Rolling Block headspace question - and video

[H Wally]

What do you guys think of the headspace/gap on this rolling block rifle? I've never had one that was functional, and don't know if this is acceptable to shoot. It seems a bit excessive to me, but I don't know if this is normal or what...

Without a cartridge:
-With hammer fully back block wobbles side to side a fair bit and block forwards and backways slightly without rolling on the bearing.
-With hammer at half #### there is still some side to side wiggle and when pressed, block will shift back.
-With hammer dropped there is less side to side wiggle, and block will shift back when pressed.

With a cartridge in place:
-With hammer fully back the block wiggles side to side slighty, but there's no forwards or back wiggle
-With hammer at half #### there's no side to side or front-back wiggle.
- With hammer dropped there's no wiggle in any direction.

Gun in question is a Remington action with Gew 71/84 barrel.

 

[green]

Looks like a shot gun action. Scallop on top of receiver ring and narrow hammer nose.

 

[762mm]

Yeah... I think you're right to be concerned. I have a Remington Rolling Block in 50-70 and there's definitely no such gap between the block and the chamber. It closes shut and makes full contact with the receiver, with minimal play.

I guess yours might've been modified to allow for the rounded head of a .43 Mauser round...? This might explain the gap, but is definitely not a testament to its' safety. On that note, I wonder why someone would rebarrel an antique rifle with hard to get brass to another antique hard to get caliber... It seems like .44 Special or .44-40 would've been a much better candidate if you're going to put the work into it... Puzzling.

Bottom line, I'd say it definitely doesn't look very safe and the block might disconnect and shoot through your eyeball/head when fired.. but then again, I've been wrong before. More knowledgeable Remy RB owners will probably pitch in their opinions shortly.


P.S. While doing some online research on these rolling block rifles, I've come across some pictures of what happens when the block fails in one of these... not a pretty picture and some shooters in Europe have been seriously injured/killed, apparently (due to metal fatigue combined with the use of improper loads). Be careful...

 

[H Wally]

Looks like a shot gun action. Scallop on top of receiver ring and narrow hammer nose.

I'm not too familiar with them. Any other actions have the groove along the top of the receiver ring? Also, by narrow hammer nose, do you mean narrow from side profile or top profile?

Yeah... I think you're right to be concerned. I have a Remington Rolling Block in 50-70 and there's definitely no such gap between the block and the chamber. It closes shut and makes full contact with the receiver, with minimal play.

I guess yours might've been modified to allow for the rounded head of a .43 Mauser round...? This might explain the gap, but is definitely not a testament to its' safety. On that note, I wonder why someone would rebarrel an antique rifle with hard to get brass to another antique hard to get caliber... It seems like .44 Special or .44-40 would've been a much better candidate if you're going to put the work into it... Puzzling.

Bottom line, I'd say it definitely doesn't look very safe and the block might disconnect and shoot through your eyeball/head when fired.. but then again, I've been wrong before. More knowledgeable Remy RB owners will probably pitch in their opinions shortly.


P.S. While doing some online research on these rolling block rifles, I've come across some pictures of what happens when the block fails in one of these... not a pretty picture and some shooters in Europe have been seriously injured/killed, apparently (due to metal fatigue combined with the use of improper loads). Be careful...

That's what I'm concerned about - my only other RB I've owned had cracking on the bottom of the receiver ring and on the block.


As for the rounded 43 mauser head - I think that's what's A) not allowing it to close flush and B) keeping the action tight.

Anyone think that cutting a rim recess and lengthening the chamber accordingly would solve the headspacing if the block was fixed simultaneously?
Would it be worth it?
Is this action a shotgun action? Is it even capable of handling being chambered for this new cartridge?

 

[camerl2009]

it could vary well be a RB shotgun action hmm id put a new barrel on it and start over or have a good gunsmith look it over

 

[apu]

I gotta echo 762 sentiments, as my 50/70 roller also has the block completely close on the chamber with a loaded round, no play is involved. Your setup may work but it really looks suspect .

 

[H Wally]

Ok, I'm thinking of possible solutions that would allow me to keep the gun, and before proposing it to my gunsmith I'm wondering if you guys think it's viable.

I'll explain my background logic and then proposal for solution:


Looking at pictures of Rolling Blocks on the net, it looks like some RB barrels/breech faces are supposed to protrude from the receiver ring slightly in order to sit flush with the block, which is set back from the receiver ring. It also seems that the barrels are cut with rim recesses for the cartridge, instead of leaving the cartridge rim exposed like on some bolt actions.

