The Accurate Reloading Forums THE ACCURATE RELOADING.COM FORUMS Rifles Medium Bore Rifles Re: 8mm options?Go | New | Find | Notify | Tools | Reply | |
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| one of us |
Quote: Bro, I don't mean to give you too hard of a time, but this makes no sense at all. If you start out with a smaller case in the first place you're already compromising powder. I'm sure you're happy with your choice, and the 8x60 S is a great round, no doubt, but the 8mm-06 will beat it every time - if only by a little, and the difference increases as bullet weight decreases - and the cases are EVERYWHERE. Starting from scratch I would advise toward the '06 case. | ||
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| one of us |
Yes, other than a possible "masochistic" fun or "be different" factor, I don't see the point either in starting out with some exotic case. Heck, '06 cases are everywhere. Even the 64mm cases are not nearly as proliferate in the States as they are in (Central) Europe. Why make life harder than it has to be?? - mike | |||
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one of us |
Let's assume that we are working with a sound action with a good to excelent bore of .323 cal. The 8X57 if loaded to modern pressure levels (say just under 60,000psi) will give you about 2,800fps with a Nosler 180gr Ballistic Tip, 2,600 with a 200gr Partition. Going to an 8mm-06 will get you another 100fps An 8mm-06 Ackley will get another 100fps over the standard 8mm-06,(3,000fps with 180grs 2,800 with 200s) but more importantly it will increase the life of the brass and reduce bolt thrust. I have loaded Norma Brass 12-14 times @ 3,000fps with 180gr Ballistic Tips. Case failure was ussualy due to neck splitting, although primer pockets where getting a little loose by then. No sign whatsoever of case head seperation. The 8mm-06 or 8mm-06 A.I. will require a ream job. some work with a file to open up the magazine to 3.38" and some work on the feed rails. The Ackley version will require a little more work to feed properly. Expect another 150-200fps across the board for the 8x68S over the 8mm-06 Ackley. This choice (8x68S) however will require some mojor surery to the magazine box, bolt face and feed ramp. As mentioned the 8x60 or 8x64 would hardly be worth it in the U.S.A. as "06" brass is vastly easier to come by and factory loaded ammo in the 8x60 or 8x64 is limited in choices and availability. Although the 8x68S has limited availability, it would be worth it in my opinion as the performance level is right there with the 8mm Rem mag or 338 Win mag in a shorter OAL than the Remington without the worse than useless belt of either. | |||
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| one of us |
The Swede Nils Kvale constructed a chambering called 8mm Kvale. AKA "poor mans magnum". It was based on a shortend 300H&H case. It's main purpose was to offer magnum speeds out of all surplus 8mm Mausers! Later the 8mm Kvale was the base for the 308NormaMagnum and 358NormaMagnum cartridges. | |||
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| one of us |
GBF, Mic the 9.3x64 case diameter and compare it to the '06, or do H2O volume comparason. You will see a significant difference. VFR | |||
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| one of us |
Quote: But the 8x64 Brenneke and 7x64 Brenneke don't have the same fat case as the 9.3x64 Brenneke! | |||
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If you aren�t satisfied with the 8x57IS, go with a 8-06AI, as the other alternatives offer hardly any value for the job and the money. (Nonetheless I�m the owner of a Mannlicher 1950 8x60S Magn.) Another alternatives, which require som job on the bolt face are the 8x68S (magasine length too) and the spanish wildcat 8x64 S Mazon. The latter is a 9,3x64 narrowed to 8 mm. The 9,3x64 has a fatter case than the 7x64 or the 8x64S. In fact it�s mostly identical to a 64 mm belted mag case without belt. Here is a picture of 8mm MAZON flanked by 7,65R and 30'06:  More about the 8 mm Mazon at http://home.snafu.de/l.moeller/8-9,3x64S-Brenneke-Mazon.htm Scroll a bit down as the top of the side is German, but the rest in English. Best regards, Fritz | |||
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one of us |
