6MM Remington (Wildcat?)

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Harold_V
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6MM Remington (Wildcat?)

Post by Harold_V » Sun Jul 01, 2012 2:08 am

pacrat,

Ok, did some snooping and found a box with one fired cartridge and several loaded cartridges. None are factory 6MM. The cases have been formed from either 30-06 brass or 8MM Mauser brass.

I checked the specs on reamers, but the page that displays the 6MM Remington also displays the 244 Remington. As a result, the drawings are reduced in size and very difficult to read. I'm not convinced I could read them properly. I also looked at the 6MM Ackley Improved. It's definitely not that cartridge.

Here's a picture of the brass:
6MM Rem cartridge.JPG
I measured the fired case, which very closely resembles the loaded cartridge. Shoulder to the base is 1.765", with a .430" diameter at the shoulder. Angle appears to be correct, although I never bothered to check with a protractor or my comparator. The shoulder angle has never appeared to be an issue and appears to be identical to the angle created by the dies (RCBS 6MM Remington). I measured the diameter of the case at the base (head). Where the brass thins (above the groove) it measures .472". Unfired cases are somewhat smaller in diameter, anywhere from two to five thou. I attribute the variations to the mixed brass used to form the cases.

I could not determine the proper length to the shoulder from the link provided, and I was not successful in locating any of my reloading books. The tag included with the loaded cartridges is dated October 22, 1976, which is likely the last time I paid any attention to the cartridge length. Once I had the issue resolved, I never worried about it again.

Don't know if you'd be interested in a picture of the rifle, but I took one while I was taking the picture of the cartridges.
6MM Rem.JPG
I'm not well versed on actions. The one used for the 6MM closely resembles the FN used when my 458 Winchester was built (also by Ackley). It is marked on the left side Mark X as well as Interarms, Alexandria Virginia. Don't know if that's useful to you, or not.

Harold
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pacrat
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Re: 6MM Remington (Wildcat?)

Post by pacrat » Sun Jul 01, 2012 3:54 am

:shock: :o :roll:

OK, according to all my references compared to your chamber. What comes closest as far as known wildcats is the {6mm Arch}. But even it has differences of shoulder dia. and maybe shoulder angle. Body lenght dim. is same at 1.765". But shoulder dia. is .448" as opposed to your .430" which is a standard 6mm Rem. shoulder dia. So it is undoubtedly a previously unknown wildcat with a lineage of unwed parents in its family tree. :wink:

How about we call yours {Harolds 6mm Weird Duck} ??? :lol:

Sorry about 4-D's link.....The 6mm Rem. and the 244 Rem. are [exactly] the same case. If you scroll down to the next line of reamers and look on the left side there is a link/drawing of the 6mm Rem/.244 Rem which is full size and clear. Instead of 2 smaller drawings and unclear. The only difference in designation is a change in the twist rate of barrels. The 6mm being faster spinning to stabilize 100+ grain bullets. Rem. made the 244 first but rate was to slow and it wouldn't stabilize bullets over 85 grs. The 243 Win. stomped it in the marketplace. So Rem. changed the twist and the name but never caught up with Winchesters sales. Even though the 6mm is a ballistically superior cartridge.

According to my feeble math skills you could run a 6mm Ackley Improved reamer into your chamber and clean it out to AI specs. Then just add AI to the cartridge designation on the barrel. This could be done with a hand driven reamer and a {go gage}. That way any time in the future should the rifle pass hands without you standing there telling new owner of chamber variations it will be clear it is a wildcat and which one. Any knowledgable shooter, gun tinkerer, or smith immediately recognizes what AI after cartridge stands for. But don't do so until you get an accurate dim. from base to shoulder/neck juncture. That dim. could be the bug in the soup.

Other option to make it a legitimate 6mm Rem chamber would be pull barrel and face of breech and shoulder required thousandths to reset headspace to standard SAAMI spec. Not to tough to do with a Mauser. But option 1 would be easier because barrel would stay on reciever during reaming.

Interarms Mark X's are built on recievers made in Spain by Santa Barbara. They are as you noted a m98 Mauser same as your FN.

I brainfarted my initial thinking on this dilema because it should have been obvious to me that it could not be an AI chamber or you couldn't neck size cases in a standard FL 6mm die. Shoulder of AI is .026" larger in dia and would have bound up real tight in a standard die.

I'm truly amazed that a screwed up chamber mess like this came out of Parker Ackleys shop. Just goes to show that anyone can/does makes mistakes.

Thanx for the opportunity to scratch my head some and dig out the dusty old wildcat cartridge reference books.

