

Realistically what is the difference between the two? Would I see any performance upgrade by going with the latter?

What's the deal between these two? Why is one "Match" and the other not?

I am very pleased with what I am using now... but if there is something to be gained by upgrading I would like to know what it would be.

mustangfreek
11 July 2015, 02:33
Hummm just noticed these also not too long ago

Appears at a quick glance and not truly knowing, the radius/angle cut better design, stamped vs (asuming billet stock) extractor and maybe gas key also?

im not totally sure, assuming someone will correct me or whatnot

GOST
11 July 2015, 02:52
The difference between the two is the profile and additional mass of the latter is supposed to allow a more consistent bolt lock up. Some newer BCG's also have a slightly flared tail on the carrier that also supposed to increase this. I have no experience in how much this helps though and have had great luck with regular FA profiled carriers. If you're not currently having issues I wouldn't change out the BCG.

alamo5000
11 July 2015, 06:47
If you're not currently having issues I wouldn't change out the BCG.

If it ain't broke... LOL:P

I am more than pleased with what I have now. For sure. That said I think I am going to start buying parts starting with things that are 'wear out' or 'break down' parts... those parts will eventually turn into another rifle but I am ok with that. [BD]

UWone77
11 July 2015, 20:09
Realistically what is the difference between the two? Would I see any performance upgrade by going with the latter?

What's the deal between these two? Why is one "Match" and the other not?

I am very pleased with what I am using now... but if there is something to be gained by upgrading I would like to know what it would be.

Realistically, the difference you'll sell between the two is one will remove a few more dollars from your account. Actual range use? I doubt you'd see any difference or a quantifiable difference. Both run, if you like the looks of the other vs the next, go for it as your wallet allows.

alamo5000
11 July 2015, 20:32
Realistically, the difference you'll sell between the two is one will remove a few more dollars from your account. Actual range use? I doubt you'd see any difference or a quantifiable difference. Both run, if you like the looks of the other vs the next, go for it as your wallet allows.

I was thinking the same thing but I didn't know for sure so I didn't want to say it LOL!

As I said before, I'm very pleased with what I have now. I am not big on coatings and low mass or any of that other jive. I think what I have is good enough so I don't know how it would "fix" anything or do anything really that much better.

All that said I see BCGs priced all over the place. Other than the basics of using good material, proper staking, etc I'm not really sure how to separate out the so so ones from the top tier or at least the better ones.

GOST
11 July 2015, 21:00
The Fathom enhanced BCG is getting great reviews. I'm not sure if they are made by the same company, but the BCG in the new Hodge AU-MOD 2 and the one in Erathr3's rifle look like rebranded Fathom enhanced BCG's.

UWone77
11 July 2015, 21:01
For the same money, I think the standard Fathom carrier is where it's at. Obviously, I'm a big fan of Rainier, but the nitride coating is really winning me over.

alamo5000
11 July 2015, 21:14
For the same money, I think the standard Fathom carrier is where it's at. Obviously, I'm a big fan of Rainier, but the nitride coating is really winning me over.

What's the deal with the nitride coating? What is better about that than say phosphate?

I'm really just picking ya'lls brains some because I don't know what's special about coatings of almost any kind when it boils right down to performance.

That said I pretty much don't consider many things until they pass the WEVO test. I guess I just go straight for the top shelf LOL. That's mainly because I don't want the hassle of sub par stuff (maybe I'm spoiled in a way...I don't know), but buy good once, cry once...buy crap and cry a lot.

GOST
11 July 2015, 21:37
Nitride coating is actually a surface treatment that is actually bonded into the surface of the carrier rather than just a coating, it is harder and slicker than both NiB and phosphate coatings.

alamo5000
11 July 2015, 21:49
Nitride coating is actually a surface treatment that is actually bonded into the surface of the carrier rather than just a coating, it is harder and slicker than both NiB and phosphate coatings.

I know they nitride barrels. I assume it's the same treatment? If so I wouldn't really classify that as a "coating" per se. I don't know but there could be virtue in that. I don't know what the end result is by doing that to a BCG.

If the surface of the metal is physically harder though that's a difference that I need to think over.

GOST
11 July 2015, 22:13
There was a thread where DutyUse did a torture test on the Fathom Arms Enhanced BCG without lube. In his review he showed pics where the black nitride treatment had rubbed off. Fathom responded and said that the nitride treatment was still in place because it wasn't a coating, that it actually bonded into the metal. Fathom stated how deep the treatment actually goes but I don't remember the actual depth. You can take a 1911 slide that has had a nitride treatment and polish the surface away to it appears to be black chrome.

GOST
11 July 2015, 22:22
If nothing else the nitride treatment has minimal growth unlike coatings which allows more control of tolerances.

SINNER
12 July 2015, 00:24
Black Nitride is a brand name for Ferritic Nitrocarburizing. It's also known as Melonite, tennifer, or QPQ. Basically it's a process where you dip the parts into a salt bath at 800-1100* F. Carbon and nitrogen are absorbed at a molecular level hardening the steel in the process. The black color is actually from post process oxidation and is a side effect that has no bearing on the hardness or durability of the part. It is heavily used in the motorsports industry and is surprisingly cheap. IIRC 6 pistons cost around $300 to process about 2 years ago.

JGifford
12 July 2015, 04:09
The Fathom enhanced BCG is getting great reviews. I'm not sure if they are made by the same company, but the BCG in the new Hodge AU-MOD 2 and the one in Erathr3's rifle look like rebranded Fathom enhanced BCG's.

Re-branded Fathom BCG's? Fathom does not make a BCG.

QPQ has several advantages.


#1, it is easy to clean
#2, THEORETICALLY it offers improved durability. Why?
a) A QPQ cam-pin wears much less. This creates less "slop" and subsequently shock-loading during operation.
b) QPQ treated steel on non-QPQ treated steel, sans any lubricant, has a lower coefficient of friction than does steel on steel, both un-treated. This means that the axial loading on the rear of the locking lugs is THEORETICALLY lessened. Which THEORETICALLY will lend to longer bolt-lug life.


The BCG's that FATHOM Arms sells are some of, if not the nicest/best machined BCG's out there, barring a hand-polished JP.

GOST
12 July 2015, 06:02
I knew some people would weigh in with better knowledge than I about the nitride treatment.[:)]

Fathom_Arms
12 July 2015, 11:06
I know they nitride barrels. I assume it's the same treatment? If so I wouldn't really classify that as a "coating" per se. I don't know but there could be virtue in that. I don't know what the end result is by doing that to a BCG.

If the surface of the metal is physically harder though that's a difference that I need to think over.

The black nitride treatment is actually a two "layer" treatment process. The black you see on the outside is a Iron Oxide coating. That coating provides some lubricity, hardness, and sex appeal. When that wears, the nitrogen diffusion layer is exposed underneath. This layer is actually the important part. It changes the metals molecular structure and penetrates the metal around .0005" deep. It provides increased hardness (70 rockwell, off the top of my head), lower friction coefficient, and lubricity (mainly due to the extremely low friction coefficient).

You would be correct. Its a treatment. The Iron Oxide layer could be considered a coating but it is considerable thinner than phosphate or plating (NiB). One of the biggest advantages about nitride is that you do not need to worry about tolerance stacking. You can machine true to spec and not worry about any dimensional changes once the treatment is performed.

alamo5000
12 July 2015, 11:35
The black nitride treatment is actually a two "layer" treatment process. The black you see on the outside is a Iron Oxide coating. That coating provides some lubricity, hardness, and sex appeal. When that wears, the nitrogen diffusion layer is exposed underneath. This layer is actually the important part. It changes the metals molecular structure and penetrates the metal around .0005" deep. It provides increased hardness (70 rockwell, off the top of my head), lower friction coefficient, and lubricity (mainly due to the extremely low friction coefficient).

You would be correct. Its a treatment. The Iron Oxide layer could be considered a coating but it is considerable thinner than phosphate or plating (NiB). One of the biggest advantages about nitride is that you do not need to worry about tolerance stacking. You can machine true to spec and not worry about any dimensional changes once the treatment is performed.

