Wow, after a great morning at the range with my gen 2 R51, (everything went bang and ejected).
I took it apart to clean it. Man, that slide spring is tough for an old  man's hands.
Guess what, the gun would  not go back together. I called Remington, talked to Justin Emerson
and he said send photos. I did, got a reply on the phone about an hour later. He is sending me
a shipping package with label for UPS. That was quick. Don't know what all the fuss is about
service.
     Anyway, while I was at the range, I shot Remington white box, WInchester USA Forged
with the iron casings, and Ruger ARX Polycase. All went bang.  Will get back with any thing
I find out from Remington.

I've disassembled and reassembled mine several times, but the last time I had the same problem. The slide locked up during assembly and it wouldn't move either way.  Wife called me for dinner so I went and ate and came back in an hour and it went right together.  Strange.

Wow, after a great morning at the range with my gen 2 R51, (everything went bang and ejected).
I took it apart to clean it. Man, that slide spring is tough for an old  man's hands.
Guess what, the gun would  not go back together. I called Remington, talked to Justin Emerson
and he said send photos. I did, got a reply on the phone about an hour later. He is sending me
a shipping package with label for UPS. That was quick. Don't know what all the fuss is about
service.
     Anyway, while I was at the range, I shot Remington white box, WInchester USA Forged
with the iron casings, and Ruger ARX Polycase. All went bang.  Will get back with any thing
I find out from Remington.

As stated tis morning, I got my R51 back together. I did not send it in to Remington. That would just slow down work on other
shooters who want their guns back. Has anybody else tried Winchester USA Forged steel case ammo?

I haven't tried the brand you mention, but do have some Tula steelcase, but I am reluctant to try them through a small handgun like the R51.  Maybe through my Beretta 92FS or CZ75BD would be ok.

Valvestem, I too do not care for Tula ammo. But I have shot Winchester USA Forged in most of my 9MM firearms, including my Walther P-38. They all like it. The only problem
is gun ranges that believe all steel case ammo has steel core projectiles. They are afraid of "Sparks". Hard to convince them that the WIN ammo is lead core, even after
reading it on the box. Plus they do not like steel casings. Simple to bring a magnet on a string and pick up your casings, then toss them. I won't get into reloading steel
casings, as I know nothing about reloading, and at my age, do not need to reload.  :=}   

1911 shooter that happen to me twice and what I done was turn the pistol upside down and tap on the slide and the breech block (I think) because of the oil or gun greese stop it somehow ,,, and all so the slide will stick & stop and will not move ,were u slide the pin goes in and to move it  pull the trigger. it unlocks it and u can rack the gun