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GeorgeGaskill
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Re: 6MM Remington (Wildcat?)

Post by GeorgeGaskill » Mon Jul 02, 2012 4:46 pm

SAAMI has published a new set of cartridge/chamber drawings including many of the new short fat ones dated 2009. Voluntary
Guidelines For Ammunition and Firearms CARTRIDGES & CHAMBERS
. Select the rifle cartridges (Section III) list, then select 6mm Remington for the actual drawings.

Harold_V
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Re: 6MM Remington (Wildcat?)

Post by Harold_V » Mon Jul 02, 2012 11:35 pm

Thanks, George.
Couldn't get the link to work, but I roamed the net and found a drawing that indicates base to shoulder dimension for the 6mm case should be 1.725". No question about it, mine isn't proper, so I have a true wildcat. Shoots fine with the slightly longer case, so I'm satisfied with things as they are.

Harold
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Re: 6MM Remington (Wildcat?)

Post by websterz » Thu Jul 05, 2012 4:59 pm

Image

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GeorgeGaskill
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Re: 6MM Remington (Wildcat?)

Post by GeorgeGaskill » Fri Jul 06, 2012 2:51 pm


Harold_V
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Re: 6MM Remington (Wildcat?)

Post by Harold_V » Fri Jul 06, 2012 3:10 pm

GeorgeGaskill wrote:Maybe this will work:

http://www.saami.org/PubResources/CC_Dr ... ington.pdf
No joy. I can enter the saami.org site, but if I click on the button for cartridges, it ceases to cooperate. Not really a problem at this point, as there's no question the rifle in question has a headspace problem, which has been addressed by forming longer cases. It would be interesting to know how it managed to leave the shop that way, though. Guess I'll never know, considering Ackley died about 20 years ago.

Harold
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Re: 6MM Remington (Wildcat?)

Post by hammermill » Fri Jul 06, 2012 5:11 pm

well the extra legenth allows for a schosh more powder. maybe a few more 100 feet per second. such is the fun of wildcats.

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Re: 6MM Remington (Wildcat?)

Post by Downwindtracker2 » Sat Sep 27, 2014 6:27 pm

I think you might have Parker Hale mixed up with Interarms, on that Spanish connection. The later Interarms were Zastava made.
A man of foolish pursuits, '91 BusyBee DF1224g lathe,'01 Advance RF-45 mill/drill,'68 Delta Toolmaker surface grinder,Miller250 mig,'83 8" Baldor grinder, plus sawdustmakers

Steve S
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Re: 6MM Remington (Wildcat?)

Post by Steve S » Mon Oct 13, 2014 7:41 pm

Harold , did you ever get that figured out ?
You could cast the chamber with "carosafe"

What exactly were you trying to figure out ?
I have in my possession the holy grail of wild cat books .
"Designing and forming custom cartridges for rifles and handguns" by Ken Howell

Let me know if I can help .
Steve S

Harold_V
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Re: 6MM Remington (Wildcat?)

Post by Harold_V » Tue Oct 14, 2014 1:21 am

Steve S wrote:Harold , did you ever get that figured out ?
You could cast the chamber with "carosafe"
I'm pretty sure I understand the problem, Steve. What I ended up with was a custom built rifle that had excessive headspace. Why, I do not know. It was discovered only upon my firing the rifle for the first time. Three shots were fired, with two of the three cases failing. There were no injuries.

I solved the problem of the one of a kind wildcat by simply forming cases that were a little longer than spec for the 6MM. The only issue is that the rifle is marked as a 6MM Remington cartridge, but standared 6MM ammo is unsafe to fire in the rifle because of the headspace. The custom cases work perfectly well, and are sized and loaded simply by a simple adjustment of the loading dies. From my vantage point, there's nothing amiss. From the vantage point of the range officer, where I first fired the rifle, it was a dangerous weapon because it had excessive headspace. This dude had no understanding of the term, and couldn't come to terms with the idea that all one must do is make a cartridge that fits the chamber, regardless of deviations from normal, and there is no headspace problem. A prolonged discussion with him on this topic proved to be fruitless.

Some folks need to learn that there's a time to talk, and a time to listen. He was one of them.

This, of course, was MANY years ago---early 70's.

Harold
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Re: 6MM Remington (Wildcat?)

Post by GeorgeGaskill » Mon Oct 20, 2014 5:19 pm

You might consider adding the word SPECIAL following or underneath the 6MM REMINGTON marking to at least get the attention of subsequent owners that the chambering is not the factory 6MM Rem.

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