Fort Worth? You're right up the road from me :) (about 2 hours) LOL

I have studied a bit about how they treat barrels so I have a pretty good idea what you are saying. Now that said how is phosphate done? (I don't have any idea) Do you know how hard phosphate is?

Also what is the underlying rockwell hardness of the metal being used in a standard BCG? I am able to relate somewhat to rockwell numbers because thats what they use to test (good) knives...

I am trying to think it through so that I can understand.

SINNER
12 July 2015, 14:09
Phosphate is a coating usually applied by dipping. Phosphoric acid and salt is the agent used. It's actually a form of pickling. Hard to compare Rockwell from one type of treatment to another. Too high of a RW# can indicate embrittlement with phosphates.

alamo5000
12 July 2015, 14:23
Phosphate is a coating usually applied by dipping. Phosphoric acid and salt is the agent used. It's actually a form of pickling. Hard to compare Rockwell from one type of treatment to another. Too high of a RW# can indicate embrittlement with phosphates.

Do you know what the hardness is of the basic metal used in BCGs?

DutyUse
12 July 2015, 15:37
I use to be a dyed in the wool Phosphate BCG user until I tried the Fathom. Now almost every rifle I own runs one. Excellent products, can't recommend them highly enough.

http://images.tapatalk-cdn.com/15/07/12/ddaf11a560b92ffd6e924ed68ad9836b.jpg

UWone77
12 July 2015, 15:51
I use to be a dyed in the wool Phosphate BCG user until I tried the Fathom. Now almost every rifle I own runs one. Excellent products, can't recommend them highly enough.

http://images.tapatalk-cdn.com/15/07/12/ddaf11a560b92ffd6e924ed68ad9836b.jpg

Now that's a collection of Fathom BCG's!

GOST
12 July 2015, 16:58
http://images.tapatalk-cdn.com/15/07/12/ddaf11a560b92ffd6e924ed68ad9836b.jpg

What, no subdued logo Fathom BCG?[BD]

alamo5000
12 July 2015, 17:03
I use to be a dyed in the wool Phosphate BCG user until I tried the Fathom. Now almost every rifle I own runs one. Excellent products, can't recommend them highly enough.

http://images.tapatalk-cdn.com/15/07/12/ddaf11a560b92ffd6e924ed68ad9836b.jpg

That looks awesome! As ya'll know I am still relatively new to the AR game so I only have one rifle (as of right now) but based on a few things: 1) wevo has yet to recommend anything 'crap' to me yet. When you have 5, 6, or 7 people on wevo saying 'get this'... odds are it's gonna be awesome. 2) the nitride thing sounds pretty interesting. 3) it looks pretty bad ass.

In the short term I want to have a 'uh oh' kit just in case something goes out I won't be left up a creek until I can fix it. A spare BCG is high on that list because at least based on my logic moving parts, especially ones that are getting hot and getting slammed around might be the first to wear out or break, specifically I mean gas rings and kotter pins and so forth. I might be totally wrong but that's my thinking.

alamo5000
12 July 2015, 17:14
What, no subdued logo Fathom BCG?[BD]

I think we need Fathom Arms T-Shirts. A big ace of spades logo right in the center like a big superman logo... that would be awesome.

alamo5000
12 July 2015, 17:31
Speaking of an 'uh oh' kit, what do all ya'll think I should get? Where should I get them from? I have no idea where to get spare gas rings, kotter pins, or whatever else I might need.

Based on your (collective) knowledge what parts are most prone to wearing out?

I am still probably going to get a spare BCG... I don't want to be out in the field shooting and have a gas ring go out and then just blow the whole day, but I still want to get a little kit of stuff that is prone to wear out or break.

GOST
12 July 2015, 17:33
I would get spare bolt instead of a whole BCG.

UWone77
12 July 2015, 17:35
Speaking of an 'uh oh' kit, what do all ya'll think I should get? Where should I get them from? I have no idea where to get spare gas rings, kotter pins, or whatever else I might need.

