resizing .32-20 to .25-20...problem

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24 January 2020, 22:30

Tyke

resizing .32-20 to .25-20...problem

Given the fact that .25-20 brass is all but impossible to find, unless you willing to spend a lot of money to buy .25-20 ammo at $70.00 a box, I, like most folks, decided to try necking down Starline .32-20 brass to .25-20 and found that the two cartridges are two different animals.
Several problems existed.
Primarily,he diameter of the .32-20 at the web of the case is .3517 (SAMMI). The diameter of the .25-20 is .3465. The .32-20 ase os .0052 larger and hence won't chamber in a .25-20 rifle (92 Win).
My question is...has anyone else run into this problem..?

25 January 2020, 04:02

Stonecreek

Starline seems to be using some odd dimensions for their brass. A number of shooters who have Sako .222's found that Starline brass is difficult or impossible to chamber in some Sako .222's. I happen to have several Sako .222's and found that two of five (both of them early ones) would not chamber Starline brass. However, both of these rifles easily chamber any and every other brand of .222 ammunition or brass.

I suspect that if you were to try some Winchester or Remington .32-20 brass you would find it compatible with your rifle. I just measured a bunch of WW and RP .32-20 brass and both measured an average of .347" just in front of the rim. My RP .25-20 and .218 Bee brass is a tad smaller at .343-.344". Just for giggles I'll try reforming a .32-20 to .25-20 and report on the result when I get the time.

25 January 2020, 05:08

bpesteve

I've been sizing starline 32-20 into 25-20 (and even from there to 218 Bee) for a couple of years now with no problem, at least in supplying my old Marlin '94 (and Win m43) with ammo. I have a selection of 32-20 and 25-20 brass here, I'll measure several at the head and also report back.

26 January 2020, 06:51

bpesteve

Some 'family' case head diameter measurements:

.350" - old R-P 32-20
.350" - W-W 32-20
.350" - old old headstamped "WRA Co 25-20 Marlin"
.348" - current Starline 32-20
.347" - older Western 25-20
.347" - older W-W Super 218 Bee (convex primers)
.345" - more recent W-W Super 218 Bee (white box unprimed brass)
.345" - current Hornady 218 Bee unprimed brass
.344" - most recent (still current, I think) R-P 25-20 factory ammo

26 January 2020, 22:49

Tyke

Even SAMMI suggests that the two cartridges are different in several ways and given that I just installed a new liner in my Win 92 and used a new Clymer finishing reamer I guess I'm stuck with a tight chamber.
I've pleaded with Starline along with many others that they produce .25-20 brass. My words appear to have fallen on deaf ears.

27 January 2020, 00:20

Atkinson

Perhaps you need a stronger press and perhaps a 25-20 file trim die to assist your operation..??

27 January 2020, 18:46

cgbach

I am doing exactly what you are trying to do. I am forming .25-20 cases for a Winchester M53 using Starline .32-20 brass. What I ended up doing was making a forming die that uses a series of collets to form the neck and shoulder. The final step is a pass through the f.l sizing die. Occasionally I will get a wrinkle in a shoulder but if I am careful with the lube I can minimize this problem. Is your f.l. die not sizing the head enough or do you have an exceptionally tight chamber?
C.G.B.

29 January 2020, 02:31

Tyke

My press is an RCBS Rock Chucker.
It must be remembered that the shell holder eats up .050 of the shell base thus prohibiting "full length" resizing/reforming.
There's no way around it that I can figure.
A .32-20 case base is .347 and a .25-20 base is .343. That .004 at the case base can't be squeezed down!

Trimming the case length would not help. It's the BASE diameter that is the problem...for a new chamber.

Also,the case measurements I'm giving are Rem. 25-20 cases and Starline .32-20 cases. It is the Starline cases I can't reform satisfactorily.

29 January 2020, 06:36

Stonecreek

Please clarify something: Do factory .25-20 cases chamber in your relined/rechambered rifle? If not, then perhaps the chamber is undersized.

01 February 2020, 03:37

Tyke

quote:
Originally posted by Stonecreek:
Please clarify something: Do factory .25-20 cases chamber in your relined/rechambered rifle? If not, then perhaps the chamber is undersized.

Yes. They chamber perfectly. They are R-P .25-20 reloads.
I mic'd the chamber mouth: .3505
SAMMI chamber............: .3502
R-P .25-20 unfired case..: .3543
Resized .32-20 Starline..: .3548

These measurements are at the case base.

01 February 2020, 03:44

Tyke

I "painted" the resized .32-20 with DYCEM blue and it appears that perhaps the Lyman resizing die is not resizing the .32-20 case down sufficiently. There are quite obvious severe marring in the area of the resized .32-20 body!!
So, having said that, perhaps it is not a "base" size problem but a body size problem. I'll have to try and locate an RCBS .25-20 sizing die and see if that solves the problem.
Frustrating!!!!!!!!!!!!!!!!!!!!!!!
Any body got a .25-20 sizing die for sale????

01 February 2020, 04:51

Hipshoot

Have you tried sizing .218 B cases up? Hornady makes the B cases or at least did a couple of years ago.

Hip

01 February 2020, 17:32

hogfarmer

quote:
Originally posted by Tyke:
My press is an RCBS Rock Chucker.
It must be remembered that the shell holder eats up .050 of the shell base thus prohibiting "full length" resizing/reforming.
There's no way around it that I can figure.
A .32-20 case base is .347 and a .25-20 base is .343. That .004 at the case base can't be squeezed down!

Trimming the case length would not help. It's the BASE diameter that is the problem...for a new chamber.

Also,the case measurements I'm giving are Rem. 25-20 cases and Starline .32-20 cases. It is the Starline cases I can't reform satisfactorily.

You can reduce the thickness of the shell holder to allow the die to size a little lower. I had to do this for a tight chambered rifle once.

01 February 2020, 21:28

Tyke

Wouldn't raising the case up higher in the die produce a shorter case body and a longer neck?

I really didn't want to get into a conglomeration of cases (I.E. .218 Bee) which can also be hart to find.

I'm going to try a different set of resizing dies (RCBS). Maybe these LYMAN dies were made on a Friday!?

02 February 2020, 20:35

Stonecreek

Have you measured the diameter of the neck of the Starline loaded rounds? It is possible that after sizing down to .25 the necks are too thick and it is at the neck where your ammunition is too large for your chamber, not in the body or base.

02 February 2020, 21:13

hogfarmer

As I had some virgin Starline 32-20 brass around, I took my RCBS dies and formed a few 25-20 cases. They measured .346 at the base. As I used dial calipers, probably not overly accurate but close enough. I made up some dummy rounds using 86 grain jacketed bullets and they fed and chambered perfectly in my Winchester model 92.

Obviously this is only one example, so take it for what it's worth. Also the cases I formed ended up slightly shorter than the minimum length. I suspect a few firings and they would grow, but I haven't made any into live rounds and tested that theory.

03 February 2020, 22:30

Tyke

quote:
Originally posted by hogfarmer:
As I had some virgin Starline 32-20 brass around, I took my RCBS dies and formed a few 25-20 cases. They measured .346 at the base. As I used dial calipers, probably not overly accurate but close enough. I made up some dummy rounds using 86 grain jacketed bullets and they fed and chambered perfectly in my Winchester model 92.

What dies did you use?

Obviously this is only one example, so take it for what it's worth. Also the cases I formed ended up slightly shorter than the minimum length. I suspect a few firings and they would grow, but I haven't made any into live rounds and tested that theory.