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DonHowe
01-21-2022, 01:10 PM
Am wondering how others might go about this?
I have a 6.5x53mmR carbine for which I form cases from .303 British. Problem is, my chamber will accept a base dia. of .451". This rules out all brands of brass but W-W and R-P. Since R-P cases invariably collapse during forming that leaves only one option. Unless I can easily reduce base diameter by the required few thousandths...

Any suggestions?

MUSTANG
01-21-2022, 01:19 PM
DonHowe:

Perhaps you might try a similar approach to my addressing 7.62x51 Range Pick up brass with bases that expanded too much for chambering in some rifles. See this link; post #1 should give you the idea. https://castboolits.gunloads.com/showthread.php?430093-Oversize-7-62-308-Brass-Base-How-to-Correct-when-Small-Base-Dies-don-t-work&highlight=

Although the rim is the issue on your cases; I am sure this technique would work using a .450 sizer.

Winger Ed.
01-21-2022, 03:27 PM
You might try doing it in different stages sort of like the drawing process the factories use when forming new cases
instead of trying to do it all in one step.
I've also heard of guys doing this when going up or down making various brass from a parent cartridge
like making .25-06s from .30-06. they'd go to .270 first, then to .25-06.

I've had problems with GI brass fired from machine guns that have some rather 'generous' chambers.
For my situation I raised the sizer die up about 1/4 inch, ran everything through, then lowered it like normal,
re-lubed the cases, and ran them through a second time.

paul edward
01-25-2022, 12:16 AM
Did you anneal the R-P brass before resizing?
What brand of dies are you using?
Are you resizing in several stages or all at once?

DonHowe
01-25-2022, 03:39 AM
The R-P brass was not annealed.
The resizing was done in stages using various caliber dies. Trying to reduce the neck in a 7x57 die resulted in the case collapsing like an accordion at the shoulder. TNot being new to case forming and being stingy with brass I tried a gentler approach but with similar results. A bit of internet research turned up other similar accounts and since W-W cases formed without problems. Likewise with Norma, S&B, and PPU braSs tho they are all too large to chamber.

Using a .30x57 die to first move the shoulder back then 7x57 and 6.5x55 dies and some contortions I was able to form and fireform cases Before acquiring the proper C-H sizer die.

AntiqueSledMan
01-25-2022, 07:50 AM
Hello DonHowe,

I made a forming block to reduce .32 S&W to .32 Re-loadable Rimfire.
The S&W is .337" and the finished size of my cases were .3167" with no bulge to turn off.
I used a 1/2" block with 4 holes machined to the following diameters,
0.330", 0.325", 0.320", and 0.315". I pushed the case down to the rim in an arbor press,
then flipped and pushed out with a rod from the inside in each hole.
I didn't worry about closing up the primer pocket as I planned on drilling out for a .25 caliber nail gun cartridge for primer.
If I wanted to save the primer pocket, I'd use a punch with an extrusion to fit in the primer pocket.
I used a piece of 1018 Cold Rolled and did see some deformation after doing 100 cases.

AntiqueSledMan.

15meter
01-25-2022, 10:57 PM
If I recall correctly, even Ken Waters recommended Winchester brass for forming 6.5x53R.

I think he also recommended using new brass, not used.

I'll have to dig out my Pet Loads and verify that information.

I've only used new Winchester brass for forming and have had good luck.

I have no idea what would make Winchester work better. Left a little harder than the others so it withstands the forming better?

Phase of the moon?

Must be the tide.........

DonHowe
01-26-2022, 12:25 PM
I would love to have that Ken Waters info. Is that in the first Pet Loads?

Since I had no significant issues forming various headstamped brass I had to assume the R-P brass is softer. The only reason either US-made brass will chamber is that they are grossly spec diameter.
The only brass I have near spec is PPU at .457" ahead of the rim.

15meter
01-26-2022, 10:59 PM
I would love to have that Ken Waters info. Is that in the first Pet Loads?

Since I had no significant issues forming various headstamped brass I had to assume the R-P brass is softer. The only reason either US-made brass will chamber is that they are grossly spec diameter.
The only brass I have near spec is PPU at .457" ahead of the rim.

