Home Forums Hunting & Shooting Ask The Gunwriters Finn Aagaard on the 7x57

CCCC,

Actually, according to some basic rules of internal ballistics, the 8x57 is capable of about 7% more velocity than the 7x57 when using bullets of the same weight, everything else being equal--which means the same pressure, the same barrel length, etc. This may not sound like much but amounts to around 200 fps in loads using 150 to 175/180 grain bullets.

Have published a lot of information on this subject, and other basic rules. In fact, a chapter on it titled "The Rules" has appeared in two of my previous books, and will also appear in the soon-to-appear GUN GACK 1V, THE LITTLE BOOK OF RIFLE LOADS THAT WORK--partly due to reader requesting it be reprinted again.

The 8 x57 cases I own look waaay different than the 7 x 57 cases I own.

Makes me ponder if there isn’t some German skullduggery development of the modern 8x57.

My uncle told me years ago not to bother ackley improving my dads 8 x57 model 98 Mauser because them Germans must have known sumthin

Angus,

You must have a different definition of "waay" different.

The only differences between the 8x57 and 7x57 cases that would be obvious to the naked eye are the length the diameter of the neck (which is obvious from their names), and the length of case body from the head of the case to the rear of the shoulder, which is about .1 inch longer in the 8x57.

The diameter at the rear of the shoulder in both cases is within .001 of .43 inch/ The shoulder angles are both just about 20 degrees, and the overall case length differs by about .01.

No, the 7x57 is NOT exactly the 8x57 necked down, like the .270 Winchester is the .30-06 necked down. But the dimensions are so close any difference in powder room would be due to the heaviness of the brand of brass, not case dimensions.

Wiki pedia states the 7 x 57 holds 60 grains ?water has no parent case.

The 8 x 57 holds 63 grains
It’s parent case is the 88 patrone? Kinda like tequila.

It says Paul Mauser development of the 7 x 57 was 1893.

I will post pictures when I get home.

They look different to me.

You might be smoking something.... A "gram" is 15.4 grains.

Plus, Wikipedia is often FOS. Am sure whoever posted that "measured" capacity by filling the cases to the mouth--which is NOT the most accurate way to measure capacity. Instead it should be done with a bullet seated. Even then, in different brands of specific 7x57 and 8x57 cases (or .270 or .30-06 cases) powder capacity will often vary 3 grains.

And three grains difference in powder capacity in that size case means just about zip, since as I've explained before, any difference in powder room results in about 1/4 as much in velocity, when both cases are loaded to the same pressure. 63 grains is 5% more than 60 grains, which means a 1.25% difference in potential velocity. This means a 35 fps difference in velocity with loads around 2800 fps. Most handloads will vary around 35 fps when firing 5-shot strings.

No I changed it to grains.

The neck length on the 7 x 57 appears much longer.

I will post photos in a couple of weeks when I get home.

I don’t believe they are the same parentage of case.

Then you don't know what you're talking about.

I have a 7x57 and 8x57 case sitting right next to me, and yes the 7x57's neck is longer--by .066 inch.

You also might want to do some actual research on the history of the two rounds, instead of jumping to conclusions on the basis of your "eyeballing".....

So they are the same case?

I thought the 270 was a necked down 3003?

I was just fixing to say them .270 cases make dandy 30Govt 1903 ctgs! 😁

That’s how I make mine also!

👍👍👍👍

I think that MD said that the cases have the same OAL, but that the body of the 8x57 is longer from the bottom of the case to the bottom of the shoulder, and the neck is correspondingly shorter than the 7x57 case

When I compare the 7x57 to 8x57 case dimensions, the overall length of the cases is the same, 57mm, but the length from the bottom of the base to the bottom of the shoulder is 43.84mm for the 7x57 and 46.2mm for the 8x57, a difference of 2.36mm. Since the overall case lengths are the same, 57mm, the difference of 2.36mm is accounted for my different shoulder angles and lengths of the shoulder and neck. The 7x57 has a shoulder length of 3.57mm and a neck length of 9.59mm, while the 8x57's measurements for those portions of the case are 2.7mm and 8.1mm respectively.

Same basic parent case, but after being run through different dies they have different dimensional specs within the shared overall length. IOW, you could make shootable 7x57 cases from 8x57 donor brass or shootable 8x57 cases from 7x57 donor brass.

I'll save Angus the trouble of posting a photo: On the left is the 8x57, and on the right the 7x57. As noted earlier, all but two of their case dimensions are just about identical. The 8x57's body from the case head to the shoulder is about .1 inch longer, and the case necks obviously have different diameters. But the head and body diameters are just about identical, as is the shoulder angle.

I took two other fired 8x57 and 7x57 cases and weighed them, then filled them with water to the mouth and weighed them again. The 8x57 case held 61.0 grains of water, and the 7x57 case 59.8 grains.

Anybody who's done much research on the two cases knows that Paul Mauser was involved in the development, along with other folks, of the original version of the 8x57, designed for the Gewehr 1888--and the 7x57 was developed by his own Mauser company in 1892. It's not a vast coincidence that they're so similar.

Thanks mule deer.

But to my eye ballz they look waaay different.

Angus,

Here are two cartridges that look waaay different:

Itz all in dem eye ballz 👁

In a situation where differences are so slight, it is not my style to tell someone that "they are smoking something" or "you don't know what you're talking about". The memory says that the 8x57 case affords about 1% more capacity than the 7x57 and that past shooting/chron experience has shown that little difference in velocity with the same bullet weights. If your basic rules of internal ballistics say that the "capabilty" of the 8x7 yields 200 fps more velocity, so be it. My old chrono did not measure capability.

CCCC

Getting scolded last night got me re reading the 8 x57 on the terminal ballistics research site.

I found it fascinating.

What’s interesting about these two cartridges is the 7 x 57 ( which is an original cartridge design) wildcatted into the 257 roberts.

The 8 x 57 (whose parent cartridge is the original rim less cartridge invented ) wildcatted to bigger diameter bores.

It’s fascinating also how the actual diameter of the 8 x 57 changed over time and the variation in performance between the Mauser model 98 s used.

Now I gotta study the 7 x 57 more.

But I believe the more a column of powder is bottlenecked before the bullet. The less efficient that column of powder becomes.

well in this small disagreement there was a positive side for me and maybe some others ,i learned a little more history on these two fine old cartridges . the bad thing about these 2 grand old cartridges is the world of gun and ammo manufacturing these 2 cartridges are almost lost for good.