30 Rd Hardback and Splitback SEY Magazines

[thorin6]

Having read up on what distinguishes a USGI 30 round magazine from the aftermarket and reproductions out there, I've been trying to acquire a few early USGI 30 round mags. After some searching I picked up two splitlback SEYs and a splitback J marked mag. I read about the hardback magazines, but only saw pictures of one on GB where the seller was asking $125 for a NIW version.
Then I read a GB ad for a 30 round magazine in a vintage box. The written description left much to be desired, but the pictures seemed to show a hardback SEY magazine, and it fit the description in the PDF file I downloaded from the CMP website. It had a "Buy It Now" price of $27, so I picked it up. Here is a picture of the hardback SEY (on the right) next to a splitback SEY (on the left). It looks correct to me, and as far as I know, no one has made an aftermarket or reproduction hardback magazine. Any comments are welcome.

Information

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[Bubba-7]

I have two SEY hardback and they look just like your pictures.

[A. F Medic]

Do all the mags have the makers marks on them? I have a 30 rounder and it is only marked M2 It is a split back...

[thorin6]

Some 30 round mags are unmarked; most of those are aftermarket/reproduction/fakes, although there are some that are thought to be made by the same manufacturer that made the J marked magazines that are USGI and made during the Viet Nam War. The M2 marked magazines (I have several of those) are considered aftermarket, not USGI. CMP has a PDF file that you can download (I don't have the link, but it's accessable through various search engines), but it takes some time to read the file and understand what you should look for because there are no pictures. There are so many aftermarket 30 round magazines, marked and unmarked, it's hard to sort them out. If I remember correctly, all USGI magazines were originally blued, and I believe that all USGI magazines are marked with the manufacturer. AYP is a Belgium manufacturer that made 30 round magazines to USGI specs and are considered of equal quality. There are fake SEYs out there, but the font is different and they vary in construction, which is why you need to take time in understanding what is correct.

[G26ster]

I believe this is the CMP link to 30 rd magazine info

http://www.thecmp.org/pdfs/Carbine_3...ember_2007.pdf

[Mikey51]

Here's a KI. I have a few, but this, I think, is the only genuine one. Mike.Attachment 19597Attachment 19596Attachment 19595Attachment 19594Attachment 19599Attachment 19598

[JimF4M1s (Deceased)]

Here's some I have. Can't find the others right now.

[Rustship]

I'll take 2 at $27.00 each....LOL

[datanull]

Here's some I have. Can't find the others right now.

Fascinating; is there any significance to the difference in the 4 magazines that do not hold then bold open when empty versus the ones that do.

[thorin6]

My understanding is that original USGI magazines had the follower that would hold the bolt open after the last round was spent. However, given the ease that one can replace the follower, that in itself wouldn't be a reason to consider any of JimF4M1s' magazines wrong. Crimps, base plates, bolsters (the pieces that hold the base plate), and other evidence makes all of them look right. I don't think anyone has found a manufacturer that has reproduced the hardback 30 round magazines; only the splitback ones have been reproduced and/or faked to the best of my knowledge.