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Offline woodsrunner

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re-chamber
« on: April 09, 2005, 05:13:22 AM »
Is there any reason I can't re-chamber a 7-08 to 7x57?
  I have a ton of 7x57 brass and dies for three other 7x57s to feed it with.
  Or, could trade a NIB .357Mag for a good 7x57.
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Offline quickdtoo

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re-chamber
« Reply #1 on: April 09, 2005, 05:54:02 AM »
From what I see of the 2 cartridge specs, it looks to me that you could...click on View cartridge drawing near the bottom of the page.

http://www.reloadbench.com/cartridges/757m.html

http://www.reloadbench.com/cartridges/708r.html
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Offline Mac11700

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re-chamber
« Reply #2 on: April 09, 2005, 09:29:08 AM »
I don't have the 2 cases to compare...but if the 7x57 is .454" wide at 1.560" from the base it should work...the 7x57 shows .431" at the shoulder junction of the case body...the 7-08 shows .454" at 1.560" and the 7x57 shows .431" at 1.730"...at least according to the Frank Barnes 10th edition cartridges of the world..

Anyone have the cases to measure?????This would be a pretty nice  conversion if it would work...


Mac
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Offline Lurch

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« Reply #3 on: April 09, 2005, 12:28:16 PM »
Looking at the dimensions in the cartridge drawings in Lee's Modern Reloading Second Edition it should work.
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Offline Fred M

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re-chamber
« Reply #4 on: April 09, 2005, 04:09:18 PM »
Good grief again. How do you guys figure to cleanup a .454"  chamber with a .430 reamer in a length of less than 2/10". What are you looking at? Mac with your mathematical prowess you disappoint me. I am the dummy that does not know math, and I don't need two empties to see that. You be just lucky to turn a 7-08 in to a 7x57AI. You only have two thou to work with, unless you find a reamer .with a .459 shoulder.
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Offline Mac11700

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« Reply #5 on: April 09, 2005, 07:14:43 PM »
Quote from: Fred M
Good grief again. How do you guys figure to cleanup a .454"  chamber with a .430 reamer in a length of less than 2/10". What are you looking at? Mac with your mathematical prowess you disappoint me. I am the dummy that does not know math, and I don't need two empties to see that. You be just lucky to turn a 7-08 in to a 7x57AI. You only have two thou to work with, unless you find a reamer .with a .459 shoulder.



Quote
Anyone have the cases to measure?????This would be a pretty nice conversionif it would work...



 
My My...getting a bit testy aren't we there  Fred......I never claimed to be a mathematical wizard Fred...not once...but you seem to have a penchant for holding grudges now...and I'm glad you have such phenomenal eyesite to be able to ascertain the difference in such minuet detail...awsome...certainly awsome...well since you can...enlighten us ...Oh' Master of the Gunworld.....what is the aforementioned case dimensions of which I spoke?
 
Mac
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Offline Fred M

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« Reply #6 on: April 09, 2005, 07:42:30 PM »
Mac
Just click on Quicks post, both drawings are nicely drawn up. on the two URL's. If you had looked at his post you would have seen it.
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Fred M.
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Offline Mac11700

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« Reply #7 on: April 10, 2005, 05:31:05 AM »
Fred:

I was just looking for the dimensions of where the shoulder of the 7-08 hits at  on the 7x57...when standing side by side...I have the case drawings...but no 7x57 case to take a physical measurement...

Mac
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Offline mitchell

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« Reply #8 on: April 10, 2005, 07:13:52 AM »
:eek:  wow hot crowd . i don't believe anybody on this site claims to be a mathematical genius. but being that most everyone on this site is older then me i'll cut some slack , go take a laxative have a nice sit down and come back in better moods.

but to get back to woodsrunner's question by looking at the links quick gave it should be possible i don't think there will be much room for error but thats just my opinion, i'm not a smith i'm just a 18 year old with a gun addiction . there is a few smiths that hang out a few forums down on the gunsmithing forum you may want to ask them to make sure.
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Offline Mac11700

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« Reply #9 on: April 10, 2005, 07:28:57 AM »
Mitchell:

No-one is "Hot"...we just have a difference of opinions...and sometimes it just seems that way...I know it would be a close call...but that's why I said " IF "...I don't have a 7x57 to measure it against...and figured Fred might have one laying around...and I don't need anything to help out my digestive track...the food I eat at the Hospital works great for that.....:eek:

