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Yes there are different springs, amount of coils, measurement differences, and material differences. Best I can tell right or wrong there is a stock number for the old rifle spring, two different ones for newer rifles with three shot burst triggers, and one newest one for the newest carbine. Coils seem to vary from 7 to 71/2 depending on the spring. Material varies between two types stainless and music wire. Wire diameter measures without considering tolerances between .020" to .024". Lengths varies between .350" to .366".
I got most of that by measuring known Colt springs I bought. You get lots of different counts and heights on commercial springs I have checked and the wire diameter on most of them was the .020".
Numbers I found were:
61925  (13629)
8448594
9349116
12972695

The new stiffer .024" music wire spring are showing up know.

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The newer stiff .024" disconnector springs I just put in bag and don't use. I am sure they have a purpose but I have never had a problem with the older green stainless ones and they seem easier to install because of the small wire diameter.

The extractor spring wire diameter changed and they made the insert stiffer or a higher durometer rating. I think they colored them gold for identification. Brownell sells them under there Colt schematic and they are available from other vendors also. The o-ring is just something places or manufactures are adding on. I have a pile of them where I take them off. Never cared for how hard they make it for the extractor to function or the case to be pushed off by the ejector.
Extractor spring
https://www.brownells.com/schematics/colt-/ar-15-bolt-carrier-assembly-sid802.aspx#s10818sid802
Two of the disconnector springs Bottom green one is the 7 coil .020" number and the black one above looks to be the 7 coil .024" spring.
https://www.brownells.com/schematics/colt-/m16-m4-lower-receiver-fire-control-full-auto-sid853.aspx#r3sid853

The lengths on springs sometime have tolerances, sometimes just say reference, and sometimes say other things like after they are fully compressed. They generally give a compressed value range it has to meet. The wire diameter, coil count, and outside dimensions on most springs I have measured were in tolerances but lengths varied around a referenced number.

To give an example the green disconnector spring is .350". If you measure a new one it may be .370". If you fully compress it coils touching it should be shorter when you let off closer to the .350" number.

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Disconnector springs can be found a lot cheaper a lot of places. I just linked that for general info on the springs.

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Try Damage Industries for both disconnector springs, the older "green" and newer USGI longer, stiffer disconnector-springs discussed earlier in the thread.  

They also have a good USGI-copy of the Factory Colt Defense "gold" extractor-spring for less than a $1.00.  It is a good, stout extractor-spring, much stiffer than the old, soft "M16" spring that everyone else sells with their new BCG's that comes a rubber o-ring.  

Their "five-coil" extractor-springs are fine but they aren't as stiff as their USGI "copper"-colored springs for less than a buck, they're just longer and cost more.  Shipping is $2.00 for anything.

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You just seem to be missing you where already given the part numbers and the green one is not the newest and not the M4 or M4A1 one it is the last number. The M4 is actually a three shot burst that uses two springs a 9349116 on one side and the newer 12972695 listed with the thicker wire on the other side. You can look the newest number up in the newer military TM manual. The drawings most all this are online all you have to do is be able to find and read them.

What do you mean “the last number”? Last number in whose post? The one where “i was told” lists the black one as the last number. Sorry, i cannot figure out the meaning of that sentence. Sincerely.


The new copper plated extractor spring everyone calls gold is not .020" it is .026". Easy enough to measure. You can find all the part numbers and follow them through the years in the back page drawings and info posted in the military Technical Manuals. Even if you can find the drawings online you can order the Colt parts by number and count the coils and measure the wires to get the information. Calling companies will get you nowhere because if they have other companies info to manufacture something they are likely under agreement not to release the information or design.

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The M4 three shot burst has two disconnector springs and two disconnectors in a wide trigger with two pockets for the springs.  One part number goes on one side for the cam disconnector and the other part number goes on the other side for the other disconnector.