What I am seeking is input on the feasability of rechambering a M98K to 8X68S.

The action in question is in like new condition with all matching #s. The barrel is like new and I doubt if it has seen many rounds through it as bullets seated to a COL of 3.150" result in the bullet being off the lands about .010". The action is like a German virgin (gutentight) I do not wish to rebarrel this action as the barrel is in such good condition and I like the ballistic characteristics of the 8mm bore. (Better bullet mass and energy than a .308, better velocity and flatter shooting than a .338) The 8mm bullet choices are much better these days and I am already loading for 8X57 and 8mm-06 Ackley Improved. I am particularly fond of the Nosler 180gr Ballistic tip (for deer sized game) and the Nosler 200gr Partition (for anything larger I would care to hunt) I believe the ballistic performance of this round is on a par with the 8mm Remington Magnum (2936fps with 200gr Nosler Partition in Hertinberger factory ammo) in a cartridge that will allow a COL about .200" shorter than an 8mm Rem Mag, without having to deal with the useless belt on the case. According to my calculations a COL of 3.40" with the 200gr Partition will not impinge on the powder space of the cartridge case appreciably. (about the same as the 8mm Rem Mag @ 3.60" COL) I have found a source for brass (Old Western Scrounger) manufactured by Hirtenberger @ less than $50 per 100. Dies are availible from several sources. I would like input on the following:

1)What is the practical COL limit for a "standard length" M98K action without extensive (expensive) gunsmithing? I can achieve 3.375" magazine length with nothing more than mill file work on the front and rear magazine walls and slight alteration of the bolt stop. I think I could get another .150" by extending the front of the magazine, and some milling and die grinder work on the feed ramps. This would yield a magazine length of 3.525" alowing a COL of up to 3.50".

2)Can the issue barrel be safely rechambered to 8X68S? Other than removing the issue sights, plugging the locater holes and blending the "flat" where the issue sights are sweated on with the tapered portion of the barrel, the barrel profile will remain unchanged. The barrel diameter @ the chamber area will be .950" with a shoulder diameter of .4695" leaving a chamber wall thickness of .235". Will this withstand the pressure with a resonable margine of safety? What is the pressure level of a load similar to the Hirtenberger factory load? (2950fps +or- with a 200gr bullet)

3)Is it practical to open up the bolt face to accept the large base diameter of the 8X68S cartridge? Reamer base diameter is .5248. What is the rim diameter?

4)From the limited information I have read on this round, it was designed for M98 actions. What will feeding reliability be like? How much modification to the feed rails will be required?

I am looking to get the most bang for the buck while utilizing the perfectly good barrel already there.

Shamless ploy to move this topic to the top to get a respose.

Wildcat.

The Hornady Handbook of Cartridge Reloading(3rd edition) includes a case dimension drawing. The rim diameter is .512", the base dia is .524" and the case length os 2.658".

The recommended COLs are: 125 grs-3.325",150 grs-3.400", 170RN-3.25, 220 gr-3.425".

I have been hot to get one of these from the time I saw one in Namibia. I hunted with a land owner who had one on a 98 action. I believe his was rebarreled. I guess you don't need much pushing towards this cartridge but I will provide a quote from my PH, "The 8x68 is a REAL gemsbok rifle. Even if you hit him wrong you will get him with an 8x68." He guided a great deal of German hunters so I believe he knew what he was talking about.

Jason

barrel dia around the chamber is only 1.10 inch , that very light for big case as 8x68S , next point that a long cartridge and you need lot of modification on receiver and magazine box.

8x68S case are very costly and very hard to reload .

a nice conversion not costly with plenty of case available ( 7 REM MAG or 338 WIN ) and lot of power is rechamber in wilcat 8/338 WIN or 8/7 REM MAG ( that the same ) , just run the 30/338 reamer and neck and throat in 8 mm

realoding is done with Redding S DIE in 30/338 with 8 mm bushing , by this way you get a cartridge wich is very close to the 338 WIN and Nosler Partition are very good in 8 mm ( I use a 8 REM MAG with Partition on SAKO action ).

