Black or blue?

I can never remember

That would be black.

Thanks. I just got a Stag that has a blue one. Is there any major difference?

On a carbine, I would say big time.  Rifle?  Meh...  I never had an issue on a 20", but I upgraded anyway.

You should replace the extractor spring with the correct 5 coil spring at the same time.  You probably hace a 4 coil spring, and it will not last long under heavy use in a carbine.

Here is your easy fix.  The first time you do it the spring will be hard to compress and you'll doubt yourself.  Just muscle through it and you'll be in great shape.

Bravo Company Extractor Spring Upgrade Kit

Have you had any issues so far? That would be my 1st concern.

5-coil with black insert is spec for any length barrel. If you do not have that configuration, I suggest it strongly.

I use the BCM black inserts on my carbine, midlength and rifle gas systems.

I also use the whole BCM extractor upgrade kit on my carbine gas system.

My midlength and rifle are fine as is and I only upgrade them with just the Crane O-ring.

its suppose to be black..but i've seen both a lot nowadays

Quoted: Have you had any issues so far? That would be my 1st concern.

No issues. It hasn't been fired. I run the BCM kits in both of my other rifles without issues.

Quoted: 5-coil with black insert is spec for any length barrel.

Negative.  Spec is the GOLD spring from Colt.

Quoted: Quoted: 5-coil with black insert is spec for any length barrel. Negative.  Spec is the GOLD spring from Colt. i153.photobucket.com/albums/s204/TheMocoMan/AR-15%20Technical/Gold_Spring.jpg i153.photobucket.com/albums/s204/TheMocoMan/AR-15%20Technical/ColtExtractor.jpg i153.photobucket.com/albums/s204/TheMocoMan/AR-15%20Technical/Std-VS-Gold3.jpg

I stand corrected. Perhapse Sabre was referring only to their line-up when they told me that. Is the gold spring "stiffer" than the 5-coil when installed?

Quoted: Quoted: Quoted: 5-coil with black insert is spec for any length barrel. Negative.  Spec is the GOLD spring from Colt. i153.photobucket.com/albums/s204/TheMocoMan/AR-15%20Technical/Gold_Spring.jpg i153.photobucket.com/albums/s204/TheMocoMan/AR-15%20Technical/ColtExtractor.jpg i153.photobucket.com/albums/s204/TheMocoMan/AR-15%20Technical/Std-VS-Gold3.jpg I stand corrected. Perhapse Sabre was referring only to their line-up when they told me that. Is the gold spring "stiffer" than the 5-coil when installed?

I'm with you, 12 gauge.  I've never seen that before.  And I thought the BCM kit was the bomb...

I cheap approach before the new springs was the O-rings (worth pennies)

I'm getting slow, TheMocoMan beat me to it..............

http://i153.photobucket.com/albums/s204/TheMocoMan/AR-15%20Technical/Gold_Spring.jpg

There was an article about extractor springs in Guns magazine or whatever one it was.  Anyway they stated the blue ones, the dfender, o rings, etc.  They did however state that Chrome Silicon seemed to be the best and last forever.  They also stated that if you use a Chrome Silicon spring, don't use an o-ring or defender in conjunction with a CS as it applies over 400% more spring tension which is way too much.

Yes, I recall reading that as well.

Quoted: Is the gold spring "stiffer" than the 5-coil when installed?

Good question and I honestly don't know.  The gold spring is MUCH stiffer than the spring I replace it with.  But how it compared to the 5-coil I couldn't say.

It's not that big of an issue.  Some just like the added insurance.  I'm not a fan of the o-ring as I feel it's an out-of-spec modification and can add that 400% more tension like the post above me stated.  I mean Jesus Christ people the extractor is SUPPOSED to have some movement otherwise the fu** thing wouldn't work at all.

I'd leave well enough alone until you see problems.  Recreational shooting with the blue insert and spring will probably last years.

Black or blue insert??... the answer is it does not matter as both are identical in every way other than color.  I am supprised noone mentioned this fact this far in.

The blue buffer is obsolete, the black buffer is stiffer.  That is for USGI, Colt/FN, etc.  Who knows with look-a-like parts.

There is only so much room for the spring. Why does everyone think that a five coil spring has to be stronger than  a three or two coil one?

home.earthlink.net/~bazillion/design.html#prin




Just noticed the spell check is back.

Quoted: There is only so much room for the spring. Why does everyone think that a five coil spring has to be stronger that  a three of two coil one? home.earthlink.net/~bazillion/design.html#prin

Good link.  It's the new math.