Mac
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Offline while99

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« Reply #10 on: April 10, 2005, 07:31:04 AM »
Even if you have drawings of the two cartridges, you don't know the dimensions of the existing chamber.  Without doing a chamber cast you have no way of knowing if a 7 x 57 reamer will clean up the existing 7mm-08 chamber.  Get some Cerrosafe check metal from Brownells and do a proper cast.  Then you can determine if the 7x57 reamer will clean it up.
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Offline quickdtoo

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« Reply #11 on: April 10, 2005, 07:40:10 AM »
Quote from: while99
Even if you have drawings of the two cartridges, you don't know the dimensions of the existing chamber.  Without doing a chamber cast you have no way of knowing if a 7 x 57 reamer will clean up the existing 7mm-08 chamber.  Get some Cerrosafe check metal from Brownells and do a proper cast.  Then you can determine if the 7x57 reamer will clean it up.


That would work great if the 7-08 was in hand but if that isn't the case, it's still a matter of speculation, at least a case comparison would give the best guess without the purchase of the 7-08 with the intention of a possible rechamber. Personally, I would just rather buy the 7-08 and brass than to try the rechamber just to use up existing brass of the 7x57....If I really wanted a 7x57, I'd just wait until I found an actual 7x57 Handi.....but that's just my preference. :wink:
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Offline Mac11700

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« Reply #12 on: April 10, 2005, 07:41:13 AM »
Yep...that is true...and I do believe that's why Fred said to make it into a 7x57 AI...this would do just that...but I was just curious of what  the dimensions of the unfired 7x57 case was where the 7-08 case shoulder matches up to it...to see how close the 2 are there...

Mac
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Offline mt3030

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re-chamber
« Reply #13 on: April 10, 2005, 08:07:47 AM »
Suggestion: Call your gunsmith of choice and ask him to do this rechambering. If it is possible, he'll jump on the job. That is how he makes his living. Over the years I ask two, just to get a second opinion. Both stated that the 7x57 reamer would not clean up the 7mmx08 chamber, due to the 08's shoulder measurement. NOW, in a traditional bolt, the barrel can be set back a turn, then it's can do. But, make that call to your 'smith and get the word for yourself. And if you find out that I was misled, I'm sure you will share it with me. (Didn't we have this conversation just last week?)
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Offline while99

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« Reply #14 on: April 10, 2005, 08:13:23 AM »
Gentlemen,
IMHO, this is a no-go.  I just miked some once-fired W-W 7x57 cases that were range pickups.  I also miked a once-fired W-W 7mm-08 that was fired in my Model 70 compact chambered for that cartridge.
At a point 1.560 inches forward of the case head, the 7mm-08 case miked .456".  The 7x57 case, miked the same distance from the case head, miked only .435".  
A 7x57 Ackley Improved may indeed clean up the chamber but I don't have one of those from which to obtain the dimensions.  
If I wanted more performance than the 7mm-08, I'd buy a Handi in .280 Remington.  In fact, I just did.  The increased case capacity of the .280, coupled with the 26" barrel that H&R uses, ought to give velocity approaching the 7mm Remington magnum.
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Offline quickdtoo

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« Reply #15 on: April 10, 2005, 08:16:24 AM »
Now, you're talkin!!!! I have the 7x64 Brenneke and the .280, guess I don't really need the 7x57 or 7-08.....but then again.....it would really be cool to own em all 8) .....naw....well.....maybe!!!! :eek:
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Offline Mac11700

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« Reply #16 on: April 10, 2005, 08:23:43 AM »
Who you kidding Quick... :) ..you would "Have" to have one of each...

Thanks While99...this was what I was looking for...

Mac
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Offline quickdtoo

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« Reply #17 on: April 10, 2005, 08:34:34 AM »
Yeah, I know!!!  :-D   Just don't tell my wife!!! :eek:

Tim
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Offline Fred M

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re-chamber
« Reply #18 on: April 10, 2005, 09:30:24 AM »
The .456 shoulder wont even make the 7x57AI. You would definitely need a reamer with a .459 shoulder.  in no way will a 7x57 work. the body tapers are not even close. Besides when you measure a fired case you have to consider sping back up to one thou.

It is most difficult to use the 308 body taper Alpha .01025" per inch for any improved AI's based on that case in an existing chamber. That is because the 308 has an Imp body taper already. Keep things in 7-08 or like the man said get a 280.

I had a 243 Rem mountain rifle barrel that had a shoulder of .459. that is 5 thou Over size.
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Offline Chainsaw

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« Reply #19 on: April 10, 2005, 03:48:52 PM »
Fred and Mac, after my 11th grade tests results came back in 1970, I finally got an A in Math after many years of spelling it with an E. Hope this helps you guys out :grin: .........Chainsaw
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