I think the original cartridge is 323 Olis but not sure .

good shooting

DAN TEC

It is a very common practice here in Europe, to build 8x68S's around Mauser 98 actions.
Magazine and receiver lips will most probably require some modifications, as they will require every time they are screwed a barrel for a caliber different than the original.
Go ahead and enjoy your project.
montero

WildCat I'm with Dantec on this. I think the barrel diameter around the chamber area of the K98K barrel is too small. Also those K98K barrels are 23.6" long. you won't be able to get the full benefit from the 8x68. What is the manufactures code & YEAR on top of the receiver BYF,BNZ,BCD,CE,
AX,DUV,127,147,ETC?

Dear Montero

there is Europe some bad folk to built any caliber on any action .At the last IWA show( since sevral year now ) you can see one 375 HH built by a well know gunsmith in Lieges in 375 HH on soft 1909 Mauser action !!!

the basic and false idea is

action are hard to find ? several year ago perhaps now you get plenty on a phone call .

the gun sucess to pass the proof house so the gun works OK BUT :

FOR HOW MUCH TIME ? and HOW MANY ROUND BEFORE SMASH the receiver lugs ( set back )

I have even see a 378 WEA built on M98 action with amazing cut in the receiver sure that proof house is OK but I doesn't want to shoot the rifle ?

for few hundred $ or Euro you can purchase a brand new long action BRNO so why spend time and money to modified safe M98 in unsafe M98 just to shoot big cartridge

all big classic cartridges even the 500 Jeffery on M98 are low or very low pressure so OK for M98 heavy altered .

If some guy sucess to find brand new shape action M98 with matching number why not

Built a more reasonable caliber

sale the barreled action ( a good price ) and purchase a BRNO 550 mag and save time and get safety thing.

never forget that built a complete rifle is money and swicht the receiver or make a mistake in receiver choice is a nightmare .

Good shooting

DAN TEC

Wildcat, take some measurements on the chamber area of your barrel. If it is indeed 1.1", that should be lot's of metal. The 8 X 68S case is only .524" at it's widest, so you're still left with .576" or .288" wall thickness. Up at the shoulder the case is .478", so meausre at both areas. If you take most of your magazine opening from the rear, and just touch the feed ramps, I don't see any reason this won't work. Hornady gives a maximum col as 3.425", and I have an 8mm-06 AI that goes 3.4" with no trouble, so I don't see this as a major problem. As long as the measurements pan out, I would go ahead. As a matter of fact, I'm on the lookout for a decent 98 8mm to do the same thing to. Good luck and have fun. - Dan

Wildcat,a friend of mine once owned a 8x68S on an original M98 barelled action, the first 8x68S I've ever seen,so it is very well possible,but: he sold it quite soon because it kicked him sooo hard every time he pulled the trigger.Apart of this:the 8x68S is a good potent caliber,expencive yes,I guess you should reasure you about the price of the brass you mensionned,are you sure it is for 100 not for 20?Anyway, you need quite a long barrel to use the full potention of the 8x68S.
Hugh.

The action in question has an Eagle/Swastika on the top of the reciever with 42 stamped @ the rear. There is another Eagle/Swastika on the side with a seriel # and the letter "c". The fit and finish are supurb for a milsurp with the reddish blue finish still on the bolt body similar to what I have seen on commercial Mauser actions. The action has no slop and is very smooth. Every piece has matching #s. The stock however is a "cut down" sraight grip model that originally had a "top tang" on the butt plate. (it now wears a poorly fit recoil pad) this is not the original stock, perhaps it was from a M98 Gewere? I have a Fajen drop in stock that I have had since the late 60s. I will probably use it for this one. Other than the rechambering and feed rail work, I will be doing everthing myself. I have a bolt welding fixture and I have 3 actions (2 are comercial "large ring intermediate" length Yugos) to convert to 3 pos M70 type safeties so I will buy the fixture for that also. This will not cost me much (the barreled action was free! All I am really risking (if this conversion is deemed safe by a general consensus of opinion both proffessional and other wise) is a really cherry issue barrel (I do have another one )and $80.00 plus shipping to rechamber. $50.00 for cases and another $60.00 for a set of Redding dies from Sinclair. If, after shooting it, I like it, I will probably spring for a realy nice semi inletted classic style stock as I did for my 8mm-06 Imp. If I don't, I can yank the barrel and do something else. I am sure I can sell the dies, perhaps the brass too. The bolt face will only be opened to .512" so I could always rebarrel for something else. Perhaps an ultra mag case shortened to 2.5" in 8mm. Or one of those damnable belted monstrousities. (I would use a new barrel for something like that.)