The 8x68S is the best choice for max power, reasonable ability to get brass, and the magazine length in the 98 Mauser. Old Westeren Scrounger has the brass and it is around 1.50 to 2.00 each in box of 20's. However, I have also found it on ebay and auction arms. In a pinch you can make brass from 6.5x68 using a tapered expander in three or four steps. Clearly, the 8x68S is everything and more than the 300 Win Mag. The disadvantage is simply it isn't as common here in the USA, although there are a lot of wildcats based on it here. Quite a common caliber in Europe, I understand. RWS makes the brass. Loading data is available in the A-Square manual and others. Another good option that has almost as much power as the 8x68S is the 8mm Hawk. This is a wildcat with correct empty brass available for it. Created by Fred Zeglin as part of a larger line of HAWK cartridges. See www.z-hat.com for more info. This is based on a 30-06 case and has more capacity than a 8mm/06. Fred has loading data, dies, and cases available at his website. His data is pretty conservative, however. I can attest Fred's quality, as he built two rifles for me and is working on two others for me now. My advice, unless you simply want something different, is get an 8mm cartridge that gives you at least 200 fps and preferably 300 fps difference in velocity to justify the change. A wildcat, such as a neck expanded 300 Win Mag to 8mm is a good easy wildcat to make and I know someone out there had to have made this one already. This means the reamer is out there, along with the dies. Fred has a 8mm/338 Win Mag reamer in house; check out his list of 8mm reamers. Cost - Consider this: If factory brass and dies are available, but in hard to find calibers, a wildcat isn't so expensive. Assume 8x68S brass at ~$1.75 each, dies at $75 to $100 since they are special order. If you buy 200 cases and the dies, it isn't too much more to simply build a new custom wildcat on the dirt cheap 300 Win Mag case. If you can find a reamer for it, it could be cheaper! Wildcats exist for many reasons, simply doing something new isn't always one of them. RobertD | |||
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Well, I was referring to the 7x64/8x64 cartridges. They are close to being equal to the 06 in volume. Regards | |||
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| one of us |
I second what Wildcat Junkie said about the 8mm-06 AI (how you doing WJ?). Also, there is the 8mm Gibbs, which is about as much capacity you can get out of the -06 case, and will equal the 8 X 68S in velocity. The 8 X 68S AI is another choice (and one I'm really anxious to try), which should put you right on the heels of the 8mm Rem Mag, and still fit in the 98 action. - Dan | |||
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| one of us |
It sounds like you're not so interested in machine work to get this thing to feed. I would suggest you get in touch with a smith you like, and find out the $ difference in a straight rechamber vs full conversion to another case size (rail/boltface work, etc.) You may be surprised at the difference. Then again, you may be surprised at what sort of loads you can work up in the original chamber. If you're just trying to get more power out of a 98 w/o much money, easiest thing is to handload. If you want a sporty hunter, don't kid yourself into thinking you'll rechamber and leave the rest alone. Go somewhere dark and quiet and come up with the biggest dollar amount you can bare to let go of. | |||
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The reason I'm concerned with magazine and bolt face modifications is that I asked the question mostly for a friend, who wants to do as much of the work himself as he can. I'm pretty interested in 8mm rifles too, but I don't really have the money to do much of anything right now. | |||
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| one of us |
The 8mm-06 and the Ackley Improved version will not require a lot of modification that can not be done by the "ametuer" gunsmith other than the reaming of the chamber and some feed rail work. The bolt face will not need to be altered. It is relatively simple to open up the magazine to 3.8" with nothing more than a good mill file. The standard K98 (standard length) magazine measures about 3.31" The rear wall is about .120" thick, and this can be reduced by .060" giving an I.D. of 3.37" A little material may or may not need to be removed from the bolt stop with a Dremel Tool to allow the bolt to come far enough to the rear to pick up the rim of the cartridge. Another .010" to .015" can be filed from the front to get 3.385" ID. This will allow a COL of 3.34" 3.35" with a little "breathing room". If you are going to have a "professional" do the reaming, I would suggest that you also have the feed rails done @ that time. Harry McGowen of McGowen Rifle barrels did the chamber and feed rails on my 8mm-06 Ackley, and I was very pleased with the work. When reaming an Ackley Improved chamber, the shoulder should be "set back" to simplify fire forming and allow the "standard" (8mm-06 in this case) cartridge to headspace on the "standard" case shoulder. The 8mm-06 Ackley Improved was my first attempt @ having an 8x57 "rechambered", as well as my first reloading attempt other than shotshells. The 8mm-06 Ackley will give the same level of performance as the 300 Win Mag with 180gr Bullets, perhaps a little better with 200grs, definately superior with the heavier .323 bullet weights of 220 to 250grs. The 8x68S however is a "whole nuther ball of wax" It will require the bolt face to be "opened up" to accept the .509" rim and the magazine will need to be lengthened to 3.5" to 3.6" (about the practical limit for a K98) as well as the feed ramp to get the most out of this cartridge that has a COL of 3.425" I don't believe that the feed rails will need to be modified though as the case taper is almost identical to the 7x57 case. I can get the first 2 empty cases to feed through an unaltered K98 action. The last one will hang up on the case mouth, but after all these are empties and the bolt face is not even big enough. The extractor will still pick up the .509" rebated rim though. | |||
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If what you're saying about the 8mm-06 AI is true, I WANT one! It seems like quite a step up in performance from standard .30-06 loads. | |||
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| one of us |
Quote: There is nothing "magic" about this cartridge, (8mm-06 A. I.) just some basic physics @ work. When compared to a .308 bullet, the .323 cal bore allows more surface area @ the base of the bullet to respond and react to pressure along with a larger expansion area within the bore. A 180gr boattail .323 bullet however will not have the same Ballistic Coefecient (BC)of a .308 boattail bullet of similar contruction. The trade off is that the 180gr .308 bullet will shoot slightly flatter than the .323 bullet of similar mass. That is the trade off. However, a 300 Win mag has a hard time using 180gr bullets with a high BC as the longer sleeker bullets start to infringe on powder space within the longer case. The OAL of the 300 Win mag will be the same as the 8m-06 A.I. (3.34")if you lenghthen the magazine as I described. However, a .338 bullet of similar consruction will also not have as high a ballistic coefecient as a .323 bullet of similar mass. So----- you get the picture. When one increases the bore diameter of a given case design the cartridge tends to become more effeciant with a heavier bullet. An 8mm-06 (or the A.I. version)would not be very effecient with bullets of say 150-165grs. Here the 30-06 would be a better choice. Also, a 338-06 would not be as efficent with a 180gr bullet as the 8mm-06. The 338-06 works better with bullets over 200grs. Going the other way, the 270Win is much bettter when using bullets of 130-140grs. But, here's the beauty of the 8mm bore when using a case with the same or similar volume as the 30-06 (8x60, 8x64 etc) The cartridge really shines with bullet weights of 180-200grs. The .323 180gr Ballistic Tip is devastating on Whitetails. A little heavy for Antelope or small southern Whitetails perhaps, but ideal for big northern Whitetails. Elk, Moose etc. would be better suited to the 200gr Partition. Would I chamber a new barrel in 8mm-06 or the A.I. version? Probably not, then I would opt for an 8x68S or perhaps an "improved" version. The point is, if you have a good sound 8x57 Mauser that has a very good bore, there is no sense trashing the barrel if all you want is a hard hitting reasonably flat shooting hunting rifle for medium to large North American game. Of course the 8x57 when loaded to similar pressure would suffice, the 8mm-06 A.I. will just do it a little farther with more authority. The issue barrel will probably not shoot 1/2" groups, but it will probably shoot groups under 1 1/2" @ 100yds. Sighted in 2 1/2" high @ 100yds ( with a scope mounted to have the line of sight 1 1/2" above the bore axis) the 8mm 180gr Ballistic Tip bullet @ 3,000fps will be 3" high @ 150yds and about 3" low @ 290yds. The 200gr Partition won't be far behind because of the higher BC. | |||
