7 MM Rolling block -fire forming cases?

[broomhandle]

Hi Fellows,

I have a nice old 1902/10 Remington rolling block I want to shoot. I'm told the chambers are made oversize like the Mauser rifles of the same period. I have about 50 once fired 7 mm Remington cases.
I have been looking over the net for how to case form the cases. I know you can use cream of wheat & a plug of wax with 5 to 10 grains of Unique.... should the wax be a 1/16 thick or fill the whole neck?
I guess, I'm looking for someone's tried & true method.

I have also read that by seating a cast bullet to the lands using a 8-10 grains of Unique should also do the job. Does one work better then the other?
That load is the so called "universial" cast bullet load & low pressure too I have not found a source that really spells it out to a newbie fireformer.
My thought is the cream of wheat would develop less force to form the case. BUT, I have no idea if the bullet method is over kill!
Because we are told not to seat bullets in the rifling, because it increases pressure.

As you can tell, I know nothing about fireforming, except what I have seen on the web. And like anything else, there can be more then one way to get good results.

Thanks for any & all help,
broomhandle

[bgoff_ak]

i've tested CoW in .44, but there was some talk about not doing this in a shoulder case. if you want you can also cast your chamber to see what it looks like. i did some pre forming in my .338, but shortly after that your weighing primers doing case vol calcs and sorting piles of bullets into .01 bins. I'm sure some one here will chime in on CoW and that chamber. also if you want to go down that road mark the top of the brass so you know the proper orientation when you re-chamber it ( assuming your just going to neck size )

[broomhandle]

Hi bgoff_ak ,

Yes, I read some reports of damage to the barrel if the COW forms a plug or pressure spike.

I found another method! This one seems to make sence to me.
I run the sizing stem from a 30 cal into the 7mm cases. This enlarges the neck. Then I run the case back into the 7 mm die until it just fits the chamber. This makes a false neck bump. Which allows the case to blow out the small amount it needs to fit the oversize chamber.

Thanks for the reply,
broomhandle

[lmcollins]

Your old rolling block is a rimmed cartridge.

This means that you need rimmed cases, and a number 26 RCBS shell holder. You have a 7x57R. The dies are the same, but not the case.

Make a false shoulder by necking up your NEW 7x57R cases, and then neck them down to a crush fit in your rifle. After this, load and seat as in a standard 7x57.

Try someone like Huntingtons for both the cases, and the shell holder. They will make certain that the case and the shell holder go together.

Good luck.

[broomhandle]

Hi Imcollins,

This rifle is marked 7 mm Mauser there is no step on the barrel for the rim!

Do you have a method of adjusting the false shoulder, so it forms on center.

Thanks for your reply,
broomhandle

[Reverend Al]

I have to agree that I like the "false shoulder" method to fire-form cases to the chamber the best. If you take new, factory cases and fire-form them with or without a filler then you are usually stretching the base of the cartridge forward until the shoulder reaches the front of the chamber and weakening the base of the case on the very first firing. If you create a false shoulder and then carefully adjust your dies to push the false shoulder back just enough to contact the front of the chamber then your cases will form perfectly without stretching the bases and weakening the brass. Using a boolit hard seated into the throat works well too, and it pushes the case back hard against the bolt face and again the shoulder will blow forward to fit the chamber, rather than stretching the base forward to fit. My personal preference is still the "false shoulder" method ...
69837

[gandydancer]

I must be missing some thing here? if its a 7mm Mauser is that not a 7X57 mauser? if so why not just buy some brass or ammo?? GD

[broomhandle]

Hi Gandydancer,

The (Cock on closing) Mauser rifles along with the British 303 Enfields & Remington rolling blocks of that era, had extra large chambers to allow for dirt & stuff in combat.
A jammed rifle in combat, is a truly scary thing, to experiance. Now with better, cleaner powders, stronger extractors & better brass it is less of a problem.
7 mm Brass is expencive & my aim is to prolong case life by fireforming the cases to the rifle (better accuracy) & shoot only light loads in this type of rifle.

Thanks for your intrest,
broomhandle

[broomhandle]

I have to agree that I like the "false shoulder" method to fire-form cases to the chamber the best.
Reverend Al

Hi Sir,

Can you explain your method of making that false shoulder? I'm not having good results with my first attempt. As I mentioned in another post.

Thanks,
broomhandle

[country gent]

Anneal the case necks beforenecking up to 30 caliber then back to 7mm. I have fire formed brass with just bullseye powder no fillers or plugs but you have to keep the case pointed up the whole time. A wax plug will hold everything in place dacron fibers will do the same. A cast bullet load works great and you can get rough zeros and a start on loads. Start low and work up to a formed case. A chamber cast will give you an idea what you need to do and when cases are fully formed. When I had a rifle rebarreled the stub leftover was cut to 1" and the neck shouldeer cut with the reamer and the neck bored reamed out .010+. This gave me a gage I could mesure headspace with. Wasnt an actual measurement but a comparative measurement. I could know when I was bumping the shoulder back .001-.002 easily. A simple gage could be made from cold rolled steel with a lathe and small boring bar.

