Rebating a WSSM head to 308 for 35 caliber

M

mgreenwell

Guest
I have been working on a project to build a 35 caliber rifle cartridge.
The case is made from formed 243 WSSM, necked-up to 35 caliber.

35 caliber is the legal size for hunting deer with rifle in Indiana.
The WSSM case is short and fat, allowing it to meet the max cartridge length.

Does anyone have experience rebating the larger WSM cases down to 308 size. I have read some posts here regarding the 308 down to PPC, PPC down to 223 and so on, however nothing about a WSM down to 308.

My concern is there is a lot of brass to be removed to clear the extraction claw (Ruger M77 Target action). Will the brass start to grow back into the void left to clear for the claw? Or worse, will it be too thin and rupture.

The WSSMs have a rep for difficult extraction due to bolt thrust, with the reduced bolt head size maybe this can be reduced, I know the force has to go somewhere, wonder if it will push back the web into the extractor groove taper.

The other alternative is to open up the bolt face, I was hoping I could avoid that.


I have sectioned a few cases and it looks like there should be plenty of brass in the web, thought I would seek knowledge from the forum.
 
watch out you guys...there is a 35ppc/wssm comming to a score match near you!!!


mike in co
 
Make it easy on yourself, use a Savage action. They have the least bolt recess.

Gears grinding in head = heck, if you use a Savage you can get the correct bolt head and not waste time rebating rims.

Plan C = 358 Win.
 
mgreenwell said:
The WSSMs have a rep for difficult extraction due to bolt thrust, with the reduced bolt head size maybe this can be reduced, I know the force has to go somewhere, wonder if it will push back the web into the extractor groove taper.
Click to expand...
The bolt thrust isn't a function of *only* the case head -- in short, it will be the same whether or not you reduce the case head itself, as long as the case proper stays what, .540? As for the project itself, seems like a lot of work & expense -- reamer, dies, etc. for very little gain. Not that I haven't been known to do the same sort of thing . . .
 
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Given the parameters of Indiana's DNR regarding the specs for "handgun" cartridges in rifles, Mike is maxing out case capacity that meets the specs. Any case over 1.625" is not allowed nor any bullet OD less than .358.
 
I will let you guys in on a secret:

You can buy a heck of a lot of meat for what it will cost to make this rifle.

Plan C: 35BR
 
CRB

I did just that when I was shooting a 270/6.5 WSM. Made up a carbide form tool to rebate the rims.
It's just taking space in the tool box. Yours to borrow if you like.

Alan

I did find with loads on the warm side ( and over vel for best grouping) that the rebated ones lost pockets a single grain sooner than the originals.
 
Thanks to all who replied to the thread.

I made some test cases and fired at the range with good results.
With the WSSM being a really fat case, I had to open up some champhers of my primer tooling. Also had to dress some champher on the bolt nose.

Fire forming went well with a starting (fire-forming) load of 44.0 gr 4064. Extraction so far is not a problem. The bolt opens easily, even after the 2nd fire forming.

no signs of pressure problems or bolt thrust yet. I have not worked-up to final loads but the initial results were positive.

As far as extra expense to build the rifle I have talleyed the following so far:

243 WSSM Winchester brass 100 each (35.00)
Adams & Bennett 35 caliber 1-14 twist (80.00)
Nosler Accubond 225 gr box of 100 (35.00)
Sizing die from RCBS needs modified for 35 cal neck (27.00)
Chambering, die building, brass modifications (did it myself)
Used a Ruger Target action that had been on the back shelf (500.00)
Reamer and headspace gage borrowed from a buddy (owe him a big favor)

The look on the Game Warden's face when he asks to see the legal cartridge that I am using to kill dear in Indiana at 200 yards, and I pull out the
35 caliber IDC WSSM with rebated 308 head:

PRICELESS


BTW: Mark, thanks for the use of the reamer and headspace gage, I owe you one.
 
358 wssm-in

I start with a Rem 700 SPS in 270 or 300 WSM and rebarrel to 358 WSSM-IN (1.800). Cases are formed from 325 WSM brass. With Douglas 1&14 twist barrels we get about 3000 fps with Hornady 180's. Just a tad overkill for IN deer but thats the law.
 
I looked up the specs for what they allow for a rifle cartridge in Indiana. Don't blame you at all for building a .35 on a WSSM case. Not sure I understand their reasoning behind the case size and caliber restrictions, but am pretty sure they won't like your cartridge since what they are showing as legal are pistol cartridges shot in rifles. I'd probably do the same thing if I lived in Indiana. Good luck and good hunting with it.
 
My guess (and it's only a guess) is that the stricture is due to population density? Out here we have "shotgun only" areas around the towns because the slugs (and pistol chamberings) are more easily contained.
 
IN deer rifle regs

Al, right or wrong, I have always been told it is because the top half of the state is so flat.
 
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