R51 Gen 1

[Indyman]

Does anyone know where I might find a R51 Gen 1 for sale? I'd like to study and catalog all the changes Remington made ...  Thanks!

[R51Fan2017]

Does anyone know where I might find a R51 Gen 1 for sale? I'd like to study and catalog all the changes Remington made ...  Thanks!

Unfortunately, you are going to have a tough time doing that. Most all of the Gen1 pistols were sent back for rework after the disastrous release in 2014. If there are any remaining, (which there is probably a handful) the owners may or may not be easily persuaded into selling them. I wish I had a Gen1 in my collection!

[Indyman]

I realize that. If I can't find one for sale, maybe someone would let me examine one in their collection .... either way, I think it would be useful to document the changes between the Gen 1 and Gen 2 guns. Thanks!

[R51Fan2017]

I realize that. If I can't find one for sale, maybe someone would let me examine one in their collection .... either way, I think it would be useful to document the changes between the Gen 1 and Gen 2 guns. Thanks!

By all means! Someday, collector's 50 years from now may be interested in these little guns. The more info gathered now while it is more readily available, the better! If I run across one, I will be happy to let you know.

[funflyer]

I think it would be useful to document the changes between the Gen 1 and Gen 2 guns. Thanks!

I remember seeing something about all the changes, either on youtube or another website. I just can't remember where.

[sebvox]

The next best thing to owning a Gen 1 is downloading the 3D model in "World of Guns".  The model is the Gen 1 so you can examine all the parts there.  There are a couple videos out on the tube that show the R51 3D model.

These are the changes between Gen 1 and Gen 2 that I have come up with so far:

• Gen 1's were manufactured at the Para USA plant in Pineville, NC marked "Charlotte, NC" until March 2015, eight months after the July 2014 recall.
• Gen 2's still marked "Charlotte" are remanufactured in the Huntsville, AL plant to receive the below listed revisions.  Starting in 2017 newly manufactured frames are marked "Huntsville, AL" and have the "H" prefix in the serial number.

• Gen 1's had the R51 logo rearward next to the slide serrations.  A larger pocket was milled in the slide for the hump on the breach block.  Complaints of rough racking.
• Gen 2's have a redesigned slide with the R51 logo forward near the ejection port to differentiate the New from the Old slides.  The new slide now has an FNC finish and smoother function.  Milling on the new slide is slightly different behind where the slide meets the breach block ramps.  Not sure what this is for as it is in a non-contact area.  A smaller pocket is milled in the slide for the hump on the breach block.  The action is considerably smoother.  The Huntsville plant used Hardinge Bridgeport GX300 VMC milling machines for slides.

• Gen 1's had a thin, flat magazine base plate known to deform.  Unmodified magazine weighs 1.7 oz.
• Gen 2's have a thicker, rounded base plate with the addition of a "ramp" on the follower.  It is still necessary to trim the legs of the follower yourself for proper operation.  Modified magazine weighs 1.8 oz.

• Gen 1's had a smaller, shorter disconnector.  The top of the ears are taller than the new disconnector.  This could account for some rough racking.
• Gen 2's have a longer disconnector to address trigger reset issues.  The pistol frames are milled to accommodate the new disconnector, therefore a new disconnector is not compatible with a Gen 1 frame.

• Gen 1's had an ejector that was stationary and had a larger profile.
• Gen 2's have an ejector that pivots/lifts and has a smaller profile.

• Gen 1's had a cadmium plated action spring (around the barrel) that was shorter, bushing was known to become scratched on exterior. The spring wasn't strong enough to put the slide back into battery, in some cases.
• Gen 2's have an action spring that is longer and PTFE coated in blue, bushing is replaced with a hardened chrome bushing.  The spring is stronger now and the demonstrated 1-finger racking is gone now.

• Gen 1's had a breech block that caused racking issues and cartridge deformation.  The magazine also interfered with the breech block when inserted.
• Gen 2's have a redesigned breech block with a notable haunch added for a larger surface to place the cartridge in battery (to help with nosedives and casing deformation).  The bottom deck was raised/lowered to not foul with the magazine.  There is a bevel on the leading edge and an eased out area near the extractor neoprene pad.  The extractor is redesigned to have a shorter claw for precise engagement.  The extractor is also slightly longer and the neoprene pad is moved rearward. The neoprene pad is now light green instead of black.  The barrel was redesigned to remove the "wings" on either side of the feed ramp.  The locking grooves on either side of the barrel, where the slide locking pin goes through, were reduced.

• Gen 1's had grip screws that were known to become loose.
• Gen 2's have a larger rubber O-ring that replaced the smaller O-rings at each screw as a lock ring.

• Gen 1's had front and rear sights that were known to drift loose from the dovetail groove, on some models.
• Gen 2's have stock front and rear iron sights that were redesigned to have a set screw to hold them in place, with the exception of using the fiber optic or tritium sights.

• Gen 1's had the sear pin, upper manual safety pin, and magazine catch pins that were known to drift loose, on some models.
• Gen 2's have the redesigned knurled pins that were replaced to stay driven home.

• Gen 1's slide catch pin is slightly shorter (0.9240 in/23.47 mm) and cannot be removed without the use of a helper tool.
• Gen 2's slide catch pin is slightly longer (0.9535 in/24.22 mm), when installed it sits proud of the frame and can be removed with the push of a finger.

• Gen 1's weigh 20.7 oz. without magazine.
• Gen 2's weigh 20.8 oz. without magazine.

Feel free to add and list other changes.

[scouts owner]

I own a Gen 2 that is marked Charlotte.

[sebvox]

Yes, scouts owner, you are correct.  My statement says "Gen 2's were remanufactured... in Huntsville, AL".  So the leftover Charlotte parts were sent to Huntsville for Gen 2 re-manufacture and re-assembly. 

[sebvox]

I have updated my list of changes between the Gen 1 and Gen 2 in the previous post.

[R51Fan2017]

Very well documented with pictures sebvox! Thanks for the effort to get that posted. That should be stickyed by the moderators! HINT HINT.

[sebvox]

I made a video that shows the differences in the Gen 1 vs the Gen 2.  I show the R51 operation in slow motion so you can see how it works.  Be kind, it was my first video on youtube.

https://www.youtube.com/watch?v=D_oAMuKg4CQ

[R51Fan2017]

If anyone is interested, there is a Gen 1 for sale on Gunbroker https://www.gunbroker.com/item/875162865

A cool listing for sure. It's kind of shocking to see one still left in the wild. Some collector needs to scoop it up.

[springfield art]

Thanks for this info! My R51 has been apart for months now, just put it aside for a while. Will have to refer to much information just to re-acquaint with it.

[sebvox]

What's it apart for?  Are you planning on making some mods?

[springfield art]

Nah. Just got into other busy stuff. Have the after-market trigger, don't know if I want to put it in or not. Tiny little spring in there threw me off. Thanks.