I can't decide. I have two 8mm barrels almost the same contour. They are both stainless, 10" twist. One is Douglas and the other is Lothar Walther. The Douglas is rough turned, and the LW is nicely polished.

The removable pilot of my (new & sharp) reamer fits the Douglas bore, but the bore is too tight on the LW, and the pilot won't go in. PTG will supply the correct pilot, but the point is that the bore on the barrels is not the same. The LW is tighter (smaller).

I want to use both barrels for something, but next on the list is the 8mm wildcat. I was thinking of a 8x57 with the Douglas. I bought the LW barrel for the wildcat project, but now I hesitate, second guessing my choice. Part of the problem is that if I don't use the LW barrel on the magnum wildcat, then what am I going ot use it for?

What would be your choice of barrels?

KB

You may find that with usual powders available in the USA that 8mm-06 is actually better!

In Europe with Vectan SP7 you don't worry about the 8 x 57 and case capacity...but with US powders it can be a problem.

The 8x57 is capable - the Germans were doing it in 1903 - of a 154 grain bullet at 2,880fps. But probably not even today with bulkier US powders!

Either barrel in the wildcat will give you totally adequate hunting accuracy.
The second rifle in 8X57 sounds like an absolute winner. roger

quote:

Originally posted by 22WRF:
What is the industry standard for over and under the correct bore diameter? plus or minus ...

If it (the Lothar Walther) barrel were mine I would make sure it is within industry standards. If it is I would use it the way I planned to use it.

The LW web site shows:

8mm-10"
shank diameter 1.260
length 26.3
grooves 4
land diameter .311
groove diameter .323
twist rate 10.0

I posted this elsewhere, but it didn't raise any interest, since they are talking nostalgic stuff there.



8x57 / 8x60S / 8mm-06 / 323 Hollis / 338WM

quote:

Originally posted by bartsche:

The second rifle in 8X57 sounds like an absolute winner. roger

roger,
This 323 project has been on my list for a long time. It needs to be finished or go away. I have the action, stock, barrel, dies, reamer, and plenty of 308 Norma brass. and lots of 8mm bullets and powder.

I tried forming some 323 Hollis cases from 300 WM brass I picked up at the range. It was my first attempt at case forming where the shoulder had to be moved, and I just used the FL size die. The shoulders were krinkled a little, but I think they will fill out with the first shot. I probably won't have to ever use anything but the pristine Norma stuff anyway, which simply necks up.

Of course, it's an estimate now, since I havent been able to try it, but I think the magnum can cover velocities from about the 8x57 through the 8x68S, with basically two powders - H4895 and H4350. Hodgdon says H4895 can be safely loaded to 60% of max, so that's a pretty wide range of velocity. For top loads, I'm estimating that H4350 will be among the best for this cartridge. I have about 16 pounds of the stuff. Plus about 16 more pounds of IMR 4350. I worry about the stuff going stale. A magnum is a good way to burn lots of powder.

KB

I once had a mauser rebarreled with a Douglas, #2 contour in 8x57. That was a shooting son of a gun. I gave the gun to young boy, on his 12th birthday, who lost a leg from the knee down due to cancer.

IMR 4064 and Nosler Ballistic Tips.

quote:

I gave the gun to young boy, on his 12th birthday, who lost a leg from the knee down due to cancer.

Damn fine gesture on your part Airgun.

Take your barrel to a trusted smith, or Tool and Die shop. Ask them to determine your land diameter with pin gauges. This will determine what your pilot should be and whether the barrel is just slightly tight or excessively tight.

Worse things have happened, but I would be of the opinion that if Lothar Walther shipped it, I will shoot it.

At this time, I agree with you. I'm pretty sure the barrel is within spec. I talked with PTG today, and got info about pilot sets for the 8mm, and the actual specs of the pilot furnished with my reamer. I was told over the phone that the pilot is .315, which I confirmed with my calipers. LW web page says .311 for bore. The pilot fits into the Douglas barrel, and is a no go in the LW barrel.

I'm never going to know what to really think of a LW barrel, until I try one. To my thinking, messing with a wildcat in the first place is taking a risk. The choice of barrels is always a risk - given the cost relating to outcome factor. In my memory, I've not yet had a bad custom barrel. I have had some custom projects not turn out well, but it wasn't the barrel that was the problem.

The plus side of it is if the LW barrel is a little tight, then this wildcat is a handload only deal anyway. I'll discover max by working up. So that won't be a problem, since handloads will be for this rifle only. It could be a problem with a standard cartridge, but probably not.

If it doesn't turn out - oh well - I'll rebarrel it, and mark it down to experience.

However, the thing that has come to my attention lately is the cost to have a barrel installed by a good gunsmith. It's getting so that it's a concern, especially for a guy with several projects on his list. Looks like I need to sell some projects to make funds to finish others.

KB

More info. I should have thought of this before. I took the reamer and tried the pilot in other 8mm barrels - two Shilen, one PacNor, and one unknown make. It also fit into the Douglas. None were a sloppy fit. The pilot is .315"

With this new info, can someone provide input as to the significance, if any, since the std pilot provided by PTG works with all those makes of barrels, and does not fit in the LW barrel. I can only guess at the significance.

