cheytac based wildcats

[jon12]

What kind of long range hunting wildcats have been made, or could be made using this case, as is or maybe even shortening it. How does this case compare to other big commercail cases like lazzeroni or RUM or 378 weatherby based stuff? Does anyone know where to find specs or case drawing of this case like what is in a reloading manual? Ive heard of some really high velocities with this case with maybe .338, but could it be used to get 4000 fps plus in even small bullets like 30 cal or 7mm, or would it be so overbore that it would be really inefficient and suck? Does anybody have any velocities, data, or accuracy info on cheytac based wildcats?

Just an interesting topic to me. Thanks for any info.

 

[sscoyote]

Jon-- Bruce Artus of Pueblo West, CO is working with the 408-- necking it to various diameters. He just built one for a guy in .378 configuration, using a Granite Mtn. action. He's in the book.

 

[Brent]

I have a hunch that once you neck it down to about .338, the 50 BMG powders will be about right for that combo, I think they're a bit too slow for the 408 caliber from what I remember though.

The 408 was based on the 505 Gibbs case, so anything .510 on down should work just fine. I think it would be sweet to set one up for .510 and throat it for the 750gr AMAX.

I've heard the brass is very good, no problems with it, 408 bullets are a different story.

I've got the specs from a 408 CT case I measured if you want them.

The 338 Lapua case is the strongest of them all, thicker than the 408 in every way. In my opinion, they should have modeled the 408 case design after the 338 Lapua.

 

[ewallace]

I would take a close look at a 338 with 300g SMK with the 408 case. I think a 300 rum case would be a little over bore for a 7mm 112g of H2O an imp 338/408 will hold 170g H2O and use in the neighborhood of 130+g of powder with 300g bullets

 

[Randy in Va]

EDM Arms is delivering a 338/505 Skeletonized rifle now.

 

[JayIdaho]

Bumping the C-T up to .50 cal is the best idea that I've seen offered for the big case. That could be fun and worthwhile.
Somebody should run the numbers through the Quikload program.

 

[jon12]

brent i would be interested in seeing those specs.

 

[Ron Johnson]

Brent,
I wound also be interested in the spec on the 408 case. With a case cap. of 170 grains of water I wound think about 135 - 145 grains of WC872 or T-5070 with the 300 gr Sierra in a 36-40" barrel will get out about 3500 or so? It sounds good but what actions can be used? Thanks for your help!!

 

[Brent]

408 CheyTac brass was measured as follows:

Neck thickness - .014
Top of shoulder - .015
Near base - .050
OD below shoulder - .600
OD at base - .633
Case OAL - 3.330
Length - base to top of shoulder - 2.675
Length - base to bottom of shoulder - 2.450
Case web thickness - .240

Water capacity - 167.5gr (Virgin 408 CT brass)

 

[Brent]

Randy, Dave...

Have I got that case OAL right? That puts it at .655 for neck length.

I assume Bruce Baer blew his 338/408 CT shoulder forward because it looks more like a .300 neck length on his. He's easily into the 175gr water capacity range if so.

Eric,
Any way you can measure up one of his 338/408 CT cases to compare?

I think the reamer I'd go with would be .615 OD at the shoulder, a .400 neck length and let the shoulder lengths fall where they would with a 35 or 40 degree angle. A reamer with a .365 neck would be about right for a loaded round of .363...