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Discussion Starter · #1 ·
I have a Gew88 that I've been shooting for several months with Yugoslavian surplus 8mm. The other day, a guy told me that this is very bad for the rifle and could eventually cause it to blow up. I don't believe him because I've put over 200 rounds of it through the rifle with no problems. No split cases. Nothing. Is there anything out there that backs up his claim?
 

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Gew88 and Yugo surplus 7,9mm ammo.

First thing...your Gew88 is at least 110 years old, if not older ( production dates, 1889-1897).
Secondly, the barrels were originally made to use a .318 round nose projectile in a .321 Groove barrel
(so called "7,9x57 J");

In 1905, the Germans upgraded to a Pointed bullet of .323 diameter (7,9x57 JS), for the Gew98 (new rifle).

The older Gew88s were then "upgraded" to use the new diameter ammo, by relieving the throat of the rifling to better engage (and swage) the new bullet. Most (but not all) Gew88s received this "s" conversion, and are so marked on the receiver and/or barrel.
This "s" conversion was suitable only for the original 154grain "S" bullet, with a very small groove bearing surface...the Boat tail 198grainer of WW II and later is definitely too long and heavy for use in a Gew88. (pressure risks)

Yugo Milsurp is at the upper limit of pressures for 7,9mm Military ammo, and its age (most Yugo is 1950s-1970s ), is designed for use in "S" type rifles (.323 grooves, M98 type three lug bolt.) The 198 grain Yugo bullet is meant for Kar98k and Yugo M48 type rifles.

The fact that you may have fired some 200 rounds through it means nothing...it will eventually give way, either by cracking the bolt lugs, bulging the chamber, bursting a barrel (common occurence with even the early "J" ammo); Even a simple case failure will send debris and bits of bolt back into your face.


If you want to shoot your Gew88 safely (for the next xx years,), Use either US Commercial "8mm" Loads ( lowpowered and undersized bullets), or handload your own with either case lead bullets (the safest way) or reduced load jacketed bullets ( say 75% powder charge.) by either using new components, or dismantling the Yugo ammo, and re-measuring the Powder charge.

Regards, Doc AV
AV Ballistics
 

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Well said, Doc. Very sage advice.
 

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Doc, great as usual!

May I ask a favor from you? The nature of the "S" conversions in Gew 88 and in Mannlicher M.95 is deeply misunderstood. Would you write a short, but comprehensive exposé on the subject and I will make it "sticky"? Please?
 

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Now, normally i think most people panic too much with these ammo types, however, Doc sounds like he made a very logical point because bullet weights are going to affect pressure as well. Garands can't handle heavy bullets cause they'll bend the op rod. PPU sells 8x57 J bore ammo for this rifle specifically, and you may be able to find it somewhere in this country.
 

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Discussion Starter · #6 · (Edited)
Good points. Thanks for the advice. Will the 8mm J bore ammo work effectively in my year 1897 S-marked rifle? I hope I don't seem like an idiot...I'm relatively new to shooting old military rifles.
 

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You need to slug your bore. If your rifle is a 1897 and has the original German barrel on it, the groove will be .323+ [ most are .325 ] . If you shoot .318 dia bullets in a .325 groove bore you will have poor accuracy. You would need to reload with a mild [ about 2400 fps or less with a 150 grain bullet ] load and a .323 dia bullet. As said before, the rifle is OLD. Your rifle could have a Turk barrel on it, or a Czech .318- barrel . You need to find out what you have and use the correct ammo for what you have. If you do not reload, And HAVE a .323+ groove, the Romanian surplus with the .3215 dia, 154 grain bullet at about 2500 fps would be safe, but maybe not that accurate if your bore is big. mag
 

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TO Moderator Nick re: "S" conversions

Will attempt it in next few weeks...I am presently briefed to defend an old man on a charge of Gun Trafficking (here in Aust. a 20 year offence), so I will be fully engaged in legal work...will try to fit it in as a "stress reliever">

Thanks for the request,
Doc AV
AV Ballistics.
 

