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View Full Version : GEW88, 8mm w/.318 bore-324 cast?



straightshooter1
05-03-2006, 11:35 AM
I have recently acquired a GEW88 8mm rifle with a very nice bore made in 1890. It has the "S" on the receiver, but, much to my surprise and despite what I would have expected with the "S" marking, it has the old .318 bore.

I have been told that I could shoot .323 condoms with reduced loads safely in this old blackpowder rifle. I would load them at something like 21 grains of 4198, 16 grains of 2400 or 21 grains of Reloader 7.

I thought, with the same loads, I could shoot .324 190 or 210 lead round nose gas checked cast through it as well. I have not tried any and, for the purposes of my questions, am assuming I can chamber a round that large in the gun.

Has anyone had any experience with shooting boolits as much as .06 larger that the rifle is made for? Especially in an oldie like this?

I have routinely gone .02 over with no problem (.310 in a 308/30'06 or .266 in a 6.5) but .06 more seems a lot.

Thanks in advance for your thoughts.

Bob

Bob S
05-03-2006, 12:05 PM
I have recently acquired a GEW88 8mm rifle with a very nice bore made in 1890. It has the "S" on the receiver, but, much to my surprise and despite what I would have expected with the "S" marking, it has the old .318 bore ....

Bob

Bob:

How did you determine that your rifle has a .318 groove diameter? (I assume you meant groove diameter, not bore diameter) If you actually slugged your barrel and got .3180, I'd be really surprised, as I've never seen one with a .318 groove diameter. Nothing at all was done to the bore on "S" marked rifles: only the neck and throat were reamed slightly larger for the S-Patrone ammuntion. The bore and groove diameter remained the same. I have a half dozen of these with excellent bores, and they all mike out between .3205 and .3210" in the grooves. All of mine will easily chamber cartridges with 323471, cast of wheel weights and sized to .324, without resistence, and will shoot excellent groups with no problems. For jacketed bullets, I use the Speer .321 "flat point" that is made for the 32 Win Special. I use that one because it is really a "semi-pointed" design, the meplate being just barely enough to cover a large rifle primer.

If you have a Turk M88/35, which is the one with the semi "pistol grip" stock, no barrel shroud, and a Mauser tangent sight, you will probably find that the groove diameter will be the usual .3235 to .3245.

Regardless, a chamber cast and careful bore slugging will show what your particular rifle will handle. Even if you have the latter-day Turk, the Commision action is a *very* "small ring" action, and is not capable of handling a steady diet of S-Patrone or equivalent. One of my rifles is a Turk-marked 88/05 (staight grip, barrel shroud, but modified for the Mauser stripper clips instead of the Mannlicher-style charger). Upon disassembly after purchase, I found the recoil lug cracked almost clear through. I'm willing to bet the cause was firing a lot of that Turk 7.92 mm x 57 ammo that has hit our surpluss market in the past few years ... it seems awfully "hot".

Resp'y,
Bob S.

straightshooter1
05-03-2006, 12:33 PM
Yes, groove diameter is correct. I slugged the bore, couldn't believe it myself, took it to my buddy who has a commercial reloading business & he "confirmed" by measuring the barrel just inside the crown with a caliper. Right at .318, he said.

I had used a .324 bullet w/o gas check, drove it through the bore, used my micrometer to measure. Was going to do it again with a soft lead sinker.

My rifle is still in the original configuration, barrel jacket, etc. It has been "turked" in that the rear sight is Turkish marked, the bolt is Czech, all else is German.

I have another, an 88/35 and it is one of the most accurate rifles I have ever owned at 100 yards. Amazing with cast or condoms. I never slugged the bore as I believed that it was a "standard" one as you describe. But, I think I will do so when I get the chance.

Bob

Bob S
05-03-2006, 12:52 PM
Bob:

You may have a Czech barrel, too. Some of the ex-German, ex-Turk 88's were refurbished in Czechoslovakia and sent to Equador (? ... or another South American country) The bolts had to be replaced because the Brits (after capturing a large number of the rifles during WW I) removed the bolts and tossed them in a pit someplace so the rifles could not recovered and turned against them again. A considerable number of these found their way to South America "between the wars". According to Doc AV, the Czech replacement barrels were "tighter" than the original German ones, and had the original skinny exterior profile of the pre-1890 Greman barrels. I have never seen one of these. It may be what you have. If the bore is in excellent condition, that would be unusual: the South American rifles were usually "rode hard and put away wet".

At any rate, once you find a bullet that fits, I trust you will find it shoots fine and will be a lot of fun.

Does yours have the "stripper clip" mod, or does it still use the Mannlicher clip?

Resp'y,
Bob S.

straightshooter1
05-03-2006, 01:01 PM
This one is modified for the stripper clips.

