I want a Remington R51 but there are things I must first know.

Look at the manufacturer location engraved on the frame.

Gen 1 was made in Charlotte NC at Para Ordnance.

Gen 2 was made in Huntsville AL.

The later magazine where better, the early Gen 2 magazines might need one coil cut off the spring if you have issues with jamming in the first round or two out of the magazine.

The early serial # gen 2s used the remaining gen 1 frames produced in Charlotte NC and the rest of the gen 2s were made in Huntsville AL. So, you can get a gen 2 with either a Charlotte or Huntsville engraving.

The only external difference between the gen 1 and 2 that I know of is the location of the R51 logo on the slide:
The gen 1 had the R51 logo placed low on the slide near the slide serrations. The gen 2 has the R51 logo higher on the slide and right behind the ejection port.
Gen 1


Gen 2

Another external difference: Look for setscrews in the sights.

lysanderxiii said:

Another external difference: Look for setscrews in the sights.

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Yup, when I called remington withe the gen1 vs gen2 question, they told me to look at the rear sight. Gen2's will have a set screw, gen1's will not.

I gotta ask. Why?

My Gen2 has been flawless. The Gen1 received by my FFL around a year before was horrible, you couldn't get it to feed and the slide to barrel fit was so tight you couldn't get it to cycle. He sent it back.

I got mine cheap and then was able to get a new Crimson Trace laser for it at $30 when CDNN blew those out.

I like the pistol, wanted one when they came out but waited as I am always a late adopter of things. Glad I did in this case. Mine has run great. I like the retro design and the mechanics of it are pretty unique which I appreciate.

If you can get a Gen II pistol (guess that is what I have) for a fair price I would.

Kinda apples and different apples, I know, but I have an original, vintage M51 and it has been 100% reliable.

The magazines don’t really like being loaded with 7 rounds. Weird things happen with the second round when loaded 7+1. Load the gun to 6+1 and it works fine. Not ideal, but it’s just the way it is.

Zendude said:

The magazines don’t really like being loaded with 7 rounds. Weird things happen with the second round when loaded 7+1. Load the gun to 6+1 and it works fine. Not ideal, but it’s just the way it is.

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That is likely an early Gen 2 magazine. The springs where too long causing issues if loaded 7+1. The solution was to clip one coil off the spring to reduce the up pressure. They usually run fine 7+1 after that modification. If you compare it to a later Gen 2 magazine you will see the only significant difference is the magazine spring length.

A friend has one, the only malfunction I have seen was from an overly long round.
But he used his FBI badge to get in and give the Huntsville manager a rundown on the little gun's shortcomings.

Only issue I had with my Gen2 was when the magazines were loaded to 7. IIRC I took about 1/8 inch off the legs on the plastic followers, which has made it 100% feeding now with 7 as it should have been. I did not have to alter the magazine springs although I was prepared to if needed. Like you, I knew it was a bit of a risk when I bought it but I wanted one and was prepared to possibly deal with that.

lysanderxiii said:

Another external difference: Look for setscrews in the sights.

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I vaguely remember reports of loose rear sights. Is this what they did to fix that?

mcb said:

That is likely an early Gen 2 magazine. The springs where too long causing issues if loaded 7+1. The solution was to clip one coil off the spring to reduce the up pressure. They usually run fine 7+1 after that modification. If you compare it to a later Gen 2 magazine you will see the only significant difference is the magazine spring length.

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I’ll give that a try!

PCFlorida said:

My Gen2 has been flawless. The Gen1 received by my FFL around a year before was horrible, you couldn't get it to feed and the slide to barrel fit was so tight you couldn't get it to cycle. He sent it back.

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How many rounds do you have through your Gen 2?

I would guess a thousand or so, runs perfectly. It was my EDC until the Sig P365 came out with increased capacity. My wife carries it now.

lee n. field said:

I vaguely remember reports of loose rear sights. Is this what they did to fix that?

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Yes.

Why do you want one when there are so many quality sub compact 9mm?

groundhog34 said:

Why do you want one when there are so many quality sub compact 9mm?

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Really. Interesting re-introduction of the tech, but it fell apart in execution. Unless he's looking for it for the sheer quirkyness of it, the Art Deco (ish) retro styling, or the challenge of getting it to work, there are many, many good options if one is looking for a slim and compact 9.

lee n. field said:

Really. Interesting re-introduction of the tech, but it fell apart in execution. Unless he's looking for it for the sheer quirkyness of it, the Art Deco (ish) retro styling, or the challenge of getting it to work, there are many, many good options if one is looking for a slim and compact 9.

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The design is very intriguing and particularly well suited to a concealed carry pistol. The styling is certainly different, but buying a gun just for appearance would seem shallow.

Gen 1 guns were a total debacle, but they were all recalled and replaced. Production problems were fixed before the Gen 2 guns were released. By far the biggest challenge with Gen 2 guns is prejudice.

Get an original Model 51.

I've got an original M51 on my short list.

Armybrat said:

Get an original Model 51.
View attachment 1041069

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I agree.

Nice!
I still have the original box too, but it has completely fallen apart. I like to get someone to restore it.