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While Doc's right, some Gew88 have .323 replacement barrels that don't just gradually squeeze a bullet down to .318, and are slightly safer shooting modern-dimensioned 8mm ammo, there's another big risk- Gew88s have no gas venting.

If you blow a casehead, which is more likely due to increased pressure if you're shooting oversized bullets through a tight bore, there's not going to be a carefully redirected venting of the red-hot propellant and metal splinters through cutouts in the bolt and reciever like in a '98 Mauser. Bad Things can happen.

The combination of bore sizes and bad venting means people can stack both risks at once and have Really Bad Things happen.

That said, there's quite a few people that shoot their Commissiongewehrs- AFTER they have slugged their bores and know what's safe!

If you have a sub-.323 bore use either bore-appropriate handloads, OWS or other commercial I bore ammo, or MAYBE commercial Winchester or Remington underloaded and undersized 8mm ammo.

People with .323 rebarreled rifles often shoot the commercial Win/Rem (don't shoot Euro stuff, it's much hotter!), downloaded surplus ammo, and there are even a few hearty souls who've put Romanian surplus downrange through a Turk 88/14/35 rework.

The Gew88 is a great gun. But it's so old you really need to know and understand the rifle completely before you take it out and enjoy it, and you should always err on the side of caution. The Gew88 and the Ross are probably responsible for more "that old army gun done blew up in his face" stories than anything else.
 

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Since the original German barrels did not have .318 groove barrels and the original "S" ammo did not have a .323 dia bullet body [ just a small .323 band on a .321 body ] , so there was no "gradually" squeezing a .323 to .318 . The "S" ammo was designed that way to also work in the original .321 barrels as well as the newer .323+ barrels . The later .323 body 198 gr "Ss" ammo was not designed to work with the older G-88's .321 bores as they were out of German service by then . The Romanian 154 ammo has the same type .323 band profile [ but is longer as it has a mild steel core under the lead ] as the German "S" ammo but is loaded to lower pressure. So it is easier on the original German .321 bore barrels, and even easier on the .323+ groove barrels as the under sized bullet makes less pressure in the .323. The above rifle "should" have a .325 groove barrel [ most do BUT it could be as small as .323 ] that will even lower the pressure more. So there is no problem with the Rom ammo in a .3215 or greater groove bore. The only way to know what to use in YOUR rifle is to slug the bore and use the correct size bullet . The throat on the original barrels is long already to clear the long original .3188 dia roundnose bullet, it is 2 times longer than what is need to clear the short, pointed "S" bullet. There is no need to "squeeze" a .321 dia "S" bullet into a .3215 groove original bore. The Czech barrels are different , and can be as small as .306 land - .316 groove. They were not made to use any of the German ammo, the Czech G-88 ammo has a .316 dia bullet and is loaded to a much shorter lenght. Shooting them is a whole different story. mag
 

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Doc, great as usual!

May I ask a favor from you? The nature of the "S" conversions in Gew 88 and in Mannlicher M.95 is deeply misunderstood. Would you write a short, but comprehensive exposé on the subject and I will make it "sticky"? Please?
I could write you one that would match every rifle you would ever see. The main problem is that there was never a "S" conversion as such done on Gew-88 rifles, there was a 05 update that was a conversion. The "S" is NOT a bore size, it has to do with ammo. You are correct in that the Gew-88 "S" conversion is deeply misunderstood. mag
 

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Please, go ahead, mag! I would really appreciate a concise write-up on the modification ("05 update", "S-conversion", I can go on with the etymological juggling, but that's not the point. What do we call the Z-conversion, a "Z-update"?). It is fairly simple with Mannlicher M.95, but surprisingly controversial in case of Gew 88. Most importantly, bibliography, not just personal opinions, as quoting an authority on the subject will really nail the issue where it belongs.

Thanks in advance and let's not turn this into another ".308 vs. 7.62 NATO" fight, please.
 