Barrel diameter @ the shoulder area is .950" leaving a chamber wall thickness of .234". The shoulder diameter is only .019" larger than my 8mm-06 Ackley Improved. Chamber wall thickness is .0085" less than the 8mm-06 Imp. Would .0085" make that much difference?

Load data I have reviewed put pressure @ 55,000 PSI. (50,000 for factory loads) I think that level would be safe in the issue barrel. (there is not a spot of rust on it) I talked to a reputable gunsmith about it and he did not seem to be concerned. I will research this factor further! I may indeed rebarrel, I am not at all concerned about action modifications as this round was designed for the M98 action I believe. It is not nearly as long as the H&H Magnum derivatives. (about .200" shorter)I have already done an 8mm-06 Ackley Improved on a M98, this won't require much more as far as action mods. I was able to get 3.375" magazine length without extending the front of the mag well. It wouldn't be hard to get another .125" by extending the front of the mag well and some file (German Mill?) and dremel work on the feed ramp. I will leave the rails to the "professional" gunsmith.

I have no use for a belt on a cartridge case other than a 375 H&H, so the various belted magnum wildcats are not my cup of tea. Besides, the shoulder diameter of the 7mm Rem and 338 Win mags is .491"! That is .028" larger than the 8X68S! Now we are reducing chamber wall thicness to .220".


As far as kicking, good stock geometry and a 1" "Decelerater" pad will help. I don't plan on wiping out a colony of Ground Squirrels with an 8X68! Besides I could always "load down" if I did want to wipe em out the pesky litte critters with an 8X68! This will probably be the "biggest" gun I will ever own, and indeed will be "bigger" than I really need! I live just across the border from Quebec, and if I ever go Moose hunting (or Elk, of Grizzley etc. etc.) the 8X68S should be able to get the job done handily. Actually my 8mm-06 Improved would too, but you know what they say about power "It's better to have it and not need it than to need it and not have it"! Beside, the main purpose of a gun is to please the owner

Brass price is $9.05 per 20. ($45.25 per hundred) This is for Hirtenberger brass, RWS is $37.14 per20. I will call Old Western Scrounger to confirm these prices and the quality of the Hertenberger Brass. I have found Hertenbergers website, it is impressive. (it's in German) They list a 200gr Nosler Partition @ 2936fps. Even in a 23 3/4" barrel I should be able to get nearly 2900fps. I think these loads are @ 50,000PSI.

[ 08-15-2002, 22:16: Message edited by: wildcat junkie ]

You can probably sell that barreled action to a collector on the k98k page for $500.00.

dear dantec:
maney is normally not the issue whenever a custom or wildcat project is started.
from a strictly practical point of wiew we would al be shooting rem-chester thirty o' sixes or whatever.
and let me insist that it can be done, and that it can be done safely.
waffen frankonia, luger, zastava, auguste francotte, mahillon, the dumoulin's, etc. etc simply cannot be all wrong. and I have seen 98's from them in 8x68S.
argueing with success does not seem like a sensible thing to do.
we are not talking 378 weatherbys or 505 jefferies here.
rebatds,
montero.