Based on your (collective) knowledge what parts are most prone to wearing out?

I am still probably going to get a spare BCG... I don't want to be out in the field shooting and have a gas ring go out and then just blow the whole day, but I still want to get a little kit of stuff that is prone to wear out or break.

Spare Bolts <---plural. Shoot enough, you will break bolts. Gas rings, and cotter pins (since I lose one from time to time)

DutyUse
12 July 2015, 17:38
I think we need Fathom Arms T-Shirts. A big ace of spades logo right in the center like a big superman logo... that would be awesome.

For a logo I really dig the Fathom Spade. It's neck and neck with the Ol iron cross from Noveske. In fact the Fathom Spade is the only "tactical" sticker on my truck. Kinda sad they went with the new logo.. It's still looks good but that Spade peaking out the ejection port looks killer IMHO


What, no subdued logo Fathom BCG?[BD]

I really wanted one, but you couldn't order then directly from Fathom. Not sure if Blacksheep are still offering them now

alamo5000
12 July 2015, 17:47
Spare Bolts <---plural. Shoot enough, you will break bolts. Gas rings, and cotter pins (since I lose one from time to time)

Rainier Arms doesn't have them on their website. Ideally I would like to get a a couple cotter pins, a couple of sets of spare gas rings, and a couple of spare bolts. Ideally it will be the bolt that matches my carrier (hence why I would prefer to get it from Rainier) but I don't know if that matters or not.

Where can I round up those spare parts (something good and reliable) considering that I might not be able to get them from RA?

DutyUse
12 July 2015, 17:54
Rainier Arms doesn't have them on their website. Ideally I would like to get a a couple cotter pins, a couple of sets of spare gas rings, and a couple of spare bolts. Ideally it will be the bolt that matches my carrier (hence why I would prefer to get it from Rainier) but I don't know if that matters or not.

Where can I round up those spare parts (something good and reliable) considering that I might not be able to get them from RA?

BCM I wanna say sells a BCG spare parts kit. But honestly it doesn't matter if the bolt and carrier are the same material. I believe AIM sells a BCG with a nitride bolt and a NiB carrier (or vice versa).

If it was me in your situation, and I knew another AR were in my future id just buy a whole BCG to use as a spare and then to have for a second rifle when you got more money later

toolboxluis00200
12 July 2015, 18:02
I use to be a dyed in the wool Phosphate BCG user until I tried the Fathom. Now almost every rifle I own runs one. Excellent products, can't recommend them highly enough.

http://images.tapatalk-cdn.com/15/07/12/ddaf11a560b92ffd6e924ed68ad9836b.jpg

I need to save so money

GOST
12 July 2015, 18:02
Rainier Arms doesn't have them on their website. Ideally I would like to get a a couple cotter pins, a couple of sets of spare gas rings, and a couple of spare bolts. Ideally it will be the bolt that matches my carrier (hence why I would prefer to get it from Rainier) but I don't know if that matters or not.

Where can I round up those spare parts (something good and reliable) considering that I might not be able to get them from RA?

I've always had great luck with Aim Surplus. Great prices and fast.

http://www.aimsurplus.com/catalog.aspx?groupid=723&name=Bolts+%26+Bolt+Carrier+Groups

alamo5000
12 July 2015, 18:05
BCM I wanna say sells a BCG spare parts kit. But honestly it doesn't matter if the bolt and carrier are the same material. I believe AIM sells a BCG with a nitride bolt and a NiB carrier (or vice versa).

If it was me in your situation, and I knew another AR were in my future id just buy a whole BCG to use as a spare and then to have for a second rifle when you got more money later

That's what I was going to do, but I don't know when that next rifle will appear [:D] One day when I get the urge parts will magically start showing up.

