I have several and have and wanted to find out what they are going for?
Are these the unfinished ones that are around?
Where did they come from?
I think those "12-88"' ones don't have the IMI "proof" acceptance stamp, meaning they weren't "proof" tested by IMI, so were not "accepted" to put on production rifles.
I think those "12-88"' ones don't have the IMI "proof" acceptance stamp, meaning they weren't "proof" tested by IMI, so were not "accepted" to put on production rifles.
This is correct. No circle-E or Circle-P proof means they were rejected for some reason, despite the reason not being clear.
Were all of the barrels in question marked 12-88?