Thanks,
KB

Consider an old European Classic; the 8x68S.

Really neat cartridge, case capacity 86.54gr of water. Factory loading is a 170gr SP at 3000fps.

Rich
DRSS

I have considered the 8x68S, and thoroughly rejected it - not because it's a bad or inferior cartridge, but because of the brass issues, and finding an action to feed it through.

This 8mm wildcat (323 Hollis) practically duplicates the ballistic performance of the 8x68S, but also practically eliminates the action/feeding, and brass availability issues.

Besides, I have dies, reamer, action, brass, etc. for this project, and I wouldn't abandon it now for a 8x68S.

Although I care about nostalgia, collector's value, and tradition, I care foremost about it working properly, and keeping it simple. The cartridge itself is only part of the package as a whole. It always sort of miffs me, all the discussion of the merits of a certain odd-ball cartridge, however correct that may be, looking at the specs of the cartridge, but almost completely overlooking the very significant problem issues with the platform to feed it through.

If I had an action that would feed the 8x68S most excellently, then most of the problem with that cartridge would be solved, except for brass.

KB

quote:

Originally posted by Idaho Sharpshooter:
Consider an old European Classic; the 8x68S.

case capacity 86.54gr of water.

Rich
DRSS

I just weighed the case capacity of water in the 308 Norma brass necked up to 8mm.

85.2 grs Close enough for me.

I tried it again, with another piece of brass, and a dry pan, and got 87grs even.

Looks like some variation, and maybe not so scientific.

Anyway, I'm happy about that comparison. I had it figured to duplicate the 8x68S, but now I know for sure.

I am also interested in comparing that to the case capacity of water in the 325 WSM, if someone would care to do that measurment on sized or new brass.

Thanks for the info.

BTW, the CIP specs for the 8x68S call for about 11" twist. I'm using 10" twist. I'm not as much interested in what a 170gr bullet will do (in this cartridge) as I am a 200gr Nosler Accubond, or perhaps a 220 gr Sierra, or the 200 or 220 gr Swift, or maybe a 180 or 200 gr Barnes TSX. Also, I have several hundred of the Hornady 220gr and the 220gr Remington bullets. More than I can shoot is several years, if I shot only this rifle.

I really want to finish this project, thus I want to resolve the barrel choice decision. There's broad knowledge here that I was trying to tap into.

KB

quote:

I am also interested in comparing that to the case capacity of water in the 325 WSM, if someone would care to do that measurment on sized or new brass.

I don't have the brass but QL calls it 81.8.

Most guys who have 325 WSM's love them. Most gunsmiths that I know do not want to try and convert standard actions to any of the WSM's as they are very fat and are a pain to get to feed reliably.

I'm sure this crossed your mind but does the barrel with the .311 bore dia. have a .324 lands dia. or a .318 lands dia.? roger

Roger,
See above post with the picture. It gives the barrel specs per LW. Groove = .323

airgun,
I think it's a good thing that the old actions are not being converted to the 325 WSM, aside from feeding issues, that cartridge operates at a higher pressure than those old actions were designed for, as far as I know.

Besides, there are several of good rifles factory chambered in that cartridge, and there are several good modern actions made specifically for the WSM cartridges, such as practically any of the Remington clones, the Rem 700, and the Montana 1999, etc. etc. I think it's silly to convert an old action to the WSM.

BTW, I would rather have a 325 WSM than the 8x68S. When I started my wildcat, the 325 WSM had not yet been introduced. IMO, the 325 WSM is the best of that series, by a good margin. It may be the best of all the 8mm cartridges - ever - and that's saying a lot, and certainly arguable.

KB

KB,
I have used pin gages in many brands of barrels. I proved to myself and my buddies that the bore diameter stamped on the barrel is a mean and not exact. Most will be _+ .0005 and be within their specs. I have pin, Deltronic, gage sets for each bore diameter that I chamber. Example for a 6mm the mean will be .237 and the set will have 12 pins in .0001" increments smaller and the same larger. In other words from .2358-.2382. Believe it or not the LWs that I have done have run looser than that. Your LW barrel could only be a tenth or two under and I don't see a problem. You do need to know inorder for you to get the proper bushing. I have 6-8 bushings for each bore size.
Butch

quote:

Originally posted by butchlambert:
KB,
the bore diameter stamped on the barrel is a mean and not exact. Most will be _+ .0005 and be within their specs.

Your LW barrel could only be a tenth or two under and I don't see a problem.

You do need to know in order for you to get the proper bushing. I have 6-8 bushings for each bore size.
Butch

Butch, I have edited your post above by selecting out the specifics, in sections, to help me understand, but I still don't. My problem is with the decimal place.

I'm reasonably sure that the pilot on the reamer is .315", because that's what PTG says and the drawing they provided, and my calipers confirmed that. I don't have a micrometer or I would use that.