My gun has no rim recess. Because of this, the barrel is set forward in the receiver, to give room for the rim to fit between the barrel and the rolling block. Since the 43 Mauser has a very thick recessed rim, it means there's an even larger gap than would normally be expected.

*** Note that the rolling block itself has a gap between the receiver ring and the face of the rolling block, BUT this gap and block face is parallel to the breech face and receiver ring, so I suspect the wear is not as heavy as suspected.
If it were actually heavily worn it should not sit parallel to the receiver ring.

SO

Would it work to move the barrel back in the receiver ring until the exposed barrel/breech face took up the gap currently in the action and sat flush against the block?
I understand that for this to work:
- The barrel woud need to have a recess cut for the case rim so that the barrel could fit flush against the block.
- The chamber would need to be recut slightly because of the extra depth the cartridge would enter with it's new rim recess.


Does this sound like it would work? Is there a better way? The gun has been shot a fair bit as is, so I'm not worried about its integrity, just figuring out how to refine the setup.


Here you can see how other RB actions have their barrels protruding out of the rear of the ring. They show both the exposed barrel/breech face AND rim recesses, both of which are absent on my gun:

 

[762mm]

Seems like a plausible scenario that would probably work... but you're still best to consult a gunsmith before going ahead with this little project, IMHO. Don't forget that the .43 Mauser steel you're playing with is probably as old as the rest of that gun, or nearly as old.


As far as I'm concerned, the collector value of the gun is screwed anyway, so if you're going to go into extensive modding... why not consider getting a new block if this one is shot (there are places in the States that sell them online) and rebarrel to something like a new .44 spl or .38 spl ?

Although the collector value might be gone, shooter value would increase if you made it into a more reloader-friendly setup. That, plus I believe any of those two revolver rounds has much lesser pressures than .43 Mauser does, which makes the gun safer overall.

 

[mooncoon]

Since last we talked offline, I am coming to wonder if whoever put the barrel in, bought one with a chamber but no rim recess. That may be why the rim sits outside the barrel. If my supposition is correct, you may find after firing the rifle, that the shoulder on the shell has moved forward by about .065". Regardless I don't think you need a new block but rather may need new pivot pins and can also move the barrel back one thread and cut a rim recess as appropriate

cheers mooncoon

 

[H Wally]

Seems like a plausible scenario that would probably work... but you're still best to consult a gunsmith before going ahead with this little project, IMHO. Don't forget that the .43 Mauser steel you're playing with is probably as old as the rest of that gun, or nearly as old.

As far as I'm concerned, the collector value of the gun is screwed anyway, so if you're going to go into extensive modding... why not consider getting a new block if this one is shot (there are places in the States that sell them online) and rebarrel to something like a new .44 spl or .38 spl ?

Although the collector value might be gone, shooter value would increase if you made it into a more reloader-friendly setup. That, plus I believe any of those two revolver rounds has much lesser pressures than .43 Mauser does, which makes the gun safer overall.

I mainly bought the gun because it is chambered in the same cartridge as my gew 71/84, hence the benefit of having the same reloading components. I don't plan to push the gun, as I don't like to stress any of my antiques. Overall I'm happy with the caliber of the gun, as long as it's safe. Were I to make my own setup I would certainly go with a more common caliber though.

Since last we talked offline, I am coming to wonder if whoever put the barrel in, bought one with a chamber but no rim recess. That may be why the rim sits outside the barrel. If my supposition is correct, you may find after firing the rifle, that the shoulder on the shell has moved forward by about .065". Regardless I don't think you need a new block but rather may need new pivot pins and can also move the barrel back one thread and cut a rim recess as appropriate

cheers mooncoon

The maker of this gun used a Gew 71/84 barrel - still has the german proof markings, front and rear sights, extractor notch etc. From looking at my original 71/84 I can attest to the fact that original 71/84' dos not have a recessed rim either, but were made so that the rim sat against the breech face and was surrounded by the bolt head, rather than sitting in a rim recession flush with the bolt face against the flat face of an enfield style bolt face.

As it stands it seems safe enough, mainly what surprised me was the gap present around the shell (caused by lack of recessed rim), however it does not seem there is any portion of the case wall that would be unsupported by the barrel, and there is only the slightest sliver of a gap between the base of the cartridge and the block face.

 

[green]

The RB shotgun hammer was narrower in the side profile to clear the 20 guage shell.