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Looking for info on a competition cartridge.

Hi all,
I was reading the 6mmbr.com Page about competition cartridges, specifically the section about score shooting cartridges (Hunter BR), and came across this picture (ive cropped it to assist) and wanted to find some more info on the cartridge in the center (to scratch my curiosity) labeled PI-II, not sure if theyre i's or 1's, but it's the short fat one that appears to be 30cal judging from the size of the projectile compared to 308w, (also in picture)

any links to some information would be greatly appreciated, if anybody knows anything about it would also be appreciated

Ps. If this post is in the wrong location sorry I'm new here.
 

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Hi all,
I was reading the 6mmbr.com Page about competition cartridges, specifically the section about score shooting cartridges (Hunter BR), and came across this picture (ive cropped it to assist) and wanted to find some more info on the cartridge in the center (to scratch my curiosity) labeled PI-II, not sure if theyre i's or 1's, but it's the short fat one that appears to be 30cal judging from the size of the projectile compared to 308w, (also in picture)

any links to some information would be greatly appreciated, if anybody knows anything about it would also be appreciated

Ps. If this post is in the wrong location sorry I'm new here.
what were the dates on the posts ???
 
Looks like an improved WSSM case necked to 30 caliber (maybe .338).
I've thought about that, I was thinking its too short to be a standard length wssm, could be shortened, but another thing I thought about was, it seems too thin (rim diameter) I'm looking for an image of 30wssm next a 308 to maybe compare that way (I don't have either on hand at the moment).
 
Case overall length appears to be very close to the body shoulder junction of the Aardvark cartridge, with some extra body diameter. maybe enough to be a wssm wildcat but It doesnt look that much larger than 308, and after viewing images of 243 wssm and 243win next to each other, the difference in case body diameter is quite large (image found on 243 wssm wikipedia page).
 
Definitely a "magnum" sized rim.
And looks larger in diameter than a shortened 284 Win case. (Of course the rim size would be the same as the other cartridges)
@Fuj would have pictures of his shortened 284 cartridges.

Something on a very shortened 375 Ruger case maybe.

Note.

Depending on the angle you look at them, the picture doesn't look that much different in comparison to my 25 WSSM alongside my 284 Win, 280 Rem, & 7mm-08AI.

I'm still leaning towards a wildcatted WSSM case.
 
Maybe
Definitely a "magnum" sized rim.
And looks larger in diameter than a shortened 284 Win case. (Of course the rim size would be the same as the other cartridges)
@Fuj would have pictures of his shortened 284 cartridges.

Something on a very shortened 375 Ruger case maybe.

Note.

Depending on the angle you look at them, the picture doesn't look that much different in comparison to my 25 WSSM alongside my 284 Win, 280 Rem, & 7mm-08AI.

I'm still leaning towards a wildcatted WSSM case.
Maybe, it could be based on something with a very odd rim size, or a larger magnum case, could it be a extremely short 404 Jeffreys wildcat? Not sure about the jeffries, but it's definitely larger than the 308 diam, what are some other rim sizes in relation to their popular caliber with said rim?
 
take with a grain of salt these numbers because they are guestimations based off an image

after doing some very rudimentary and most likely highly inaccurate measurements off my screen ( measuring the screen sizes, and finding the percentage difference between the 2 cases, then guessing as to what the rim size could be and comparing with a known cartridge (308 win in this case) the case im looking for was approx 15.221987 percent larger than the 308, and the WSSM case rim is 15.096774 precent larger than 308. that being said, there is a 100% chance of my measurements off my screen being innaccurate, but with it being so close, im willing to make the assumption that this is a shortened blown out 30 cal WSSM wildcat.
what i also did, is i measured the case length to try to estimate how much it was shortened by, using the same inaccurate method to get a rough percentage size difference between the two cases (the unknown PI-II) and WSSM, and from there found that percentage to be 65.784503 percent, which i can estimate to leave the PI_II with an overall case length of approx 1.1 inches (more specifically 1.0986012001 inches, but im rounding because this guestimation is already as inaccurate as set of calipers being used as a hammer)
 
Maybe

Maybe, it could be based on something with a very odd rim size, or a larger magnum case, could it be a extremely short 404 Jeffreys wildcat? Not sure about the jeffries, but it's definitely larger than the 308 diam, what are some other rim sizes in relation to their popular caliber with said rim?
The 404 Jeffery and iterations thereof (RUM, WSM, RSAUM, Dakota) have roughly a 0.532-0.535" rim diameter.
So same as the popular belted magnums, and the cartridges taken from the 375 Ruger.

The body OD is what is really different.
Cartridges based off the Jeffery with 0.540-0.545" typically.
Whereas cartridges based off the 375 Ruger are 0.532".

So the Jeffery based cartridges have a slightly rebated rim.

Whereas the AARDVARK is a rimmed case.
 
There is a member here on the site that has a large collection of all kinds of wildcat and standard cartridges. Maybe he will see your post and chime in. If you can find the name of the poster of the picture, it would be a great help.
 
There is a member here on the site that has a large collection of all kinds of wildcat and standard cartridges. Maybe he will see your post and chime in. If you can find the name of the poster of the picture, it would be a great help.
I assume the person who took the photo wrote the article but there is no credit associated with it
 
The 404 Jeffery and iterations thereof (RUM, WSM, RSAUM, Dakota) have roughly a 0.532-0.535" rim diameter.
So same as the popular belted magnums, and the cartridges taken from the 375 Ruger.

The body OD is what is really different.
Cartridges based off the Jeffery with 0.540-0.545" typically.
Whereas cartridges based off the 375 Ruger are 0.532".

So the Jeffery based cartridges have a slightly rebated rim.

Whereas the AARDVARK is a rimmed case.
Yeah I did some looking at the various rim diameters and some bootleg measuring and came to the conclusion its a 30 wssm shortened to 1.1 ish inches
 

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