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-   -   7.7 Jap and .303 British (http://forums.thecmp.org/showthread.php?t=248393)

Jtbaker1989 07-03-2019 07:42 PM

7.7 Jap and .303 British
 
I recently picked up a nice type 99 Arisaka rifle in 7.7 Jap. Still has the crest on it. Awhile back I got some reloading dies made by Pacific for .303 British. On the package the dies were in it said “.303 British/7.7 Jap”. I plan on making the 7.7 Jap brass out of 30-06 brass but wasn’t sure if these Pacific dies can actually size for the 7.7 Jap. I use them often for the .303 but don’t trust whoever wrote on the package. Thanks for your help.

Chuck G 07-03-2019 07:46 PM

bullets are the same for both calipers but brass NO.

Jtbaker1989 07-03-2019 08:05 PM

Thanks Chuck. I will be ordering some 7.7 dies

7,62x51mm 07-03-2019 08:05 PM

two early 303 Brit and a 7,7 jap for Lewis m/g
 
http://oi65.tinypic.com/2zzu629.jpg

7,62x51mm 07-03-2019 08:08 PM

headstamps 7,7 Jap is their 303 loading for Lewis m/g
 
http://oi63.tinypic.com/2vcjd4j.jpg

Jtbaker1989 07-03-2019 09:14 PM

They almost look identical

bigwagon 07-04-2019 06:09 AM

The rimmed version of the 7.7 Jap was only used in machine guns, not the Type 99 infantry rifles. Not sure if you can use the same dies for both.

BRMPCF50 07-04-2019 09:53 AM

The 7.7x56R is the same as the .303 Brit. Used in aircraft machine guns and Japanese Lewis guns.

Japanese rifles used a 7.7x58 rimless round.

https://en.m.wikipedia.org/wiki/.303_British (scroll down for info on the Japanese version)

jeremy69 07-05-2019 03:40 PM

I just bought the dies and brass from Grafs when I got a 7.7, was not worth the risk to mix the formed 30-06 back in with my real 30-06. I think it was $50-60 for 100.

navyrifleman 07-06-2019 06:54 AM

The bullets for the .303 British, the 7.7mm Jap, and the Russian "7.62mm" are generally the same.

I cast a 160 grain lead bullet in a Lee mold which was designed for the AK-47's 7.62x39. It comes out of the mold as .312, but can be resized down very easily. This bullet can be used in all of the above as cast. I have found this bullet, sized to .309 to be very accurate in my 30-06 as well.

The 7.7 Arisakas vary a bit in bore size. Consider slugging the bore and checking the exact size with your micrometer, then size your cast bullets accordingly.

You are doing the right thing by getting a set of dies made specifically for the 7.7 Jap. You CAN resize 30-06 brass in a 7.7 Jap die but you will have to trim the neck down afterwards to proper length. I always take a red permanent marker to the bottom of all my resized brass so that I don't accidently mix them in with similarly marked 30-06 brass.

Carefully inspect all your shells after firing. I have a couple of Arisakas which have a tendency to bulge the cases, which leads to a short life for the brass.

The Arisaka is one of the strongest bolt actions, but headspacing and varying chamber tolerances can be a problem.

You may have to refer to some older reloading manuals for load data.

Best of luck with your new rifle.


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