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Since the questions always come when someone is trying to shoot their Gew-88, I would call it more mechanical than linguistic. If they are going to be shooting the rifle, they should know the safe way to do it. The .318 bore myth is the first problem and is compounded by the "S" means it is a .323 bore. Those can cause problems that are dangerous as saftey issues, or just spending alot of extra money to make incorrect, poorly performing ammo. The original German bores were not .318 groove, just the bullet was .3188. So when people are told to buy .318 bullets, they are wasting their money. The "S" stamp is not a bore size, it does not mean the throats were lenghtened. The original p-88 ammo needed atleast .666 clearance from the case neck to the land to clear, the later "S" ammo only needs .315 . The main body of the "S" bullet is .321, the original groove is .321, so they fit and do not need to squeeze anything. The OD of the case neck on original P-88 ammo is from .346 to .348 and on original "S" ammo it is from .348 to .350. Most military chambers are over sized, my G-88's chamber neck ID is an average .354, my Gew-98's are .360 . The "S" stamp means the original G-88's neck ID was checked and if it was by chance on the extra small side it was neck reamed to clear the .002 extra ammo neck dia. That is why most G-88s rifles still have the old P-88 sight on them, they were just cleared to fire "S" ammo if needed. There was another "S" stamp [ rare ] if the rifle was also sighted for the "S" ammo. The South American import G-88's still show the "S" stamp, but many have Czech barrels that are as small as .306- .316. People are still being told they can shoot .323 bullets in those. So that "S" means nothing now. The Czech barrels are the same size as German civilian barrels, too small for the .3188 dia military ammo. The German civilian ammo has a .316 dai bullet , as does the Czech military ammo. So a .318 bullet is not correct for most Czech barrels either. Since most "S" stamped rifles had nothing changed, it is not a "conversion" of anything. The '05 update was a conversion, as the magazine loading was changed to stripper clips. The notch was not cut for the "longer" "S" ammo as the "S" round is only 3.17 long compared to the P-88 round's 3.24. If you put a tape block across the notch and then Correctly load a clip full of "S" ammo you will see there is still .10 clearance between the tape and bullet. The distance from the rear of the guide and the top of the receiver if there was NO notch is 3.30, the "S" ammo in a stripper is only 3.20 long, there is extra room. The over hang of a partialy inserted stripper does not matter as the ammo will follow the clip back to the rear of the guide. If you load a stripper full of the older P-88 ammo you will see that the notch is a guide for the P-88 bullet tip, it fits perfectly and it is tapered to guide the round nose bullet. Plus the extra space of the notch is needed as the P-88 ammo in the clip is 3.38 long. The "Z" was not really a conversion, just the next bore size on new made rifles after 1896+. A change, but not a conversion. When older rifles were rebarreled after 1896 , they got the "now in use" barrel. It was not a conversion to those either as ONLY repaired rifles got them, if the old .321 barrel was still good it stayed. With ORIGINAL barrels the bores sizes where: 1889 to mid 1890- .314 - .3215 ,,, Mid 1890 to mid 1896 .311 - .3215 ,, Mid 1896 to end - .311 - .323+ . What I have said here matches everyone of the 100's of G-88's I have checked, I have never seen one that does not, so I am sure it will be true for a rifle someone else is trying to shoot. BUT THEY STILL NEED TO SLUG THEIR BORE to see what barrel they HAVE, and not go by what they have been told, there a a few shooting "websites" that are telling people .318 or "S" = .323 and to shoot that without checking. Everything I have said can be checked if you have a rifle, ammo, clips. mag
 

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Wow... well done, now as far as ammo is concerned: 8x 57 J = Original (for German barrels), 8x57 JS = not compatible. (newer, higher power at your own risk). Czech barrel = crapshoot, depending on bore dia.s

Where does the 8mm Mauser fall. is 8x57J the same as or comparable to 8mm Mauser?
I think this is about the only thing that hasnt been covered by this tread so far.

