7.7 Jap data

[pe4king]

Hi all, after acquiring a type 99 rifle I am struggling to find any load data using Vihtavuori powder namely N140 or 135 with a 180gr bullet, there is quite a bit of available data using American powders which I have none to hand.
Has anybody already done this exercise and could help ?.

[WelshShooter]

I recall seeing some load data for this calibre in the Ramshot sad data recently. I just checked this quickly and there is data using Accurate 2700 and Accurate 4350. These are for 150gr and 180gr bullets.

Seeing as Lovex powders are identical to Accurate powders, it might be worth checking a local RFD/gunshop for the correct Lovex powder?

[pe4king]

Thanks for the info, however I would really like to stick with The Vihtavuori or even Reloader Swiss powdersif at all possible.

[kennyc]

try contacting the reload swiss customer service team they are known to be pretty good about sending data out, also the interweb would seem to suggest .303 data is comparable (although lower performance in this application, however as always you need to do your research and ideally get confirmation from a manufacturer and then work up a load )

[dromia]

My accuracy load with 174 gn bullet used to be 39 gns N140.

Around 2,200 fps as I recall, I am currently away so cannot give exact details, it wasn't a maximum load but getting there.

Start load at 37 gns should be fine with 40 being a conservative maximum, just work up carefully.

[pe4king]

Thanks Adam, it ties in very well with a discussion I had earlier with SimG

[ukrifleman]

You can pretty much use .303 load data for the 7.7x58 jap cartridge, as both use the same FMJ bullet weight and diameter.

The Type 99 Arisaka in good order, is a much stronger action than a Lee Enfield and has a larger case capacity than a .303, so you have some wriggle room for load development.

I would recommend that you contact the powder manufacturers of your choice for specific load data.

I have done this in the past with both Ramshot and Reload Swiss and have received excellent information that was not available in their respective published powder load guides.

ukrifleman.

[pe4king]

Thanks for the advice chaps.

[lasbrisas]

I use 44.2gr of N140 with a 174gr Prvi .303 bullet in my Type 99, I also have a type 38. I use N140 in most of my Milsurp rifles with good results, 11 different calibres all together.

[pe4king]

Thanks for the input guys, I tried 39gr of N140 it was a very mild load with the case, only just obturating enough to seal the chamber, some soot was visible on some cases, the primers were not flattened and barely expanded into the pocket, but was a good starting point, I will work up from there, prior to asking questions I was thinking around 43 grains, so will start cautiously working up some loads.