Can someone please confirm the correct size of the ejector roll pin? I see two conflicting sizes.

The diameter seems to be consistent at 1/16 inch (.062) but I see different posts for length. The two length sizes I see are either .375 ( which I think is 3/8") or .437 (which I think is 7/16").
So anyone know which one it is?
Thanks.

http://www.biggerhammer.net/ar15/pins.html

http://www.degrata.com/pdf/AR15_Pins_and_Springs.pdf

Uh ... yeah, thanks for that. But that is what I was talking about. I saw both of those, but those say that it should be .437 which is 7/16" (I think) but no one sells that size. Brownells and places like that seem to have the 3/8" so that is kinda leading me to believe that those links might not be correct or must be purchased someplace that I am unaware of.
If you do a search here you see a few different topics with 2 different sizes. So while I appreciate the links, and quite often those links are helpful, this time they are not.

What I was hoping for is someone who actually knows the correct size. Either they have measured them or have one available to measure.
Thanks though.

Just look in the TM manual and google the part number. http://milspecfastenerscorporation.thomasnet-navigator.com/item/roll-spring-pins/spring-pin/ms-16562-98


But you can buy the 7/16" pins. I like them better and use them.
http://www.mscdirect.com/browse/tn/Fasteners/Spring-Pins?searchterm=spring+pin&navid=4287884576#navid=4287884576+4287770951+4287833958&searchterm=spring+pin

http://www.mcmaster.com/#spring-pins/=14n22xi

OK, after much research I have found out the correct answer. I took the pin out of a factory stock default Colt and measured it. It was 3/8 long. But after doing a lot of reading and examination of the bolts I have I found that the correct pin size is 7/16; but 3/8 is used sometimes. The opening is small enough that there is no shearing force which could cause it to bend because it is too small.
The only down side I see to using the 3/8 is that it is a little bit harder to center it.

So bottom line the correct spec pin size is 7/16 long but it is harder to find. Thus 3/8 can be used and is used by some manufacturers.

Thanks to j3_  you can find the correct 7/16 pins if desired.

The correct size is 3/8". I linked it in my post. That is from the actual part number from the governments technical manual.

The websites like BiggerHammer list it as 7/16. I don't know where they get that from but I see no websites that list it as 3/8. I'm not disagreeing with you because it seems as though companies use 3/8 but i just don't see it listed anywhere.
I don't have access to a technical manual though. Can you please provide me with a link to it? I would love to have a look at an official technical manual for the M16/AR15; not just for this pin but for numerous things. That would be a great thing to have. I appreciate your help in trying to figure this out.

The link to manuals is on the AR15.com homepage here is the TM. The part numbers are in the back pages. http://www.ar15.com/content/webPDF/TM9-1005-319-23.pdf

It's confusing because there are 2 different lengths that are very commonly used and sold for ejector roll pins.  

On some brands of bolts, like LMT, you can only use one size roll pin (the shorter ones).  

Also, on some brands of bolts, the roll pins can only go into and out of one side of the bolt.

HighSpeedSteel

The correct answer was posted three times.

If you don't want the answer, why ask the question?

The question was not answered 3 times. Links were given and, if you bothered to look at those links, the answers given contradicted the other answers given. So if 3 people answer and you get 2 different answers that are opposite each other then is the answer given? Now I notice that you posted but did not answer. I am always fascinated by people who post to a topic but offer nothing. I am curious ... if you have nothing to offer why post? I have not been rude ot anyone here so I don't know why you find the need to do so. I am after facts; not opinions.

j3_,
Thank you for that. I will check that out. Very much appreciated. I was not aware that they were available here.

High Speed Steel,
Agreed. It seems that the standard size is both of them. Depending on who you ask or what company you check. So the answer is ... it depends. But I will check out the manual and see if there is a "milspec" standard, which of course does not necessarily mean that some companies use the other size. But at least it is narrowed down to one of the two.

Wow, OK this is even weirder. After reading the manual it does not say what the pin size is. It does say a part number. But, of course we have no way of knowing from that document at least, what the governments pin size for that given part number is.
However, even if we assume that the part number that websites use on the internet is indeed the same part number that the military uses for that pin then we have a problem because you copied the wrong part number. The part number you typed ended in an "8" but it is not an "8" but a "B". If you search for that part number ending in a "B" then the part size comes up as 11/16. Yet a third size totally.
From the manual ... [4 PAOZZ 5315005975086 96906 MS16562-9B]

http://military-fasteners.elitefastenersinc.com/item/ms-pins/ms-16562-spring-pins/ms-16562-9
and
http://milspecfastenerscorporation.thomasnet-navigator.com/item/roll-spring-pins/spring-pin/ms-16562-9

But I think a 11/16 pin might actually fit from edge to edge so that might actually be the "correct milspec" size, as weird as that might be because zero civilian rifles that I have seen use that size. It would be cool to see a real military issue bolt and see what size it has.
I'm going to pull my bolt again measure the size of the channel/hole length and see what it is. Of course this is becoming more for fun now then anything else because it seems that civilian rifle companies tend to do what they want.

The actual hard copy manual says 8 not B. I am looking at one . There's no mystery here. No need for Shaggy or Scooby Do.
If you go further in the manual to page I-3 you will see the part listed with the 8 not B.


You can look stuff up with the nsn number also
https://www.iso-group.com/NSN/5315-00-597-5086 all you get is the specs for a 1/16" - 3/8" long spring pin

Would've gotten away with it too if it weren't for you kids!

Don't know who BiggerHammer is but someone should tell him that his website is wrong and lots of people use that for reference as witnessed by the first few posts of this topic. And the typo in the manual.

Thanks for helping solve that mystery j3_. Much appreciated.