[ARCHIVED THREAD] - Help Identifying Bolt Markings

Posted: 4/17/2011 12:26:55 PM EDT

Can anybody ID these two bolts? I have an idea but I don't recognize the underscoring of the M on one and the underscoring of the F on the other. The labels had peeled off of the ealed bag, they had never been openned. Both have black rubber inserts on the extractor spring.TIA

Posted: 4/17/2011 12:28:55 PM EDT

[#1]

FN bolts are typically marked MPF

Here's a picture I took awhile back:

Also, you can check out the extractors to see if they are "F" marked:

Posted: 4/17/2011 12:29:57 PM EDT

[#2]

Pretty sure they say MPI.....with random marks.

edit: wrong again.

Posted: 4/17/2011 12:37:00 PM EDT

[#3]

One last note... FN bolts have semi-elliptical cuts under (rear of) the lugs. See the picture below.

I don't think these serve a purpose, as they are from the tooling that FN uses to chamfer the lugs.

Colt typically has a "slash" mark under the lugs.

Posted: 4/17/2011 12:37:30 PM EDT

[#4]

FN.

Posted: 4/17/2011 2:23:06 PM EDT

[#5]

I checked and each extractor is marked "F" like the photo, I wonder if there is any significance to the underscoring of the M in MPF and the F in MPF on each bolt. I picked these up as spares and price was right.

Posted: 4/17/2011 3:41:20 PM EDT

[#6]

Mine says MPC on it I am sorry for the bad cell phone picks but mine is a COLT . I bought mine from a military bend for 40.00 bucks it has a blue insert .It is shiny at the face of the bolt head and I was wondering if I need to head space it or would it be just fine

Posted: 4/17/2011 8:32:54 PM EDT

[#7]

Is the extractor spring copper colored or grey?

[ARCHIVED THREAD] - Help Identifying Bolt Markings

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[ARCHIVED THREAD] - Help Identifying Bolt Markings

[ARCHIVED THREAD] - Help Identifying Bolt Markings