Dear Montero

perhaps but for your knowledge on this problem :

this is not because it is a BIG NAME of the European Gunsmithing engraved on :
that contrain to be very good

I don't think so

you are welcome at the next IWA show and I take my portable hardness tester ( aero space industry equipement ) , I am sure you will be happy by the result of hardness testing on some great name rifles built on M98 action ( not all I agree ) and detail of the quality of workmanship ( not all I agree too )
Some rifles are design and built just to be pretty on catalog picture or on show table no to be reliable and safe after thousands rounds.

Never forget that in Europe Hunting rifles are rifle which shoot low number of rounds during the hunter life because only few hunters make practice and shoot a lot .

good shooting and Enjoy engineering and mecanical facts rather trade mark engraving .

DAN TEC

Okay here are some facts:

The Hirtinberger 8X68S brass is indeed $9.05 per 20, $45.20 per hundred. It is reputed to of good Quality. I have ordered 20 and will base my decision on the quality of the brass. If it is not up to snuff I may abandon the Idea as I will not want to pay RWS prices.

I extended the magazine for my 8mm-06 A. I. to 3.520" inside length. ( I will use "bumpers to keep the 8mm-06 cases to the rear) It will just fit into the stock inletting, and I will have to take about .125" off of the feed ramp. I can do the same with the 8X68S magazine and have ample room for COL of 3.45" with room to "grow" if I ever shot it enough to erode the throat. Not a problem there.

The taper of the 8X68S case is almost identicle to 7X57 cases. IMO it should feed like "greased sausages" with minimul feed rail work. In any case it will probably require less tinkering than a 8mm/338.

The wall thickness of .236" @ the shoulder area will be more than adequite per the opinions of two highly regarded gunsmiths, one of them a barrel maker. Again it will give a great deal more wall thickness than a 338 Win Mag based Wildcat.

Most data for factory loads or reloads give 2936fps to 3030 fps for a 200gr and 196gr bullets respectively in a 26" barrel @ 50,000psi for the former, 55,115psi for the later. This is midway between 30-06 and 270 factory load pressures for the faster load, and way below 338 Win Mag. These are with Col of just @ 3.4" or so. Loading to 3.45" COL should reduce pressure further IMO to allow nearly the same performance in the 23.6" military barrel @ acceptable pressure levels. Again below 338 Win Mag specs. I would think that 2950fps with a 200gr Nosler Partition would be realistic in the 23.6" barrel, perhaps slightly more. 3150fps with 180gr Ballistics Tips might be doable.

I am leaving the barrel close to original contour with only removal of the rear sight and tapering the sight flat into the chamber area, and then blending the chamber area in @ 15deg. the barrel will still have some heft, and if the recoil is still a bit much with the walnut Fajen stock that I have, I can add some weight to the forend with a brass rod inset into the wood from the inside. I think I should glass in a few "harware store crossbolts" from the inside per Jack Lott's method. I think it would be realistic to get a 9# rifle with scope attatched.

I ran across a Williams "Foolproof" aperature sight for $25 NIB the other day. I already have several "Mark II" safeties and a Fajen stock. I perchased a Timney "Sportsman" trigger for $29.99. Add $50 for 100 cases, $60 for Redding Dies from Sinclair Int. and $80 for a rechambering job. Throw in $20 for shipping, and I have a real rompin stompin "Bear stopper" for less than $250, including dies and brass. I can add provisions for scope mounting later.

This is going to happen as soon as I finish my current project. I think this will be a "no muss, no fuss" conversion. Everything else (The Vz500 actions)will have to go to the "back burner"! I should have it going before hunting season. Can't wait to feel the recoil!

I sure hope those Hirtinberger cases are dandies!

[ 08-20-2002, 16:13: Message edited by: wildcat junkie ]

dantec In your first post you stated the 8x68 was very hard to reload! Would you care to explain what the problem is?? I have only been loading the 8x68 for 7or 8 years and I always thought it was a dream to load. No stupid belt, that RWS brass is some of the best anywhere.