I just got this from "Marcus" who posts on another forum. He is pretty well-known on that board for his collection of nice, older rifles. This one, he said, was one brought in back in the 50s by, I think, Interarms. Most finish gone, jacket not dented like so many, but obviously carried.

I wouldn't know how to id one of the "skinny" barrels either. I intend to re-slug the bore with a soft lead sinker, maybe tonight, and double-check myself.

Still hoping, if it is a .318, some experienced cast shooter will say whether .06 over is too much (again assuming I can close the bolt).

Bob

Dale53
05-03-2006, 04:45 PM
straightshooter1;
Your bore is not .06" under size - it is .006" undersize. Not being a "sharpshooter" but just trying to be helpful.

Dale53

straightshooter1
05-03-2006, 10:31 PM
Waaaay back in the early 50s, addition, subtraction, multiplication, even division was not too hard. Then, about fourth grade, came fractions, then decimals. I was lost.

So, many, many years later, after I'd gotten a Masters in Urban Police Administration (no math), I had to make a choice. Law School or the Phd program.
The Phd program had math (statistics)-Law School didn't.

Hence my inability to remember or distinguish between hundredths and thousandths as I chose the path of least resistance.

You are right. .006 oversize. Still, is that too much?

Bob

Buckshot
05-04-2006, 01:04 AM
"................I have been told that I could shoot .323 condoms with reduced loads safely in this old blackpowder rifle."

These aren't blackpowder rifles. Or let's just say they were Germany's first smokless powder rifle. Metalurgy differences between the M1884's and the M1888 Commision rifles aside.

These are the reason American manufacturers load current 8x57 ammo to about 36-38K pressures.

.............Buckshot

Char-Gar
05-04-2006, 01:04 PM
Straightshooter... It is a true joy to meet another Math Retard!!! I did OK through decimals and fractions, but when algebra and geometry came along , everything went south. I had to take High School geometry twice and algebra three time before I could squeak out a C from either.

When I went to College I chose a major (B.A. in Fine Arts) that did not require Math. After undergraduate shool I went to law school and picked up the J.D. again with no mater. A few laters I went back to school for three more years and picked up the Masters of Divinity, again with no math.

Through all of this I managed to stack up 148 undergraduate and 186 graduate hours without a single one in math. Some folks tall me this can't be done. Well I did it and have the transcripts to prove it.

I am not 64 years old and can't do more than basic math and truly don't give a ****! Folks that say you can't survive in life without advanced Math have never meet me.

My daughter is almost as bad as I am, but managed to get through Statistics to pick up a P.hd in Industial Psychology. The son eats number for breakfast and picked up a Master in Geology (Texas A & M) and knows some kinds of advance math that I can't even pronounce. If he didn't look so much like me, I might be concerned about his true parentage.

Math retards of the world unite!!!

straightshooter1
05-04-2006, 02:20 PM
They did actually make me take one math course-statistics. That was when battery powered calculators had just begun appearing and I purchased one for $35 from Radio Shack that was about the size of an early cell phone. Weighed a couple of pounds IIRC and using it was the only way I made it through. I wrote a thesis on the Use or Non-use of the Police Shotgun by Patrol Officers (I think that was the title) since I was a Police Sergeant at the time, paid some small user fee to the University to run the stats on something that resembled a UNIVAC and never looked upon math in any form again.

.006 not .06(pesky decimals)!

Urny
05-04-2006, 04:29 PM
I have a custom full stock Mauser with an original I bore. It's four groove, with one set measuring about .318" and the other set .319". The barrel is round to octagon to round again with integral rib and front sight base. Ike Ellis, who built it, called the action a 1904 commercial. No military markings of any kind anywhere, but it does have the stripper guide and thumb cut for stripper loading. To the point, the rifle was rechambered from 8x57I to 8mm-06 Ackley by a big name smith back east, and he provided fire forming loads with Sierra 175 grain
.323" bullets. The second shot bulged the chamber, and though Ike offered to make the damage right, it has been kept as a reminder to be careful about others handloads. Lee Shaver is willing to sleeve the chamber, and I think that is the way for me to go, now that fifteen years have passed and the pain is receeding.
Maybe it would pay to think a long time about those oversize jacketed projectiles.

straightshooter1
05-04-2006, 04:44 PM
Urny-appreciate the info. Am giving it lots of consideration. Looking for the input of the shooters on this site to help.

Kind of think I am still in denial about the size. Have visitation for my Church tonight, but if I get home before too late, will slug bore again. Just can't believe the .318.

If no time tonight, will do it tomorrow.


Bob

straightshooter1
05-05-2006, 09:57 PM
Had a chance to use the soft lead sinker and, sure enough, you guys were right. It is not .318, but right at .319. Gonna try one of the .321s made for the 32 Spec in one of my resized brass on Monday. Want to see if there is any friction when I put it in the casing of if my expander expands too much.

Still want to try the .324 leads as slow speeds-but still not sure.

Bob