The pilot is a no-go into the LW barrel, so it's definately smaller than .315, measured off the lands.

LW says the barrel is .311 inside the lands. (+ or - .0005)

Since the pilot fits tightly inside all the other 8mm barrels I tried, that means, for practical purposes, I can say they are at most .3149 off the lands. Which means that the LW barrel is tighter by .002" to .003", compared to the other barrels.

I have to presume that all the barrels are .323 measured off the groove (+ or - .0005") LW web site says their 8mm barrels are .323 groove. Thus, it simply means that the lands are taller in the LW barrel, compared to the others. Which also means that the lands will cut deeper into the bullet (.323) as it passes through the barrel on the LW barrel, compared to the other barrels. .323 bullet through .311 lands means .012 cut into the bullet as it squeezes through the barrel. (or is that .006 for each side of the bore?) Spelled out, I think that's said twelve thousandths of an inch (or six thousandths?). I think there are several (maybe all) hammer forged barrels that have grooves that deep, but no button rifled US made barrels that deep.

As far as finding the right pilot, that won't be the problem. I already talked with my gunsmith about that, and he has a set of pilots for 8mm, and feels sure one will fit the barrel.

He also says he has never used a LW barrel, so he can not report good experience or bad experience. He doesn't know.

KB

Kabluewy:

I think that what you are seeing may be the difference between a German '8mm' and the generic European 8mm. The 8mm Mauser was never called that by the German military: they called it the 7.9mm. It is listed in the 1925 Kynoch catalog as "7.9 mm (.311) Mauser". My understanding is that the nominal bore diameter was .311" (7.9mm), and groove diameter was .321", with a bullet diameter of .318".

On the other hand, the Austrian 8x50R Mannicher and 8x56 Mannlicher-Schoenauer were true 8mms, with nominal .315" bore diameter and .323" groove diameter. The Kynoch catalog lists these as .315s (along with an "8 mm (.315) Mauser" for the later S bore rifles).

Things became complicated for two reasons:

1) When Germany adopted the high velocity S Patronen, they incresed the groove diameter to .323", without changing the bore diameter. Therefore, their 7.9mm rifles (and machineguns) fired the same diameter bullet as 8mm small arms of some other nations.
2) For some reason, when the 7.9mm Mauser was adapted to commercial use, the manufacturers chose to call it the '8mm Mauser' rather than adopting the military designation.

From the information that you present, it would seem that your LW barrel is a 7.9mm, while your Douglas is an 8mm, though both are designed for use with a .323" bullet diameter. If I were in your situation (I wish ), I would follow 'tradition' and use the LW barrel for the 8x57 and the Douglas for the magnum.

Cheers, Al

Thanks ClassicAl. That helps fill in parts of this puzzel, and makes sense to boot, and is interesting also.

It's only a coincidence that I have all these parts together at the same time, and my curosity got me going. Each new fact led me to wonder, and then to the next.

Thanks again.

KB

KB,
The decimal places are exactly where I wanted them to be. Without pin gages it could be as little as .0002 smaller and you wouldn't know it. You need to take it to a smith or shop with pin gages to find out what you have in your hands. You can't measure pin gages or bushings with your calipers accurately. ClassicAl may very well be right in his assessment.
Butch

Butch,
I appreciate your feedback too. It's good to get perspective. I understand that it is practically impossible (or maybe not likely) that I can accurately measure the pilot with my calipers. That's why I wish I had my micrometer out of storage.

But the measurment of the pilot with the calipers was just to sorta confirm that it wasn't off a lot from what PTG told me, and what their spec sheet shows. They said the .315 pilot is the std provided with the various 8mm reamers, and different pilots are sold in a kit, to cover most of the variants.

So, using a pilot that I am reasonably sure is .315, trying it in six different 8mm barrels, gave me useful info. The pilot fit all the barrels except the LW.

In this situation, I actually don't need to know the exact measurments of the LW barrel, down to the ten-thousanth of an inch. If I decide to use it for the project, I'll just leave it up to the gunsmith to use the correct pilot, whatever it is. IF (big if) it's exactly what LW shows on their web site, the pilot will be just small enough to fit in the barrel, .311 measured off the lands.

I know enough about the measurments to cause me to wonder about the significance, if any. Why would all the US barrels I tried be .315, and apparantly that's the common spec, or PTG would not choose that pilot as std?

If the affect of the LW barrel's lands results in perhaps a pressure spike from the tight squeeze, or excess trauma and distortion of the bullet messing up accuracy, then it would be useful to predict that in advance. One could reasonably presume that LW thought of that already. However, I suspect that I'm gonna just have to try it, and see for myself, at the range. I could perhaps get some useful info from the gunsmith as to any discoveries of the workability of the steel, or any issues he discovers in cutting the threads and chamber. Accuracy, velocity potential, copper fouling, ease of cleaning, duration of break-in, and that type of info, etc., with any certainty, will probably have to come from actually shooting the barrel. At this point, I'm curious enough to try it. Even if it is a mistake, it can be fixed.

KB