I have an 8x68S on a Global Trading M98 action that has turned into my favorite rifle. I load Partitions, Speers and X-bullets all 200 grn at OCL of 3.390. They all perform and function very well. I use the inexpensive brass and have had very few problems with it. I do recommend shooting a light load in the first firing, for some reason it has saved some cracking along the necks I had experienced on a few cases. You have to be alittle creative to come up with a load for the 200's but its not to difficult. Recoil is very managable. Come on in the water is fine!

Dan Tech---

The "soft" pre-1924 Mausers, primarily from DWM in three contracts, were case hardened selectively. The lug recesses were double treated, the inside rails and feed ramp, lug races. etc were single pack hardened.

THAT'S why good custom rifle builders use them. They're easy to weld on because there is no added carbon to cause pits. They are an absolute delight to engrave and inlay work is much easier.

Some of the finest rifles in the world are built on good Mausers.....because there has never been a better foundation for a hunting rifle made. Everything after the 1935 M-98 was only made cheaper....NEVER better.

I have built ten or twelve 8x68s rifles on M98 actions, all with the military barrels that came on them. These ranged from the 1917 series to later dates. The barrels never were an issue, although I had two 1917's that suffered from the lugs setting back after a few boxes of ammo had been sent downrange. An excellent cartridge!

Hola Wildcat
The HP cases it's not the best ones , research on reloading forum for soft brass or Hirtenberger , very soft , you can buy RWS directly from Germany , or try ebay.de for used cases .
Saludos

Daniel

Does anyone have pictures or case dimensions of the 8x68s? Does it use a magnum or a standard bolt face?

The original action for which the 8x68S was designed was the 98. So it will fit for sure. The case has lots of capacity. There should not be too much rail work, but opening up the bolt face as discussed and spreading the mag box for capacity.

If you ream the chamber, using the original barrel, this will be a quicker twist than designed. Don�t use weak ( = standard ) bullets under 200 grs weight. The longer 8x68S twist was made because the lightweight H Mantel bullet desintegrated with this strong cartridge at trials.

Still, a quick twist seems favourable for penetration. It would be really interesting to check penetration of a 1:9.5 barrel, 8x68S and 250 grs Woodleigh solids ...

Otherwise use 220 grs A Frame.

If you run in any trouble with the Hirtenberg brass, it might be tight flash holes. Grind down the pin or use a hammer type decapper for .223 and be happy...

Theoretically the issue barrel will be more slender forward. I�m not sure if this will be a problem with even the slowest powders.

Hermann

P.S.: the 8x68s is no sweetheart, no standard loads, etc, but its a terrific cartridge! If you are forced to use factory ammo give Blasers CDP a try!

8x68S case are very costly and very hard to reload .

I shoot 8x68S in Germany. It is the better 8mmremmag because it does not have a belt. It is not hard to reload, but RCBS dies in this caliber are produced not very precisly... So i had to short the shellholder...
I would prefer the Blaser CDP bullet with 196gr.

I received the Hirtenberger brass the day before yesterday. It looks to be fine to me. I weighed them and extreme spread was 2.8grs. (Less than 1%, 300grs was about average) 15 of 20 were within 1 1/2grs. (1/2% variance) The necks have been annealed as evidenced by the discoloration of the brass. The case mouths look better than anything I have ever seen from american manufacturers. I think I will get 20 RWS cases just for comparison. Loading both brands until I see some signs of failure such as loose pockets etc. will give me some idea as to whether or not the RWS is worth nearly 4 times the cost.

I will be ordering Redding dies from Sinclair Internatioinal. They run $60 and change. Does anyone have experience with Redding dies?

Just for the hell of it I shoved 3 cases into the magazine of the 98K I am going to convert. I "short stroked" the action and the top 2 rounds would actually be picked up by the unmodified bolt. The last round would hang on the feed ramp. The case mouth would catch. Once the magazine is lengthened to about 3.60", the bolt face and extrator opened up and bullets are seated to about 3.550" COL, it wouldn't surprize me if the action would feed flawlessly without further modifications. The taper on the 8X68S case is almost identical to 7X57. I had an extra trigger gaurd lying around so I campared the way the 8X68S cases lay in the box compared to 8X57. Although the box would only allow three 8X68S cases to fit, they were @ the same angle in relation to the top of the box as the 8X57 cases, with more clearace than five 8X57 cases. I will modify (bevel and polish) the face of the extractor (as I always do) to allow the extractor to "snap" over the case rim of a round already in the chamber. This will allow the rifle to be carried with 4 rounds loaded. If I can't "get the job done" with four of these babies I'm not doing something right!

