7.7 Jap reloading data.

Johnharley

Does anyone have any load data on the 7.7 Jap cal? I have been looking for a few months for bullets. I finaly came across some Sierra 125g spitzers. I can find reload data for the 150 and 174gr but no info for the 125. If anyone has a load they would share or a resource they could refer me to I would really appreciate it.

Dundee Tom

I have a Type 99 and have learned that it is basically the same round as the .303 British Enfield, but rimless. That being the case, it seems you could use the British .303 loading data. Here's a link to one such sight:
http://www.303british.com/id9.html
Remember the Arisaka rifle is known for the strength of its action, which surpasses the British Enfield, Mauser and U.S. Springfield 1903.

44shotdoctor

All I could find was a load in a 130gr sp load. It calls for 47.0 of 3031 powder. 3018fps.
This load came for a NRA publication of Handloading published 1981.
You are basically asking for something that isn't around and in the weight you are asking for.
Hope this helps.

Rocky Raab

Both versions of the "7.7 Jap" have about 63 grains of water capacity, as do the 303 Brit and the 7.62x54R Russian round. All are also about the same as to maximum pressures allowed. That being the case (pun intended), load data is largely interchangeable among them all - at less than absolute maximums, of course.

Hope that helps.

jonk

I certainly don't advocate this BUT...

the Japanese Arisaka is documented to be the strongest military action ever made. I doubt you could stuff enough powder of any rifle type into that case to hurt it with that light bullet.

In general data for a HEAVIER bullet is safe to use with a LIGHTER one. So feel free to use the 150 grain loads. Given the 125 grain bullet I'd feel safe in jumping to the middle range of start-max loads AS a start and be willing to work up from there.

The fact is you probably aren't going to find a published load for this weight bullet in this cartridge so you'll have to expermient within the realm of safe practice as well as possible.

Johnharley

Thanks for the info Guys. I emailed Sierra and the best they could offer was some 1972 data from a magazine. I was looking for something a little more current. I will lok at some more of the 303 data. Any more opinions from Arisaka type 99 owners would be great.