Case Forming a False Neck - How Big is Too Big?

[5shot]

Making some 35 Whelen AI Case from some 30-06 Brass I have laying around. I necked them up to 75 first, so that I could get a nice fit in the chamber. It didn't seem like I was getting much of a shoulder, so I tried a 0.416 expander. That worked great, but I am wondering if I have too much of a good thing. I did anneal the cases first, and everything looks good.

Should I just stick to the 0.375 expander?

Thanks

 

[truck driver]

The ones I formed from 30-06 cases I just ran them threw a 35Whelen sizing die and then fire formed them in my AI chamber. I do get a crush fit with factory 35Whelen so I have no problems fire forming.

 

[5shot]

Mine is a tad too long to use factory stuff. I don't feel any crush when closing the bolt, which isn't a big deal if it addressed properly.

 

[Dwh7271]

Does the neck w the shoulder chamber? That will determine that for you.
For 264s, I run them through a 284 expander, then into the correct neck die and resize the top 1/2 to 2/3. I leave about 1/3 false shoulder.
It would seem to me like 416 to 358 is a pretty big shoulder although in you rifle it may work.
FWIW I'd use the 375 if it provides the tight fit on the false shoulder.

 

[5shot]

Thanks Dwh. Everything chambers, since I run it through the 35 Whelen AI die afterwards. I'll try backing the die out a smidge and use the 375 expander again.

 

[Dwh7271]

I know you probably know this but only size the top one half to two thirds of the neck. Leave the bottom part of the neck oversized. Should be a little bit of a squeeze when you close it. If you fully resize in the die you can take the false shoulder out by accident. Heck, if it will close with the bottom of the neck sized to 416 you'd be fine to keep using that also. Anyhow, that little tightness or squeeze is what holds it in place when you fire it forming the new cartridge in the chamber.

 

[5shot]

I have been putting a shim under the die so that it isn't fully resized, but to my eye it looked like the 375 wasn't leaving me with much to work with. Probably just paranoid. I have it set up so that bolt closes hard on the case, so I should get a good forming.

 

[SJB358]

I know you probably know this but only size the top one half to two thirds of the neck. Leave the bottom part of the neck oversized. Should be a little bit of a squeeze when you close it. If you fully resize in the die you can take the false shoulder out by accident. Heck, if it will close with the bottom of the neck sized to 416 you'd be fine to keep using that also. Anyhow, that little tightness or squeeze is what holds it in place when you fire it forming the new cartridge in the chamber.

Yup, I'd run it, if it chambers I wouldn't see any problem with it at all. Take some pictures if you get a chance. I would like to see the process.

 

[5shot]

I chucked up the 416 expander in my drill and used a stone to turn it down to about 0.385". I definitely get a bit better fit than I did with the 375 button, but I might have been able to achieve the same result by backing the die out a bit more. When it was at 416 it seemed like I was tempting fate, so I decided to make it a bit more svelte. I do like the custom button better though, because the 426 sizing button is tapered and I can open up the 30-06 case in one step (I mounted it in an extra die body I had). I then run it through the 35 Whelen AI Die and they are ready to shoot. I backed the sizing die off the shell holder until I had nice, firm pressure to close the bolt handle. Shouldn't have any issues.

 

[SJB358]

Looks pretty cool. That seems like a great method.

 

[truck driver]

Boy I'm glad I didn't have to go threw all that to form my 35Whelen AI cases.
They do look good.
I may have snagged a 280 or 270 case to try just to see if it would fit and give some resistance or crush fit since they are longer than the parent 30-06.

 

[5shot]

It's a bit of work, but not too bad. On the plus side, I am ready to form for the 375 Whelen!

 

[Dwh7271]

Aw geez. A 375 Whelen?
It's bad enough with the 35 Whelen around here, now a 375??? :lol: :lol:
Dont know why all the fuss when everyone knows the 338 Whelen is by far the superior cartridge. :lol: :lol: :lol:

 

[jimbires]

I've never done this and I have a question .

I think the false shoulder is used to hold the brass back against the bolt . would just necking up the brass to the correct size ,and loading a bullet long , so it's jammed into the rifling work ? wouldn't this accomplish the same as a false shoulder ? or doesn't the brass blow out correctly ? thanks Jim

 

[Dwh7271]

You are correct, jamming also works.
The drawbacks to jamming are potential pressure spikes, inadequate neck tension allowing the bullet to set back (defeating the jamming purpose).
The false shoulder helps hold the case firmly against the bolt hopefully allowing full brass formation.

 

[jimbires]

You are correct, jamming also works.
The drawbacks to jamming are potential pressure spikes, inadequate neck tension allowing the bullet to set back (defeating the jamming purpose).
The false shoulder helps hold the case firmly against the bolt hopefully allowing full brass formation.

Thanks Dewey .

 

[Dwh7271]

Sure Jim, anytime.

Couldn't get a rise out of any of the Whelen guys could I. :grin:

 

[jimbires]

Sure Jim, anytime.

Couldn't get a rise out of any of the Whelen guys could I. :grin:

NOPE !!

 

[truck driver]

Sure Jim, anytime.

Couldn't get a rise out of any of the Whelen guys could I. :grin:

NOPE !!

:lol: :lol: :lol: :lol: :lol: :lol: :mrgreen: