Author Topic: 8mm-06  (Read 2864 times)

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Offline mrussel

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8mm-06
« on: June 05, 2010, 08:40:32 PM »
I think Im missing something about this cartridge. From what I can see,the hotter loads for a 8mm Mauser have exactly the same performance as a 8mm-06. I dont understand why someone would do this,especially considering that a 30-06 case can be easily resized and used as an 8mm Mauser.

 What confuses me is,if you want a hotter 8mm load,why does using a 30-06 case with the neck sized up to 8mm get you there. Why not just load the 8mm hotter. If you take into account seating depth,I dont even think there will be much volume difference,but even if there was,you could load a 8mm hot enough to be dangerous if you were crazy enough so whatever you could load the 06 for you should be able to load the Mauser for too. Is the 06 brass somehow more robust or something? If that's the case,wouldn't resized 06 brass be just as good without rechambering?

 Edit: Doing a little more reading,I see that 8mm is rated at 57,000 psi and 30-06 at 60,000 psi and it is said that the brass is stronger,and the military brass is even thicker. Still,that does not seem to justify the difficulty in rechambering the gun. It would seem to be easier just to resize 30-06 brass to 8mm and then load to 30-06 pressures. There will be a little difference due to the different volumes,but I have a hard time beleiving it could be enough to justify the change unless you happen to be a gunsmith and HAVE the 30-06 reamer and all the tools.

Offline Mikey

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Re: 8mm-06
« Reply #1 on: June 06, 2010, 02:24:01 AM »
Nope, not missing anything.  As I understand it, the 8mm-06 was developed after WWII when there wasn't any 8mm ammo for those Mauser 'bring-backs' and the barrels were simply rechambered to a 63mm length 06 cartridge with a 8mm bore so they could be shot.  The prevailing theory back then was that the Mauser was a weak action or that some of the war trophies were WWI rifles with a .318 bore but that none the less it was not safe to load them to their European potential, hence the weak US made 8mm ammo later on.  

So, although rechambered the 8mm-06 loadings really did not go beyond what US factory 06 ammo pressure levels and although popular with some, the cartridge remained a 'wildcat' and was never adopted by US ammo makers.

The US continued to make weak 8mm ammo for a couple of decades until the hotter European ammo, which was loaded to original Euro specifications, finally came to this country and returned the 8mm to the whomper it really is and when that happened the 8mm-06 went to the back of the bus, which is a shame, because you could really turn that cartridge into something closer to the 8mm Magnum in capability.

The 57mm case is a very effective cartridge size but I gather the 63mm length 06 is a bit over-bore, which I never really understood, but if you open the 06 to a 8mm you should be able to get to the same level performance as if you had opened it to .338 or .35.  I think that if I was going to play I with a 8mm-06 I would load it up to the performance levels capable from a 63mm length case.  jmtcw.

Offline Dances with Geoducks

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Re: 8mm-06
« Reply #2 on: June 06, 2010, 07:49:41 AM »
Ive built two 8mm-06AI rifles.
The difference is using 06 cases cut down to 8x57, you have to anneal the cases.
Making the rifle 8mm-06 you can use the 06 case, and fire form it to your chamber.
Making it 8mm-06AI, you can load them hotter, and wont have the neck wear you do on either of the others.
You only gain about 5% load from 8x57 to 8mm-06 to 8mm-06AI.

Knowing what I know now after doing it. I would have just made the 8x57 cases from 06 cases.

I traded both rifles for a Marlin lever, its more fun, and not as heavy.

Offline yooper77

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Re: 8mm-06
« Reply #3 on: June 06, 2010, 09:26:50 AM »
I think Im missing something about this cartridge. From what I can see,the hotter loads for a 8mm Mauser have exactly the same performance as a 8mm-06. I dont understand why someone would do this,especially considering that a 30-06 case can be easily resized and used as an 8mm Mauser.

 What confuses me is,if you want a hotter 8mm load,why does using a 30-06 case with the neck sized up to 8mm get you there. Why not just load the 8mm hotter. If you take into account seating depth,I dont even think there will be much volume difference,but even if there was,you could load a 8mm hot enough to be dangerous if you were crazy enough so whatever you could load the 06 for you should be able to load the Mauser for too. Is the 06 brass somehow more robust or something? If that's the case,wouldn't resized 06 brass be just as good without rechambering?

 Edit: Doing a little more reading,I see that 8mm is rated at 57,000 psi and 30-06 at 60,000 psi and it is said that the brass is stronger,and the military brass is even thicker. Still,that does not seem to justify the difficulty in rechambering the gun. It would seem to be easier just to resize 30-06 brass to 8mm and then load to 30-06 pressures. There will be a little difference due to the different volumes,but I have a hard time beleiving it could be enough to justify the change unless you happen to be a gunsmith and HAVE the 30-06 reamer and all the tools.

It depends on the action not the brass.  I have re-sized 30-06 Springfield into 8mm Mauser ammo for years, but I always stuck to manufacture loading data.

I currently reload my 338-06 A-Square with 30-06 Springfield brass.  If I wanted a modern 8mm cartridge I would re-bore a 30-06 Springfield into a 8mm-06 because it just makes more sense.  Easy reloading and less trimming, Ackley Improved cartridges grow less between firings, so an 8mm-06 Ackley Improved is a good choice.

yooper77

Offline mrussel

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Re: 8mm-06
« Reply #4 on: June 06, 2010, 09:46:34 AM »
Ive built two 8mm-06AI rifles.
The difference is using 06 cases cut down to 8x57, you have to anneal the cases.
Making the rifle 8mm-06 you can use the 06 case, and fire form it to your chamber.
Making it 8mm-06AI, you can load them hotter, and wont have the neck wear you do on either of the others.
You only gain about 5% load from 8x57 to 8mm-06 to 8mm-06AI.

Knowing what I know now after doing it. I would have just made the 8x57 cases from 06 cases.

I traded both rifles for a Marlin lever, its more fun, and not as heavy.

I see the percentage increase from the 8mm to 06 IS about 5%. Are you saying that you would just use the 06 brass with 06 pressures or are you saying that you would live with the slightly lower pressure of the 8mm?

 I would guess of course,in reality that around 5% (just a WAG) is the range of pressures you would get ANYWAY with working up a load and relying on the bullet speed as a indicator of when your done,maybe more. I suspect the 5% pressure is something that would be hard to notice. Ive noticed most of the hand loading literature lists velocities at the high end that are very similar if not identical. One question I have is whether the 06 brass is going to end up being significantly weakened by the forming and annealing process. If you start crunching the numbers,it looks like the actual internal volumes,especially after seating bullets are very close to the same. Does anyone off hand know what the internal volume of a typical 30-06 is when loaded? For that matter,does anyone know how much variation in a cartridge you can expect to see?

 
 Now,AI on the other hand,I can see the point. There are significant,although subtle changes to the cartridge. It seems to me that 8mm-06 is a solution in search of a problem,as 8mm is already so close to an 06,I really don't think there is a practical difference,AI on the other hand is trying to get that slight improvement over a 06 in the 8mm. Not sure if its worth it or not to me,but there is defiantly a point to it.




Offline mrussel

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Re: 8mm-06
« Reply #5 on: June 06, 2010, 10:18:12 AM »


It depends on the action not the brass.  I have re-sized 30-06 Springfield into 8mm Mauser ammo for years, but I always stuck to manufacture loading data.

I currently reload my 338-06 A-Square with 30-06 Springfield brass.  If I wanted a modern 8mm cartridge I would re-bore a 30-06 Springfield into a 8mm-06 because it just makes more sense.  Easy reloading and less trimming, Ackley Improved cartridges grow less between firings, so an 8mm-06 Ackley Improved is a good choice.

yooper77

 That certainly makes sense (although in pistol calibers the brass does often have something to do with it,for instance 45 super brass is much more robust than 45acp,yet the external dimensions are identical),but it just seems to me that due to the extreme degree of similarity between an 06 and an 8mm to begin with,if a rifle can be re-chambered to 30-06 or 8mm-06,then it could take those same pressures even if the cartridge was left the same,while if a rifle could NOT take the pressures in its original 8mm Mauser form,then it would be unsafe to convert to either 06 and doing so would be asking for a face full of metal fragments.

 This of course is all theoretical as,since the internal volume differs (although not as much as you would think if you throw the numbers into a calculator) you couldn't just use an 06 load in a 8mm and call it done and we have no way to measure pressures,although if I had no 8mm load data at all (like it was back in the day),I guess that's exactly what I would do,although I would start with a light load and work from there.

 Its kind of interesting to consider what you would do if you had no 8mm components or data at all. My first instinct would be to get some 30-06,and take them apart and measure the powder charges. Id then try to make a die to swage the bullets to 323. Then re-size the case,put them all back together,with a reduce powder charge,at least until you figured out how much your max load would be,and you would have 8mm. I guess if I had to go through all that,a change that made it easier to put 06 cases in with minimal resizing might start sound really good.

