Wildcatters , I found a neat round , what is it

I found a shell casing this morning ata pit that I shoot at , it looked sort of familiar untill I picked it up. I took it home and started measuring it out with the calipers and here is what I came out with.

It appears to be the same dementions as the
RSUM but the shoulder has been pushed back
from the standard 1.538 to 1.450 , and it looks to have a 35deg shoulder. The case neck is .295 on the outside which leads me to think its some sort of 6.5 Wildcat.
The parent case is a 300WSM by Norma.

Any of you cartridge makers out their ever heard of such an animal ? It seems to me that the case capacity would be close to what the 6.5x284 is maybe a little bit more.

[winmagman]

JDJones There have been a few posts on the 6.5x300WSM on this board. I'm not sure by who, but there are guys out there playing with that combo.
Chris

I have seen a 6.5x300WSM and that is what I thought it was but this is a little sjorter and thinner like the 300RSUM compaired to the 300WSM.
I figure that somebody is just trying to make a little more effecet case ? or maybe just something they can call their own ?

[DANTEC]

there is long cartridge base on RSUM by WHKELLEY this shooter is on benchrest.com forum , his idea is to get better design than regular 6.5/284 and get a better water capacity matching with bullet weight to increase barrel life

6.5/300 WSM Is far bigger and stay with a short neck wich is not amazing ting for barrellife , 6.5/300 WSM with 0.35 neck lenght can be perhaps a better design with less powder and same velocity , most velocity record on this board are in the 3100 fps wich is low for a big case in 6.5 , with a 264 WIN volume ( 6.5/300 Yuma ) I get easy 3300 fps in a 30 inch barrel with very good accuracy .

good shooting

DAN TEC

[scottl0000@hotmail.com]

LOL, one of the folks replying to an earlier post I made linked me to this thread... it seems either great minds think alike, or (more likely that I've recreated a very old wheel. may case is only slightly longer in the body but has the exactly same neck length as the one mentioned below, .350". That being said I was going to add a link to a post where a drawing is attached that MikeCR was nice enough to put together for me. It also lists the comparative drawings and case capacities for the .260 Remington, the .270 WSM, the 6.5x.284 and the 6.5 WSSM (with their capacities). Hopefully others will find this information useful.


The drawing is attached to one of my replies over at 6BR at Need info quickly on 6.5 options -help! -

Thanks,
Scott

Originally Posted by DANTEC

there is long cartridge base on RSUM by WHKELLEY this shooter is on benchrest.com forum , his idea is to get better design than regular 6.5/284 and get a better water capacity matching with bullet weight to increase barrel life

6.5/300 WSM Is far bigger and stay with a short neck wich is not amazing ting for barrellife , 6.5/300 WSM with 0.35 neck lenght can be perhaps a better design with less powder and same velocity , most velocity record on this board are in the 3100 fps wich is low for a big case in 6.5 , with a 264 WIN volume ( 6.5/300 Yuma ) I get easy 3300 fps in a 30 inch barrel with very good accuracy .

good shooting

DAN TEC