338 whisper, 338 hush, 338 thumper?

[andym79]

Hi guys, perhaps I am not looking hard enough.

I am trying to find case drawings to see the difference between the 338 whisper (2 very different ones?), 338 hush (not sure) and 338 thumper (223 cut off at the shoulder?).

Can anyone tell me about the differences and pros and cons o each.

I am looking at build a 338 wildcat to shot big slugs slow, but can't get enough data on any of these like you can for commercial cartridges.

Thanks

Andy

[Gwion]

Try googling reamer and die makers. Their websites mostly have lists with links to cartridge specs.

[andym79]

Maybe I am looking at the wrong websites! But no case drawings on ptg clymer Manson or ch4d!

[Gamerancher]

"Whispers" are a proprietary range of cartridges designed by J.D Jones of SSK Industries. His aim was to design a series of cartridges that would deliver long range accuracy and energy at sub-sonic velocities. They are primarily for use in suppressed firearms, although very good results at super-sonic velocities are also achieved.. All chamberings up to the .300 Whisper use the .221 Fireball case. Various parent cases are used from then on up to a couple of .50 cal Whispers.
.338 is the largest caliber possible with a .223 case and then it gives a straight walled case that has to head-space off the case mouth. The .338/.223 Straight was tried in 1972 in two versions, one by necking up the full case and the other by cutting it off at the shoulder. For your plans to build on a Martini action, you would be better off using .222 Rimmed which would head-space on the rim. The J.D Jones .338 "Whisper" uses 7mmBR case.
Buy the latest copy of "Cartridges of the World".

[andym79]

Hi, thanks for the reply, the plan was never really to try and use a 221 or 223 case in the martini. Rather my line of thought has been more along the path of using either 222r or 5.6x50r as the parent case for a .284, .308, .312, .323 or .338 neck up version, similar to whispers but not the same.

I think cutting off the 222r or 5.6x50r at the shoulder and turning it into a straight wall would be the go if I decide I really want to go this route!

In some ways I am more tempted to use the 5.6x50r as the parent case than the 222r!

I know almost nothing about the finer details of cutting a chamber; but could a straight walled (or almost) .338" case about the length of a 222r be achieved by cutting a 221 chamber and then extending it with a neck and throat reamer thus making a chamber that allows for a case tapering from .377" at the base to .361" at the neck and being 1.65" long?

If this option is possible then I would probably fireform 222r brass or cut shorter and fireform 5.6x50r brass.

The other option going through my head to create such a chamber would be to cut a 357mag chamber and finish it of with a neck reamer up to 1.65", again the intention would to fireform either 222r or 5.6x50r brass. The thing that concerns me about this option more than the first, is can a gunsmith cut a nice tapered shoulder/neck as the 357 mag chamber would be a tiny bit oversized for a case with OD of .361-.370" at the mouth.

Are either of those options realistic or is only the third option of a custom chamber a realistic one?

Remember, whilst I prefer the idea of a 338-222r/338-5.6x50r does anyone think that 28-32 cal may be easier to do the smithing work for?

[<<Genesis93>>]

OK Andy.....

I would normally say go hard or go home (so a 338 supermag) but you want something a bit different...a bit soft (nothing wrong with soft)..

so here it is;



the 338 proj in the 223Rem case (lower) looks a bit 'not right'....

The same projectile in the 308win case (upper), shortened to provide similar 308win neck/shoulder geometry but to the 223Rem COAL and with 338proj, still looks a bit... anemic (I wonder if it would make it out of the muzzle ) bit if it does the job for you

If this hasnt been done in this geometry, you can have the concept Andy, and we'll call it the 8.6Andy (Throw the popo off the scent without the 338 in the name...)

Note both 223 and 308 can be swapped for rimmed, 307win and 222R

[andym79]

The bottom one has been done its called the 338 whisper #2 and 221 rem fireball opened upto 338 the third along,

DSC00703.jpg (41.57 KiB) Viewed 5518 times

there is also a 338 whisper #1 a 7mm br necked up to 338. I am only interested in the 338 whisper #2. However because I want something similar in a rimmed version I doubt a standard reamer is available (probably a custom go).



Could a smith cut a 222R and open it up with a neckreamer or does a 222r reamer need a 224 calibre barrel for its pilot?

[SillyWetTas]

Another option would be to get the chamber cut short with a 300 whisper reamer so the chamber length is the same length as a 357 magnum case . Shorten 300 whisper reloading dies to suit your chamber. Then you would have the neck length the same as the whisper but a slightly shorter case . I would think it would do anything a subsonic whisper load would do.
Marcus

[Old Fart]

God my eyes, who decided the case diagram needed to be fluro red and purple

[<<Genesis93>>]

Hows about Davie Shoebridge approved then?