.400 Whelen

[Rum River]

For years have toyed with the idea of building one of these, "just because". Was reading some info last night, regarding the headspace issues some have had. (There have been occurrences where there's little shoulder present there wasn't enough resistance to the firing pin blow to fire the primer.)

I learned that while the current shoulder dimension is .441", the original dimension used by Col. Whelen was actually .458".

Is anybody familiar with the .400 Whelen development to confirm this? Has anyone here ever loaded for one?

[Lone Star]

If you have not, go here:
http://www.z-hat.com/smashing_the_headspace_myth.htm

I know the author and he is a respected straight shooter...I trust his reaserch completely.  There is a lot of BS posted on the Internet on this topic, one "author" I read stated that the .400 was the only cartridge ever developed by Whelen!  Over the past 20 years I have read two independent loading articles on the .400, and neither writer had headspace issues - one was chambered in a M700 and no hook extractor to hold the case back to the breech.  I do not remember the chambering dimensions.

All this said, a better choice may be a .400/.240 Weatherby.  The Weatherby headspaces off the belt so no matter what the issue with the shoulder, the belt is the ultimate stop.  I knew two hunters in Alaska who built .416/.240s and they worked very well.  Since you have to buy custom dies anyway, the only difference would be the more expensive Weatherby brass.  since this cartridge would be used on large, possibly dangerous game, why screw around with feeding reliability?

.

[PaulS]

The only belted magnums that actually headspace off the belt are the H & H magnums. All other magnums use the shoulder to headspace. There are many articles on this issue in reloading manuals. Using the belt to headspace the cartridges is why they fail so fast to incipient head separation. If belted magnums are headspaced on the shoulder they last many more firings than the three or four that thit takes for them to fail otherwise.
The bad part of using a wildcat (and I use a few) is the inconsistent chamber dimensions. If you use that inconsistancy to your advantage you can provide a larger shoulder to headspace on. short of that using a minimum chamber dimension may be the only other way to combat a small shoulder on a cartridge.