http://www.sportscomet.com/Hunting/184306.htm

I found this Link which details the differences between EU, and USA

Gotta Love it:
I = J, IS = JS

US Manufactures 8mm Mauser = 8x57 JS
and the 8mm Mauser J is the smaller sabot, however SAAMI limits the pressure for both loads to "safe" levels for the 88's

European Mfr 8mm Mauser = 8x57 J
8x57 JS = 8x57 JS If I read the article right.
Think about it, the 8mm Mauser round is older than the Gew 98's which are what introduced the round to the US, Thus, OUR 8mm Mauser is the opposite if the European 8mm Mauser.


Correct me if I am wrong.
Findings:
PPU 8mm Mauser is the smaller projectile, and lighter load, and 8x57 JS is larger projectile ( generally speaking One still must use caution when purchasing ammo)
http://www.prvipartizan.com/rifle.php Check that the Mauser energies are less than the JS energies.
In comparison, Remington Ballistics for the 8mm Mauser (limited by SAAMI)

http://www.remington.com/products/a...omparative_ballistics_results.aspx?data=R8MSR Remingtons ballistics for 8mm Mauser which is almost identical to Winchester.
http://www.winchester.com/products/...symbol=X8MM&cart=OG1tIE1hdXNlciAoOCB4IDU3KQ==


Note convert J (joules) to ft-lb 3000 J = 2216 ft-lb. and 2100 ft-lb = 2847 J

Rem-Chester 8mmMauser loads are almost identical to PPU 8mm Mauser loads (some PPU Mauser loads are hotter)

*sigh*
 

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..
Think about it, the 8mm Mauser round is older than the Gew 98's ...
Mauser has nothing to do with 7.9x57 I (or 7.9x57 J). The round was designed by Gewehr Prufungs Kommission for Gew 88, also designed by GPK.
 

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Nearly every single publication has perpetuated & republished incorrect information regarding bore sizes.

The correct specs & information is as follows.

1888- 1890 .3215" / .314 These are the original rifling specs that were discontinued because the bore wore out too quickly.


1890- xxx .3215" / .311 This is the "standard" Gew.88 rifling configuration. Probably 90% of Commission Rifles will fall in this category.


1896-xxx. 323+" / .311 These are the "Z" marked rifles.
These were the first german rifles to have these specifications.


189x-??? .318" / .311 A small minority of Gew 88 fall into this category.


1920- 30s . 318" / .308 The Czechs made replacement barrels for Gew 88s and are commonly found on 88s from South America. These can be identified by the presence of Czech proofs, and a Z in a circle under the shroud.
 

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Mauser has nothing to do with 7.9x57 I (or 7.9x57 J). The round was designed by Gewehr Prufungs Kommission for Gew 88, also designed by GPK.
OK.... the 7.92x57JS commonly referred to as 8mm Mauser..... unless you are in Europe than the 7.92 x 57 J is the "Mauser" to echo others... lets not split hairs. This is INFORMATIVE. I was simply offering observation as to a Possible evolution of Common names and distinctions between rounds... The empahsis is on Safety, and yes the 8mm Mauser round was conceived as the 7.92 x 57 by th "commission" for the Commission rifle, not a Mauser. **SIGH**
 

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Nearly every single publication has perpetuated & republished incorrect information regarding bore sizes.
Including yours, very notably so.

Please would people FINALLY desist using incorrect numbers and rounded-up and rounded-down approximations when treating a thoroughly METRIC cartridge, of which all specifications, sources, CIP norms etc. are and always have been metric? Such malpractice is only distorting and falsifying where precision counts.

Carcano
 

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Including yours, very notably so.

Please would people FINALLY desist using incorrect numbers and rounded-up and rounded-down approximations when treating a thoroughly METRIC cartridge, of which all specifications, sources, CIP norms etc. are and always have been metric? Such malpractice is only distorting and falsifying where precision counts.

Carcano
Gotz, Walter & several others are wrong.

The specs I posted are correct within .0005
 
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