[broomhandle]

Hi country gent,

So I just dump the charge of Bulleye (10 grains?) into the case hold it up & fire? Or same charge with a tiny tuff of dacron or toilet paper?
Please understand, I am a TOTAL newbie at this & it appears that like many other things on the net. There are conflicting ways to do the same thing.

Thanks for your reply,
broomhandle

[Reverend Al]

Hey Broomhandle!
No problem ... Again, I really prefer this method for forming brass to get correct headspace especially on guns that tend to have big, long, "sloppy" chambers like military .303 Brits, Mausers, etc. I must admit that I have the benefit of a couple of long and very gradually tapered neck expanding rods that fit onto a standard RCBS threaded die rod, and after annealing the case necks to prevent splitting as they are expanded you just put a bit of case lube inside the necks and slowly and steadily run the cases up over the tapered expanding rod to bring the neck up to a larger than standard size. (For example from 7mm up to about 30 calibre) At that point apply a bit of case lube to the outside of the cases and with your 7mm Mauser full length sizing die set high up off the shell holder start pushing the "false shoulder" back down to a 7mm neck and shoulder again. Adjust the sizing die to push the shoulder down in very small increments until the cases will JUST chamber and close the bolt with a bit of effort needed. You now have your cases fitted perfectly to YOUR chamber regardless of whether it has a bit of excessive headspace or not. Once you fire form the cases with your first loading do NOT push the shoulder back again or you are back to square one all over again! If you can afford the luxury, having a "neck sizing only" die is the ideal way to resize your fired cases that are now perfectly formed to your individual chamber and keep that ultimate fit repeatedly ...
Good luck with your project!
Rev Al

[broomhandle]

Hi Fellows,

I would like to thank all of you for your help & replys to my newbie questions.

Reverand Al, I have a really nice long tapered expander in .310 that will be just the ticket. I'll give the local reloader supply guy a call in the morning & try to pick one up about .305. I'm guessing the annealing step will help to allow the cases to form on center.

Thanks AGAIN to all of you,
broomhandle

[lmcollins]

7x57 and 7x57R

They stopped making the rolling block in something like 1905, and I don't think that ANY of those old rifles were ever made for anything but rimmed cartridges. The extracter only backs the fired cartridge out of the chamber a bit. It has to be removed by hand.

I think that the rear of the case fits between the back of the breech and the face of the block. This is how the headspace is determined. If it is the original barrel it is just marked 7mm. Think of it like matches: in the old days, you didn't have to say, "Strike to light." Everyone just knew that.

If you use your present cases you'll have to poke them out with a ramrod.

[L Ross]

7x57 and 7x57R

They stopped making the rolling block in something like 1905, and I don't think that ANY of those old rifles were ever made for anything but rimmed cartridges. The extracter only backs the fired cartridge out of the chamber a bit. It has to be removed by hand.

I think that the rear of the case fits between the back of the breech and the face of the block. This is how the headspace is determined. If it is the original barrel it is just marked 7mm. Think of it like matches: in the old days, you didn't have to say, "Strike to light." Everyone just knew that.

If you use your present cases you'll have to poke them out with a ramrod.

I respectfully beg to differ. I have owned two 7m/m Spanish Mauser rolling blocks, still own and shoot one, and they were made for the rimless cartridge. Both leave a funny looking double neck when fired. I take great care not to resize the case beyond the first step in the neck. Indexing the brass also helps. I usually shoot a 160 gr cast bullet with 14.0 grs of 4227.

Duke

[broomhandle]

Hi Imcollins,

This one is just a standard 7mm Mauser. The extractor on this one pops the case out with great vigor!

The Rolling Block rifles in standard 7 mm Mauser was sold to about 12-15 countrys depending on the source.
It was used in many cases into & after WW-1 for various dutys including training schools.

I could find no listing of Remington Rolling Blocks made with a 7 mm rimmed case. The only listing I found, was that some were made for various drillings & combo. rifle/ shotgun guns. Their main use was for game driven hunts, that were popular in the late 19 century & early 20 th century. The drivers might scare up a deer or a bird ,so you have a barrel ready for what ever popped up.
The rimmed case is neat looking, I will look for one at the big collectors show in Tulsa next time.

Best,
broomhandle

[broomhandle]

Hi L Ross,

Would it be possiable for you to drop me a PM with all the loads you have found that work well in your RRB 7 mm Mauser rifle?
OrPLEASE send me a link!
I'm looking all over the net & only found three or four. I think, I will only be shooting cast bullets out of this one.
It's about 103+ years old no need to push it! I have a sweet Ruger #1 in 30-06 that will do all that a single shot rifle in North America can be expected to do.

Best to you,
broomhandle