Offline Dances with Geoducks

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Re: 8mm-06
« Reply #6 on: June 06, 2010, 03:02:20 PM »
Cutting down an 06 case to 8x57, you will still be using the 8x57 load data.
When you rechamber to 8mm-06 is when you can warm them up the 5% per wildcat step

Offline mrussel

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Re: 8mm-06
« Reply #7 on: June 08, 2010, 06:12:06 PM »
Cutting down an 06 case to 8x57, you will still be using the 8x57 load data.
When you rechamber to 8mm-06 is when you can warm them up the 5% per wildcat step

 Im still not really convinced of why its a great idea. It seems to me that if its not safe to load a 8mm to 30-06 pressures,the changing the chamber dimensions a tiny bit and loading up a cartridge based on a 30-06 isn't going to be safe either. It just seems that if one is safe,the other would be too,and if one is not,neither would be. I can see the 06-AI being a different matter as there are some slightly more significant changes. It would also seem that the AI would be the option regardless of whether you think the 06 is a good idea,as,if you do 8mm-06 its not going to cost any more than the AI (assuming you find a smith with the right reamer) and its clearly superior.

Offline mrussel

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Re: 8mm-06
« Reply #8 on: June 08, 2010, 06:15:28 PM »
Cutting down an 06 case to 8x57, you will still be using the 8x57 load data.
When you rechamber to 8mm-06 is when you can warm them up the 5% per wildcat step

 Im still not really convinced of why its a great idea. It seems to me that if its not safe to load a 8mm to 30-06 pressures,the changing the chamber dimensions a tiny bit and loading up a cartridge based on a 30-06 isn't going to be safe either. It just seems that if one is safe,the other would be too,and if one is not,neither would be. I can see the 06-AI being a different matter,from a performance standpoint as there are some slightly more significant changes,of course I would also think that if a 8mm loaded to 06 pressures is not safe,then the AI would be even MORE unsafe. It would also seem that the AI would be the option regardless of whether you think the 06 is a good idea,as,if you do 8mm-06 its not going to cost any more than the AI (assuming you find a smith with the right reamer) and its clearly superior.

Offline mcwoodduck

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Re: 8mm-06
« Reply #9 on: June 08, 2010, 06:29:03 PM »
Nope, not missing anything.  As I understand it, the 8mm-06 was developed after WWII when there wasn't any 8mm ammo for those Mauser 'bring-backs' and the barrels were simply rechambered to a 63mm length 06 cartridge with a 8mm bore so they could be shot.  The prevailing theory back then was that the Mauser was a weak action or that some of the war trophies were WWI rifles with a .318 bore but that none the less it was not safe to load them to their European potential, hence the weak US made 8mm ammo later on.  

So, although rechambered the 8mm-06 loadings really did not go beyond what US factory 06 ammo pressure levels and although popular with some, the cartridge remained a 'wildcat' and was never adopted by US ammo makers.

The US continued to make weak 8mm ammo for a couple of decades until the hotter European ammo, which was loaded to original Euro specifications, finally came to this country and returned the 8mm to the whomper it really is and when that happened the 8mm-06 went to the back of the bus, which is a shame, because you could really turn that cartridge into something closer to the 8mm Magnum in capability.

The 57mm case is a very effective cartridge size but I gather the 63mm length 06 is a bit over-bore, which I never really understood, but if you open the 06 to a 8mm you should be able to get to the same level performance as if you had opened it to .338 or .35.  I think that if I was going to play I with a 8mm-06 I would load it up to the performance levels capable from a 63mm length case.  jmtcw.
Reminton makes a whimpy loaded 8X57 because earlier 8mm was .318 current 8mm is 323 and they did not want to harm the earlier 88 action by trying to squeeze a 323 bullet at 3,000 FPS through a 318 tube and the weaker 88 action that had an open top like a manlicher rifle.
And as others said it was easier to rheem a 8X57 out to 30-06 case length and load a 323 bullet.  with out having to go throug hte expence of rebarreling the action to any of the calibers that would fit in the 98 action.

Offline CGPAUL

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Re: 8mm-06
« Reply #10 on: June 15, 2010, 07:15:22 AM »
The idea of the 8mm06 after the war, was the fact that 8x57 brass was hard to come by, and guys wanted to use their Mausers...so recut the chamber, neck up the 06 case to 8mm, and go. Most folks then did not have the money to rebarrel, so this worked. And an added benefit over the original chambering was a little more snort.
That practicallity made sence. For the generation now, going with a new barrel would indicate the 8mm06 AI, because the cartridge is a handloading proposition anyway, the added case volume adds velocity.
I have both the 8x57 and 8mm06AI. I see an increase of 5-7% in velocity gain with the AI, both cartridges loaded to max potential. If that floats your boat, go AI.
I used the 8x57 in Africa this past fall on PG, shooting wildebest, springbok, reedbok, and gemsbok. All were killed with one shot. Load was a175 grn Sierra push by 4320 at 2850 fps, cronied. The thing was like a lazer, point and shoot, dead animals. Longest shot was 300 yrds, called by the PH. Closes was 80 yrds.
IMHO, both are great cartridges, but, loaded to eaches potential, will not do anymore or less than a number of others.