It's in the big red Pet Loads compilation. Was in the shed 3 times today and forgot to look.

Maybe tomorrow.

15meter
01-28-2022, 11:46 PM
And I've been back in the shed probably 8 times since the last post and not remembered.

Probably won't be tomorrow, boat's back on the ice:drinks:

skeettx
01-29-2022, 02:12 AM
I have an RCBS base forming set of dies.
They work great.
I use an RCBS A-2 press and lots of Imperial Sizing Wax
Mike

15meter
02-01-2022, 12:08 AM
Am wondering how others might go about this?
I have a 6.5x53mmR carbine for which I form cases from .303 British. Problem is, my chamber will accept a base dia. of .451". This rules out all brands of brass but W-W and R-P. Since R-P cases invariably collapse during forming that leaves only one option. Unless I can easily reduce base diameter by the required few thousandths...

Any suggestions?

Finally remembered to dig out the Pet Loads, it's under .256 Mannlicher, not 6.5x53R.

And yes, Ken Waters recommendation is to start with only new, un-fired W-W brass. He had trouble with the other makes of brass and settled on the W-W and even he had some losses while forming.

Good luck, I used new W-W and had very good luck, lost very few cases during the conversion process.

DonHowe
02-01-2022, 08:58 AM
Thank you for that 15meter!
As I was gifted this little carbine. For various reasons I had no desire to buy an expensive set of correct dies so determined to use what I have on hand. Once past the failed R-P experiment I only lost a couple od W-W cases, including both new and previously fired cases. My biggest hurdle was to get the shoulder back far enough to allow the bolt to close. To get that far took a piece of steel on top of the shellholder to push the case into a 6.5x55 FL die flush with the die bottom. Some cases still required some force to fully close the bolt on the empty case on the first chambefing. As I formed the cases in fairly easy steps I left annealing til the last step before assembling fireform loads.. At the end of this adventure I had a quantity of fireformed cases which fit the chamber perfectly.
I did find an old set of Pacific dies for 6.5x54. M-S but the FL die has a base dia. of about .444" so is useless but at least I got a seater die. More recently, a fellow shooter gave me a C-H 6.5x53r FL die with a case stuck in it. Got the case out as well as trashed decap/expander rod so now have a proper sizing die. If anyone wonders if a Mannlicher with questionable bore was worth all the gymnastics? HECK YES!

15meter
02-02-2022, 07:43 PM
I don't have any form dies, I just used the standard loading dies. I'll have to dig out my reloading notes for the .256.

I don't remember doing anything special to form cases.

skeettx
02-02-2022, 07:56 PM
DonHowe
You do not list your locale
Anywhere near Amarillo?
Sounds like an easy task for my equipment
Mike

15meter
02-03-2022, 12:43 AM
I don't have any form dies, I just used the standard loading dies. I'll have to dig out my reloading notes for the .256.

I don't remember doing anything special to form cases.

And was in the shed and dug out my notes on the 7x61 S&H, not the .256. Geezer memory.

DonHowe
02-03-2022, 08:40 AM
DonHowe
You do not list your locale
Anywhere near Amarillo?
Sounds like an easy task for my equipment
Mike

I'm way up north in (northefn) Indiana.

By the way, I could live happily ever after with Winchester brass if it were not for this current shortage mess.

15meter
02-03-2022, 08:04 PM
And I lied, what I did was a whole lot more complicated than I remember. It even appears that I made a whole write-up of the procedure that I posted somewhere on here.

Somewhere being the operative word.

My google-fu is failing me, I can't find the thread.

Almost positive that I posted it, it appears I cut and pasted into Word and then printed out a copy for my reloading notes.

15meter
02-03-2022, 08:08 PM
And bounced out of the forum, did a Duck-Duck-Go and came up with:

https://castboolits.gunloads.com/showthread.php?384845-303-British-to-6-5x53R-Dutch

Everything you ever wanted to know about forming .256 Dutch or .256 Mannlicher or 6.5x53R.

There has to be an English measurement version out there somewhere, like the 275 Rigby, those old boys couldn't have been satisfied with just 3 names. Especially Continental names.