7.7 Jap from 30/06 cases

[sigman2]

Hi folks,

I have a Type 99 that I want to reload for. Is it ok to form 7.7 from 30/06 cases? I made up 20 test loads and fired them yesterday. Accuracy was good. I did notice a little case expansion just above the case head due to the slightly larger chamber dimensions. Same as when I used to form 6.5x55 Swede from 06

The load was:
150 gr. .311" Prvi SPBT
40.5 grs. IMR 4064
WLR Primer
Cases from commercial 30/06
COAL 3.00"

Any comments or suggestions?
Any favorite loads?

Thanks

Information

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[cary m2a]

If they work, just neck size them and keep an eye open for case head separation.

Cary

[dabsond]

This article from another board sums up using 30-06 and 8mm mauser brass in the 7.7 jap.http://www.surplusrifle.com/shooting...pe99/index.asp

[TerryS]

The article says he slugged his bore and there was not much rifling left. He may not have known it was Metford rifling. My 99 is all numbered correctly, including the dust cover, and has never been disassembled (and paid for that). Have some converted o6/7.7 for it but have never fired it, yet.

[Jim K]

I once knew a fellow who built a nice collection of Japanese rifles quite cheaply. He would pull the bolt and show the owner that the rifling was "all worn out", making the gun about worthless.

Jim

[cary m2a]

Thats a good idea.

Cary

[musketjon]

I've had good luck making 7.7 out of ' 06 brass and have never had a problem shooting it and '06 brass is a lot cheaper than Norma. Go for it and have fun.
Jon

[dlampman]

I was out shooting my 7.7 Jap and my 8mm Mauser yesterday. Fired about 60 rounds from each gun. All the cases I used in both guns were made from 30-06 cases. No problems. I like to use military brass when I form anything out of '06 cases. I have found, over the years I've been doing it, that the thicker mil cases tend to split less often around the neck and shoulder.
HTH
Dave

[Jim K]

First, I did this under controlled conditions. I DO NOT recommend or suggest it, and hereby specifically warn against it. (OK, does that satisfy the "shoot only cartridges made for the gun" folks?)

For years, I have read about the "danger" of forming 7.7 brass from .30-'06, yet I knew it was done and have seen many such cases that showed no signs of expansion beyond what might be expected in any chamber that was at the "far side" of the tolerance.

Then I heard "war stories" that not only could 7.7 Japanese be fired in a .30-06 chamber, but that the Japanese clips worked in the M1903. So I got some 7.7 Japanese ammo (Norma, the original stuff is nearly impossible to get). Anticipating high pressure, I first fired a couple of rounds in a .30-'06 Remington 700, hooking the rims under the extractor. The results were normal; no case expansion, no signs of excess pressure. So I loaded up a Japanese clip and stripped 5 rounds into an M1903A3. All fed and fired normally, again with no signs of excess pressure. The case shoulders moved forward, leaving a short neck, exactly like the intermediate case shown in those pictures.

I did not test for accuracy, but I would have no hesitation about firing 7.7 ammo in a .30-'06 in an emergency.

AGAIN, I don't recommend or suggest this; a rifle should always be fired only with the correct ammunition.

Jim

[218bee]

Sigman2;

How did you prep the 06' cases?...I am looking to convert maybe 100 or so 06 cases into 7.7 Jap, but am having a hard time finding a forming/trim die...If you have one, could I rent it from you for a day or so, till I refoem the cases..

I would pay you for this rental, of course..

regards

218bee