I am leaving the contour of the issue barrel "as is" except for continueing the tapered portion ahead of the flat section where the issue sights are soldered on back to the chamber step. It will just clean up when the chamber step is reached. A taper angle increase to 15 deg. will then blend the transition with the chamber area in nicely. I am not concerned about the barrel being stiff enough in this configuration. Ater all, isn't that what the "steps" are all about? A stiifer barrel for a given weight? Were the "steps" the 1898 version of "fluting"?

After looking at the 8X68S cases, I don't understand why this case has not been the basis for more "wildcatting". More attention would probably result in somebody like Hornady producing cases. Look at the 6.5/284 for example. The 284 Winchester was pretty much "dead in the water" until recent interest in wildcatting it. Now Hornady produces 6.5/284 cases.

When I look at the 8X68S case, it screams "Ackley Improve me" to me! Minimizing case the taper and "blowing the shoulder out" to 40 deg. would make a real stomper out of this one! Perhaps it would supass the 8mm Rem Mag.and its various derivatives. How about a 7X68S Ackley Improved, or a 338X68S Ackley Improved, or a 358X68S Ackley Improved or a 375X68S Ackley Improved or for that matter an 8X68S Ackley Improved? Hmmmmmm.

I gotta get my other "projects" wrapped up so I can get on this one.

[ 08-30-2002, 17:57: Message edited by: wildcat junkie ]

Man WJ, you're just full of interesting ideas today. Some of these old cases are really interesting in improved versions. Another one I would like to try is an Acley Improved 280 Ross. A whole family of 68 based improved cartridges, what a great idea. I only have a couple of sets of Redding dies, no problems with them. My 8 X 68s dies are RCBS. Oh, I expect my buddy Mark back the first weekend in September (I talked to his wife yesterday), and I'll let you know about that barrel (I know he wants it, I'm just not sure what kind of horsetrading he's willing to do). Take car - Dan

WJ, Some fine ideas there bud. I used to buy RCBS dies but after I was introduced to Redding dies back in 1980 I have bought no other & I have bought a lot of dies.

Hello Wildcat Junkie

Here is a copy from a post from a German fellow enthusiast (L Moeller) re the 8x68 that speaks for itself.


"It’s great Cartridge, very strong, withstands the most Pressure from any Cartridges I know. Around 5.000 bar are handled well with Primers still stuck. I notices the 9,3x64 Brenneke, if blown out to with larger frontal Diameter in a specially reamed Chamber, holds about the same 5g Powder, as the 8x68S, but above about 4.500 bar pops Primers."

My experience bears out his statement - a load that completely flattened the primer - like there was no radius on the corner of the primer whatsoever, there was a shiny spot at the ejector groove that you could feel with your finger nail, every machining detail on the bolthead impressed into the back of the primer and case, the brass flowed up the chamber so that I had to trim over a millimeter to return it to standard length, a load that left the imprint of 5 shots on my shoulder in the form of broken capillary vessels ..... the primers remained tight in the pockets.

How I wish that I had chronographed those loads.

Certainly the pressure exceeded the yield strength of the brass by a handsome margin.

No need to wildcat that cartridge.

Those RWS cases have been reloaded 5/6 times so far - only the one trimming and one annealing needed so far. Admittedly I've reduced the loads slightly.

cheers edi

[QUOTE]Originally posted by edi malinaric:
[QB]Hello Wildcat Junkie

Here is a copy from a post from a German fellow enthusiast (L Moeller) re the 8x68 that speaks for itself.


For all who are interested in 8x68S!:
http://home.snafu.de/l.moeller/