xausa
.400 member
Reged: 07/03/07
Posts: 2037
Loc: Tennessee, USA
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I have a nice Husqvarna commercial (.30-'06 length) M98 in 8X57IS which I would like to have rechambered to 8X64S. The drawings I have of the two cartridges from an authoritative German source (DEVA) shows that the neck diameter of the 8X57IS is slightly larger that that of the 8X64S, so there is some question in my mind as to whether the 8X64S reamer will clean the old chamber up.
Since the distance from the base to the neck of the 8X64S is 55.51mm and the 8X57 case is (naturally) 57mm long, at most only 1.49mm (.0586")of the neck would be oversized, and then only by .12mm (.0047"), the difference between 8.96mm and 9.08mm. (.3527" and .3574")
Since the 8X60S has a 8.99mm neck, and it was specifically designed to convert 8X57IS rifles from the forbidden military caliber to a larger legal cartridge, it does not seem that this alteration would be a problem.
Has anyone had any experience with this conversion?
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tinker
.416 member
Reged: 12/03/05
Posts: 4835
Loc: Nevada
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the neck for a 318 gun will be smaller in diameter than the neck for a 323 gun
8x64 is a 323 round
is your barrel a 323 barrel?
--tinker
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xausa
.400 member
Reged: 07/03/07
Posts: 2037
Loc: Tennessee, USA
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Yep, it's a 8X57IS (.323" bore). I doubt that Husqvarna ever made a .318" barrel. The 8X57I has a neck diameter of 8.99mm (.3539"). I have verified that my Husky has a 9.09mm (.3578")neck. No problem in that regard.
The same problem crops up with trying to rechamber a 7X57 to 7X64, but the difference in neck sizes is greater: 8.23mm (.3240")vs. 7.95 (.3129").
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tinker
.416 member
Reged: 12/03/05
Posts: 4835
Loc: Nevada
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It's time for a chamber cast.
Find out exactly what is going on in your chambers before you fret over drawings.
What's real in your gun is more important than what appears on a spec sheet.
--tinker
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shinz
.300 member
Reged: 11/05/08
Posts: 135
Loc: New Zealand
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Quote:
It's time for a chamber cast.
Find out exactly what is going on in your chambers before you fret over drawings.
What's real in your gun is more important than what appears on a spec sheet.
--tinker
What he said.  Even if you had to get the neck of the 8x64 opened up to the slightly larger diameter with a neck reamer after the rechambering, I can't see .005" being of any significance. But do get a chamber cast done, & find out exactly what you're dealing with rather than maybes.
Steve
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Nakihunter
.375 member
Reged: 13/10/07
Posts: 588
Loc: New Zealand
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Reading Ken Waters' Pet Loads on the 7X64 will tell you the result of rechambering a rifle with different neck diameters. His rifle ended up with fired cases having a step in the neck from the old 7X57 neck being larger than the 7X64 one. The simple solution is to set the barrel back a couple of turns to get rid of the old neck with the new case body / shoulder.
--------------------
Always shoot through the target & not just at it.
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xausa
.400 member
Reged: 07/03/07
Posts: 2037
Loc: Tennessee, USA
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Problem solved: I called up Hugh Henriksen, who has made a number of reamers for me in the past. I was reluctant to ask Hugh, because he is generally covered up with orders, but as it turned out, he had a roughed out 8X64S reamer in stock, and because it had not been finish ground, he will be able to grind the neck to the same dimensions as that of the 8X57IS (9.08mm/.357"), AND he will be able to get it to me in a couple of weeks!
Incidentally, I can recommend Hugh unreservedly. His work is right up there with that of the late, great "Red" Elliot.
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farshot
.300 member
Reged: 25/01/06
Posts: 106
Loc: Alberta Canada
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Maybe a little off topic, but have any of you fellows found a good load for the 8x64S? I have a very good condition BRNO ZG-47 in same, and I am trying to use 200 gr Nosler Accubonds and Vitivouri (sp) 150 and 160 powders. With the V-150 at 54 gr I am getting about 2560 ft/s but with very hard bolt lift.
With 58 gr V-160, I am about 2400 ft/s with no stickiness but lousy velocities - I may as well use my 8x57... I would hope that I can get to above 2600 ft/s with 200 gr bullets in an 8x64 - maybe I am wrong.
I am about to try RL-15, but thought I would ask here as someone may have gone down this road.
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xausa
.400 member
Reged: 07/03/07
Posts: 2037
Loc: Tennessee, USA
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My loading manual published by DEVA, the German institute for research on hunting rifles and ammunition, lists a tested load for the 200 grain Nosler, using Brenneke cases, of 58 grains of Vihtavouri 550 for a velocity of 832 mps (2730 fps.) They describe the pressure as maximum (4050 bar).
They also list a maximum pressure load for the same bullet using 64 grains of Hodgdon H4350 at 825 mps (2706 fps). I think I would work up to those loads cautiously, especially if you are using cases formed from .30-'06 or .270, since the case capacity may vary.
The same manual suggested a load of 60.3 grains of IMR 3031 behind a 232 grain Norma Vulkan bullet in my 9.3X62. Since this would have been a heavily compressed load, I backed off to 54 grains and still got very flat primers, using cases formed from Federal .30-'06 brass. I have not checked the velocity. The recoil in my little 1952 Mannlicher-Schoenauer carbine is significant, however.
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farshot
.300 member
Reged: 25/01/06
Posts: 106
Loc: Alberta Canada
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Thanks xausa -- those are the velocities I would expect, but I also wonder if I will be able to get to them. I use HH 8x64 brass from Europe (not cheap - but original) and the rifle is good and strong so i will see what I can do if I can find some Vit 550. The H4350 would make sense as well.
As an aside - I just missed buying a MS carbine in 9.3 x 62 and I wondered how that round would push you around in that rifle. I use that caliber in my Sig 970 and BRNO ZG47 and they can be stiff, but a wonderful round.
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Yochanan
.375 member
Reged: 26/01/03
Posts: 912
Loc: Volksdiktatur Schweden
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xausa,
Set back the current barrel a few threads and clean out the old chamber completely. I have had two ZG-47 in 8X64S, dies etc. is already difficult to obtain.
Using 8X57IS dimensions for 8X64S Brenneke will give you a wildcat, harder to find dies etc.
Cheer
Johan
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© "I have never been able to appreciate 'shock' as applied to killing big game. It seems to me that you cannot kill an elephant weighing six tons by ´shock´unless you advocate the use of a field gun." - W.D.M. Bell: Wanderings of an Elephant Hunter.
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xausa
.400 member
Reged: 07/03/07
Posts: 2037
Loc: Tennessee, USA
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Johan,
--- When you have no basis for an argument, abuse the plaintiff. ---
Or as we say, "When the facts are against you, argue the law; when the law is against you, argue the facts; when both the law and the facts are against you, just argue!"
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farshot
.300 member
Reged: 25/01/06
Posts: 106
Loc: Alberta Canada
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Johan and Xausa
Or as we say, "When the facts are against you, argue the law; when the law is against you, argue the facts; when both the law and the facts are against you, blame the client".
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