Diameter bullet you could put into a WSM case and still get it to head space properly? I'm in a current discussion on this and I was thinking a guy could probably get close to a .458 diameter with the fatter case of the WSM. I got to hold Snellstrom's .411 PDK dummy cartridge he got from ramrod340, and that has a pretty small shoulder. Just wondering if you need a given amount of shoulder to head space?

If you're using a CRF (M98 Mauser style extractor) then you don't need a shoulder - a proven by Michael458 with his 50 B&M cartridge (uses a .500" diameter bullet) in a M70 Winchester CRF WSM action. If you're using a pushfeed action - think M700 Remington style extractor then yes you nheed a shoulder. The largest diameter bullet that you could use with a WSM dimension case and still have a shoulder is .500" diameter bullet. Michael458 has a 500 MDM which has a small shoulder using the .500" diameter bullet - this cartridge uses a RUM case cut to 2.8" length. As an FYI - the WSM and RUM cases are close to twins at the rim and case body base dimensions.

Jim,

Straight cases like the 50 B&M can headspace on the mouth of the case just like a 45 ACP. I think a .510 has been done on the WSM case and it headspaces on the mouth of the case. The Rum case is a little smaller in Dia. so .500 is max for it.

Sam

The rifle is already a .300 WSM M70 so I it is a CRF rifle. He is thinking of making it a .450 Marlin. I told him that I'd just neck it up to .458 and be done. He still thinks the .450 Marlin is a better idea, I still think my idea is simpler job.

quote:

I got to hold Snellstrom's .411 PDK dummy cartridge he got from ramrod340, and that has a pretty small shoulder.

That shoulder is more than the belt on a belted magnum. .013" per side for a total of .026 compared to a normal .02 total for a belted magnum.

That would be the 400PDK

Hey Sam,
LOL…and I believe that Michael would insist that the 45acp headspaces off the extractor not the case mouth! And I believe that’s what led him to do the 50 B&M to headspace off the extractor. But I do agree that the cartridge could be designed to headspace off the case mouth.

taylorce1,
If I may make a suggestion, look at having your M70 WSM rebarreled to .458 B&M…the .458 B&M performance will match and likely slightly exceed the performance of the .458 WinMag but in a cartridge that easily fits within the WSM magazine…or you can load down to the 45/70 and .450 Marlin performance level. Plus proper headstamped brass is available from Quality Cartridge. Here’s a link to the B&M website: http://www.b-mriflesandcartridges.com/default.html

In theory most cases will give you the same or more case mouth rim than a belt. As you crimp that would go away.

quote:

Originally posted by ramrod340:

quote:

I got to hold Snellstrom's .411 PDK dummy cartridge he got from ramrod340, and that has a pretty small shoulder.

That shoulder is more than the belt on a belted magnum. .013" per side for a total of .026 compared to a normal .02 total for a belted magnum.

That would be the 400PDK

Thanks for the correction, I just knew it used a .411 bullet. Very cool cartridge BTW, so how much further forward is your shoulder vs. the Hawk?

ramrod340,

simple alternative to crimping the case mouth. Just apply a taper crimp.

I built a 510 Wells Express on an Enfield, minus the irritating belt. 510 KX/510Rigby.

Thanks,

Based on the numbers Fred gave me on the Hawk my shoulder is .131" forward my shoulder dia is .46 which is less body taper. That give a maginal capacity gain. Big difference is the case length. The Hawk is 2.44" mine is 2.65". In theory you could load both to the same OAL and I would have a couple grs on him. However if you seat into the cannelure I have a significant gain. At 2.65" a 400gr Hornady seated in the cannelure is 3.24"

If you go to his site in the 411 Hawk he has a lot of 300gr and 350gr data with 26 and 27" barrels. I get a nice and easy 2250 with a 24" and 2350 if I push it.

QL doesn't have the Hawk in it however they have the Brown Whelen which is close. In the cannelure the BW is 3.15" and 52.18gr of net capacity. At 3.34" the BW has 58.55gr of capacity. At 3.34" the 400PDK has 64.7grs of net. That gives me either 105% or 24% more capacity than the BW and probably the hawk.

quote:

simple alternative to crimping the case mouth. Just apply a taper crimp

Never used a taper crimp other than handgun. Even if you use a taper into a cannelure wouldn't you loose the edge to headspace against?

Here is a close up of the shoulder on a .375 Ultra Magnum necked up to .458 ( 450 Ultra Magnum )

450 Ultra Left, 500 Jeffery right.

Taylor,

458 is plenty doable, and has been done in a few different variations. The basic neck up I believe, is the 458 Alpine from Australia. Seeing as your friend has the M70 WSM, he really should do one of the B&M's. Maybe send him a link to Michael's webpage? The extra length in the magazine is what spawned these cartridges, not the other way around. They are made from cut down RUM brass and are actually a bit longer then WSM brass.

Although, your friend DOES have a point about the 450 Marlin being a good choice (notice I didn't say better lol) because its a factory round. But, factory loads, and reloading data for them, is going to be on the weaker side. If he hand loads, especially with the extra length in the magazine (3.1") he could easily seat bullets farther out, and use heavier bullets then the Marlin was designed for.

But then again, if he handloads...there is no reason NOT to do a B&M.

Personally, I'd chose 475...but thats just me. Just as you could plink with cheap 458 bullets in the B&M, you could plink/hunt with cheaper bullets made for the 480 Ruger instead of always using bullets intended for the 470 Nitro.

.510 is the largest .. though, in theory, you COULD do a .530 bullet on it .. with nothing to headspace on...

however, the best you can do, at 3.35" oal, are the 416, 458, and 470 AR . screw in a new barrel to a "mag" and away you go...

myself, i only do over .475 on a rigby casehead

Jeffe weren't you using some .474 pistol bullets in the 470? Speer Gold Dots maybe? I'm rather interested in that gun, might need to chat with you about that.