First off I'd like to say hi and that I'm horrible with introductions sorry if that not much of a first post opening. Now for the meat and potatoes.

I just picked up my R51 (sn is in the 5100's) at Gander Mountain today and before putting a live round through it I gave it a good cleaning and once over. Part of this included a check to see if it the hammer will drop out of battery and the answer is YES

After trying that out I decided to check what a primer strike look like on a piece of primed brass and boy was I shocked at what I found. After I worked the action and took the case out the the chamber the primer was bulging.

Next I decided a slightly more scientific approach was needed. So I removed the bullet and charge from 4 additional rounds of factory ammo and numbered them and took pictures of them. I then proceeded to fire them from my pistol and upon inspection all of these rounds looked like the first one. (All pictures will be uploaded at the end of this post).

At this point I was convinced that I did not want to fire a live round until I had a better idea as to what was going on. So I started to look over the barrel and breech block and made a unnerving discovery. The firing pin was pushing the round away from the breech block prior to having any resistance on the primer.

After discovering this I took a digital caliper and took case measurements and discovered that the primers stuck out about .012" past the base of the case. Exact numbers being: .008" for case #1, .015" for case #2, .019" for case #3 and .013" for case #4.

My theory on the "primer flow" issues is that the firing pin is creating a gap between the breech block and round just before detonation.

Others opinions and suggesting are welcome. I plan to call Big Green on Monday.
http://s1366.photobucket.com/user/Chuck ... slideshow/

Oh and here's a link to my video of the gab being made.
http://youtu.be/Rzsq6d4zjR8

Thanks for sharing chuck and welcome to the forum.

That is a very large gap.
Since my R51 is at Remington (Para) in NC for other repairs, I cannot check mine. When I do get it back I will be sure and look at this before I fire it.
Seems to me the only cure for that would be a new Barrel with a properly cut chamber.

Chuckdeuce wrote:First off I'd like to say hi and that I'm horrible with introductions sorry if that not much of a first post opening. Now for the meat and potatoes.

I just picked up my R51 (sn is in the 5100's) at Gander Mountain today and before putting a live round through it I gave it a good cleaning and once over. Part of this included a check to see if it the hammer will drop out of battery and the answer is YES

After trying that out I decided to check what a primer strike look like on a piece of primed brass and boy was I shocked at what I found. After I worked the action and took the case out the the chamber the primer was bulging.

Next I decided a slightly more scientific approach was needed. So I removed the bullet and charge from 4 addition round of factory ammo and numbered them and took pictures of them. I then proceeded to fire them from my pistol and upon inspection all of these rounds looked like the first one. (All pictures will be uploaded at the end of this post).

At this point I was convinced that I did not want to fire a live round until I had a better idea as to what was going on. So I started to look over the barrel and breech block and made a unnerving discovery. The firing pin was pushing the round away from the breech block prior to having any resistance on the primer.

After discovering this I took a digital caliper and took case measurements and discovered that the primers stuck out about .012" past the base of the case. Exact numbers being: .008" for case #1, .015" for case #2, .019" for case #3 and .013" for case #4.

My theory on the "primer flow" issues is that the firing pin is creating a gap between the breech block and round just before detonation.

Others opinions and suggesting are welcome. I plan to call Big Green on Monday.
http://s1366.photobucket.com/user/Chuck ... slideshow/

Which would mean that it's not an over-pressure event in the chamber. Interesting.

Peace favor your sword,
Kirk

-Electraclyde
Last night I was looking at the pistol with a dummy round loaded in the chamber and I noticed what appeared to be the same gap between the breech block and the backend of the casing that I observed in my previous post(this was observed via the loaded chamber indicator cut out). When I took a dowel and pushed on the round I saw the gap disappear. This leads me to believe that the headspace is off due to the chamber like you said.

I'll be calling Remington this afternoon and update accordingly.

-Deuce

Was the pistol assembled or apart? I'd like to try the same thing myself and just want to correctly replicate whatever you've tried. Also, *great* idea about testing with the primed cases!

Chuckdeuce wrote:-Electraclyde
Last night I was looking at the pistol with a dummy round loaded in the chamber and I noticed what appeared to be the same gap between the breech block and the backend of the casing that I observed in my previous post(this was observed via the loaded chamber indicator cut out). When I took a dowel and pushed on the round I saw the gap disappear. This leads me to believe that the headspace is off due to the chamber like you said.

I'll be calling Remington this afternoon and update accordingly.

-Deuce

Please do keep us posted. Mine has been a Remington (Para) in NC for almost 2 weeks. Have not he'ard anything from them yet.