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one of us |
How about an 8 x62 (9.3X 62 necked down)? Should have about as much case capacity as a 8-06AI. It would be very similar to 8mm Hawk--or what ever it's called. | |||
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| one of us |
It's interesting to see all of the reasons that the 8mm is shunned in the U.S. The only real reason is the supposed lack of bullet choices. Now granted you might not be able to get exactly what you want. I would dearly love to see an 8mm 200gr Hornady Interbond. These are awesome bullets. I shot a huge Whitetail doe with a 7mm 139gr quartering on @ 30yds. The bullet was traveling @ something slightly less than 3,100fps on impact (about 3,140fps MV) After entering high just behind the scapula, the bullet was found in the off side hind quarter under the skin next to the femur. Weight retention was 85% with expansion to .782" The base was concave from the bonded lead core trying to pull out! Could you imagine a 200gr 8mm Interbond @ 3,000fps MV from an 8X68S? Anyway, there are bullets available in .323 from the 125gr spitzer,(Speer I think) to 250gr solids, with all the Swift "A" frames, Nosler Partitions and Ballistic Tips, hornadys, Sierras, etc, etc. Heck there are even several molds available to make lead bullets with gas checks. And that's only what's available from U.S. manufacturers. The Europeans have even more variaty. Why are Americans so afraid of metrics? It is a much better system. My ideal all metric North American battery (aside from a 22 rimfire)would be thus.
I think that would cover just about everthing that walks or crawls on this side of the pond, with plenty of "overlap" to boot! | |||
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| one of us |
Quote: Not reasonable. The ever so slightly fatter case of the 9,3x62 - the dimensional differences are hardly discernible - does not offer any real advantage over the lengthened M/88 case (such as in the factory rounds 8x60 and 8x64). The Italians used a fatter case for their fine 8x59 RB Breda. Regards, Carcano | |||
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Since you are wanting as little modification as possible then the 8mm/06 is the best route and has been for many years... It only requires a rechamber and its one heck of a hammer on big game....all the rest require extensive changes...Also brass is very available and bullet integrity is by far better than the hotter rounds as most 8mm bullets are designed for slower velocity...I suggest the 200 gr. Nosler....Its an easy keeper.... | |||
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Quote: Wrong. Quote: Clearly wrong as to the second statement; and the first is equally true for the two other choices. Carcano | |||
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One of Us |
Quote: The 8mm Hawk is virtually the same thing as the 9.3X62 necked down. It is also nearly identical to the earlier 8mm Gibbs only with a lot more hoopla, and they will both give a bit more than the 8mm06AI but arent nearly as easy to form cases for. | |||
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| <JOHAN> |
Quote: Aha  Tell us more about this cartridge. Pictures and plenty of information would be nice  Don't be shy / JOHAN | ||
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| one of us |
Quote:Quote:  Actually as far as I know, this cartridge does not exist other than in my fertile (horse manure?) imagination.If you like, I could run a "Quickload" on this hypothetical wildcat. | |||
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Okay Johan here it is. Quickload data for 9.3x68S wildcat 250gr Nosler Ballistic Tip 33.425 COL 24" barrel 63,000psi max pressure
Incremental data for VV N550
Maximum point blank range, + or - 3" @ 2628fps MV [list] Sounds like a real "thumper" to me. With the right bullets, this ought to be able to handle anything that walks or crawls the face of the Earth let alone the North American Continent | |||
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30gibbs: Rather than go through this again, I'm giving this a "boot" for you. | |||
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| new member |
Thanks for the boot!! I think I am leaning to 8-06 AI.The barrel on the gun is in good shape, I will just have it reamed. I reload all the time for my 30 Gibbs so 06 brass is always handy.Will I have to do much for the feeding or magazine?? | |||
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