Hey all,
I have found this post very enlightening...thanks to all that contributed!  So...spec’d out the dimensions of my two factory mags that came with the purchase last June.  After reading the various posts I expected weirdity...but this is amazing.  Below are the dimensions I got

Mag dimensions
                         Mag 1.            Mag 2
Lips (Rear)      0.361          0.359
        (Front)     0.354             0.334

Width
(Top rear)         0.594             0.595
(Top front)        0.585             0.586   At follower groove
(Bottom rear)    0.590            0.590
(Bottom front)   0.584            0.585

Although the box dimensions are within a thou, the lip dimensions are radically different between these mags and of course the reverse taper y’all pointed out is there...extreme in Mag 2.  The retainer tab is pronounced and is in need of some judicious grinding and polishing.  No surprise, Mag 2 was a worse troublemaker than Mag 1...lots of nose diving and hang ups on the tab, especially with +P hollow points.
But, that’s not the most remarkable find...the mag spring dare suffer to between the 2 mags. If this works an I can post a pic you can see the mag 2 spring is one coil less than Mag 1 and it was a really contorted profile.   On top of that the Mag1 spring was in backwards not in line with the angle of the follower...was this what folks got with the gen 1 guns.

Got something for you...I saw on another thread (sorry couldn’t find it again when I looked to quote it) y’all were talking about trying. Believe it was a SW spring in the mag... well that got me looking an I found the Glock 43 Mag spring is almost identical to the R51. See image
Got them from Ghost Inc
https://ghostinc.com/glock-43-plus-15-magazine-spring/
I picked up a 3 pack for $8.  They are a plus 15% strength...has 14 coils
Only thing I did was trim a little bend from the bottom base coil that interfered with the magazine bottom.  Fits fine, no problem loading 7 rounds and it seems to me that the rounds maintain the proper angle with the follower.
Loads  fine cycling by hand...
So this might be an option...will try live once I get time to fix up the lips on the mags and can get to the range...will be a little while.
Hope this is of interest
John

John thanks for the post...
Given the spring situation, gotta wonder if either of those mags were "new" when you got them.
I was concerned only with the width of the mag at the ridge because that was the only dimension I wanted to adjust... Joe

Oh, for 5hose interested... the Glock springs spec out 0,0433” dia stock and the rem springs are 0.0423...
J

Nope, that makes sense.  I have noticed the rounds don’t lay flat inside the mag too. I’ve jus been setting to the back and one side withe a smack and they seem to stay in line...whether they stay 5hay way in use...got me.   We’ll see how it goes.
Take care
John

Interesting ... makes sense on their part...but if they want to go that route they need to lose the plastic base cap and follower...I’ve only put about 300 reds through mine and the drop surface of the follower shows scoring which I diligently polish off when cleaning.   So the 45 makes a good go-no go gauge...nice!
Will use that approach. Thanks
John

Well here’s an update.. Remingtonreplied to the emai I sent and asked me to call em...I had filled them in specifically on th different springs that were in my various mags.  Fellow I talked to was nice enough, but didn’t know much about guns...he couldn’t answer me on how many coils should be in 5he magazine spring and said he would have to check with engineers...but he is sending me two new mags and said that they would be checked out ...will not be surprised to get two new bubbl e packed mags that no one looked at!  Regardless, at least we know how to fix em.
Have a good weekend folks
John

swaits -  Great report on the new mags - perfectly parallel!

I seriously thing that between REM and their contractor, the specifications on the magazine lips got reversed.  Big Green has a history of screwing things like this up, they totally dorked up the chamber of the 6.8SPC too. 

The good news is easy fix!.  I'm going to try some of those glock springs.  If they reduce the friction in the magazine while still having enough energy to force the last round into up into place, so much the better.  We may have this thing solved.

Sorry about resurrecting a dead thread.  Catching back up after some time away.  Good work guys!