Quoted: Thanks. I just got a Stag that has a blue one. Is there any major difference?

Ive shot TONS of ammo with the Blue insert

My cmt had the blue also as did my Bushmasters

Quoted: Black or blue insert??... the answer is it does not matter as both are identical in every way other than color.  I am supprised noone mentioned this fact this far in.

True

But I updated my CMT bolt anyway

Quoted: The blue buffer is obsolete, the black buffer is stiffer.  That is for USGI, Colt/FN, etc.  Who knows with look-a-like parts.

There is no functional differenece.  The color is only used a vsual marker for the installed spring type.  There is ZERO benefit to using a black insert over a blue insert... not even a little bit.

Quoted: Quoted: The blue buffer is obsolete, the black buffer is stiffer.  That is for USGI, Colt/FN, etc.  Who knows with look-a-like parts. There is no functional differenece.  The color is only used a vsual marker for the installed spring type.  There is ZERO benefit to using a black insert over a blue insert... not even a little bit.

We disagree.  

Perhaps you are correct in regards to look alike parts.  In USGI buffers the blue one is demonstratively squishier then the black one.  I would not be surprised if commercial look alike buffers are available in different colors with many of them the same other then color.

In USGI weapons the color of the buffer has never been a visual marker for the spring.  The buffer and spring can be separated so the color of the buffer serves no purposes in ID'ing the spring.

I will post up details with hand puppets, visual aids, here in a bit.

Quoted: I cheap approach before the new springs was the O-rings (worth pennies)

That is my approach.

One Quib directed me how to get the extractor off the bolt,  I installed an o-ring that I have by the dozen already.

A much simpler, quicker and cheaper way to make sure that the extractor was the cause of the double feeds on my 11 1/2" barrel.   If it solves the problem then I may do the other upgrade when the o-ring is worn out.

I surprised to hear the o-ring would be a deficient solution, since BCM threw in one for free with my purchase of one of their bolts.  No one has said a bad word about them.

Anyhow, do you just put the o-ring down and re-install the extractor...compressing it all down?  The o-ring didn't seem to fit over the spring (with blue insert).

This is a extractor guide for OEM, USGI, Colt, FN, etc, has nothing to do with cheapo look alike parts.

The extractor buffer is a buffer for the extractor spring.  It is not a color coded spring identifier, that is why it is called a buffer rather then a color coded spring identifier.  The original idea was to extend extractor spring life. For example, in December of 1965 a lot of 4,800 rifles was almost rejected because one had a extractor spring break during a endurance test (508 RFW-122).



From left to right:

original spring 1959-1971
white buffer 1972-??
red buffer ??-1982
blue A2 buffer 1982-1993 or so
black buffer 1994-current (still in use on M16A3 and A4)
black buffer with M4 gold spring 2003-current
SOPMOD O-ring

Extractor springs are the same for USGI rifles/Carbines other then the original spring, and the new M4 gold spring.  

The black buffer is demonstratively stiffer then a black one.  Here is a blue A2 buffer compared to a black one:


Pic by CJan_NH.

Here are some measurements I took with my trigger pull gauge.  This is what the gauge read for the weight needed to get the extractor fully extended:

long spring, no buffer:

4.0 lbs

White buffer:

3.0 lbs

Red buffer:

3.5 lbs

Blue buffer:

2.25 lbs
2.5 lbs

Black buffer used on M4's, and the M16A4:

3.5 lbs (well worn M4A1)
4.0 lbs (brand new M16A4)
2.25 lbs (well worn M4A1)

Black buffer, with gold spring as used on late M4's:

could not get a good reading, kinda stiff ya know, well over 5.0 lbs

Black buffer, with standard spring, and SOPMOD O-Ring:

could not get a good reading, well over 7 lbs on a well worn M4A1

These are not real scientific, too small a sample.  There is some debate in regards to when the blue buffer was introduced.

In regards to the SOPMOD bolt upgrade kit, this was a Band-Aid for the old M4A1 extractor set up, that is the black buffer and silver spring. Due to the location of the gas port on the M4/A1 some of them had extraction problems (had one myself). Colt's had developed the specific gold spring and black buffer for the M4/A1 to address this, but the Big Army did not want to add another part to the system (gold spring). So SOPMOD came out with the doughnut to fix it. Since then Big Army has approved Colt's gold spring set up, and M4/A1's are now delivered with them, and I would not think the SOPMOD kit is needed on these.