In the mean time I most definitely want/need spare parts. I kind of like the idea that Uwone mentioned... if I can get the bolt only for a reasonable price then why not? I still want gas rings and cotter pins too. If I blow a gas ring I am going to need to fix it. If I can just put a spare bolt and whatnot and a minimal amount of tools in my bag then that's even better.

alamo5000
12 July 2015, 18:08
I've always had great luck with Aim Surplus. Great prices and fast.

http://www.aimsurplus.com/catalog.aspx?groupid=723&name=Bolts+%26+Bolt+Carrier+Groups

I am going to check them out and compare. They are on the list. Thanks!

What about just plain old gas rings and cotter pins?

GOST
12 July 2015, 18:15
I am going to check them out and compare. They are on the list. Thanks!

What about just plain old gas rings and cotter pins?

I've used Joe Bob and they have been very good also.

http://www.joeboboutfitters.com/Bolt_parts_BCG_s_s/889.htm

alamo5000
12 July 2015, 18:19
I've used Joe Bob and they have been very good also.

http://www.joeboboutfitters.com/Bolt_parts_BCG_s_s/889.htm

I can buy a whole new BCG for what some of these places are asking for just the bolt...

GOST
12 July 2015, 18:35
JP products are nice but very expensive. Aim Surplus probably has the best prices on bolts.

alamo5000
12 July 2015, 18:43
JP products are nice but very expensive. Aim Surplus probably has the best prices on bolts.

I am cooking dinner now so I will look around and see. Hopefully I can get gas rings and cotter pins all in one spot so I don't have to pay some stupid shipping charge for a $1.50 part.

SINNER
12 July 2015, 19:08
I agree with the spare bolt advice to start. Even more so when you get into some of the oddball calibers with larger bolt face pockets. 7.62x39 bolts break about twice as often,

Some links for good quality components.

http://www.bravocompanyusa.com/BCM-Gas-Rings-p/gas%20rings%20set%20of%203.htm

http://www.bravocompanyusa.com/Retaining-Pin-for-Firing-Pin-AR15-p/retaining%20pin%20ar15.htm

http://www.bravocompanyusa.com/BCM-SOPMOD-Bolt-Upgrade-Rebuild-Kit-p/bcm%20bolt%20upgrade%20kit.htm

alamo5000
12 July 2015, 19:32
http://www.bravocompanyusa.com/BCM-AR15-Bolt-Assembly-MPI-p/bcm-bolt-assembly-mp.htm

Good? No good? Is the price pretty decent?

GOST
12 July 2015, 19:36
http://www.bravocompanyusa.com/BCM-AR15-Bolt-Assembly-MPI-p/bcm-bolt-assembly-mp.htm

Good? No good? Is the price pretty decent?
Definitely GTG.

alamo5000
12 July 2015, 19:47
What about a firing pin? Would it be a good idea to have a spare? Or is it one of those things that just don't really break all that often?

GOST
12 July 2015, 19:57
I've never broke one but it wouldn't hurt to have an extra.

Slippers
12 July 2015, 20:01
I've yet to see one break in person, but I have seen poorly reloaded ammo cause a string of pierced primers, which eroded the tip of the pin. This makes it more likely to continue to pierce primers.

Extra parts like the firing pin are so cheap that I'd recommend most people that shoot regularly to keep spares around. My spare parts box has:

1. firing pin
2. extractor
2. extractor pin
3. extractor insert
4. extractor spring
5. a few gas rings
6. ejector (typically goes flying into outer space the first time you remove the ejector roll pin)
7. ejector spring (same as safety detent spring)
8. ejector roll pin
9. magazine release spring (had a friend visiting from california lose one at the range when he was swapping out his bullet button)

I also keep a complete BCM bolt carrier group on hand, but that's kind of expensive. Still, it's worth it's weight in gold when you are diagnosing a problem rifle at the range.

DutyUse
12 July 2015, 20:02
http://www.bravocompanyusa.com/BCM-AR15-Bolt-Assembly-MPI-p/bcm-bolt-assembly-mp.htm

Good? No good? Is the price pretty decent?

Excellent. BCM is what all others are measured against in my book. However at 80+ shipping you could almost get a complete Fathom. Just saying [BD]

GOST
12 July 2015, 20:03
Good advice Will.