Ive owned 5 GI carbines and currently have 3. All of them were upgraded at some point. All of them were in pretty good shape when I got them, but all also required some work to get them to be "shooters".
All had the rear sights replaced and a bayo mount up front. Three of them did not have the front sight rezeroed to the rear sights when that was done and I had to do that.
All of the rear sights were knocked out of their staking, and all were in various states of looseness. I restaked them, and that made things a lot better. When they are properly staked, they do not appear to be centered on the gun. Ive always wondered if people knocked them over thinking they were off and that's why they were loose. Mine all seemed to zero right up when in the original staking.
I have three with round bolts, and two that still have a flat bolt. All of them needed to be rebuilt. New extractor and ejector and springs. All got a new recoil spring too while I was at it.
Two of my guns had the upgraded mag release, all of them have the upgraded safety.
GI mags were a major issue, and a big problem for reliability. I got a number of them with the guns when I got them, and only a couple made it to the range mag bag. 99% of the time there is a stoppage, its one of those mags that's in the gun when it happens.
The Korean mags that are available now are the way to go. Reasonably priced, some come with a hold open follower, and all seem to be 99.9% for function. That goes for the 15 and 30 rounders.
Once I got everything squared away, reliability went way up, and they all seem to shoot well, and all about or better than 3-4 moa. The only thing that still drives me nuts with them is, they will throw brass in a random and sporadic 360* arc. One might fall to your right, right at your feet, the next is at 8 o'clock, 15 feet away, then the next one 10 feet right in front of you. Drives me nuts. I reload for them, and 30 Carbine brass isn't the cheapest.
If you do pick one up, take a look at the CMP's website. That have a lot of good info over there on them, and were a big help at trying to get things tweaked for me.
Theres a lot of good info around the web as well if you get to looking around, and can help you figure out just what you might have.
Im a shooter and not a collector. "Shooting accumulator" is probably a better description.
Im always looking for a decent "original" for a shooter, and Im not too worried about what I have as far as a collector goes. Like the M1's, "most" are not 100% matching as far as "maker" parts go. There seem to be a lot of people who think that if all the parts match, maker wise, they have a "correct" gun. I think the truth is just the opposite, but, whatever.
I will tell you if you have any M1, and probably Carbine parts as well laying around, you might be sitting on a gold mine. I sold off a bunch of M1 parts 4 or 5 years ago on eBay that I had accumulated over the years that were sitting in a box and made a killing. Things I paid $5, $10, $20 for at gun shows over the years were going for $100 or more. I sold one front handguard that I paid $10 for (still had the sticker from the show on it), for $200! Some people are straight up nuts!
But that's OK too.
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