I need reloading data for Jap 7.7

Oakie

Only for a 180 sp bullet. I have alot of manuals but they only have it for 150 and 174 grain bullets which I have. I have alot of 180 grain bullets but no data for them. Thanks Oak

gesshots

Cartridges of the World lists one load for a 180gr. bullet:

45grs. IMR-4064 ...... 2490fps. ......Duplicates factory ball ammo

navc130

Looks like you can use any load for the 30-40 Krag, .303 British or 7.65 mm Argentine. Their loads are one to two grains less than the loads for the 7.7 mm Jap: same bullet weight.

jonk

174 is close enough and the Jap action strong enough that you can use that data; just start at the start loads and work up as normal, just leave about 1/2 to 1 grain off listed max.

Mk 19

I just loaded up a bunch of 7.7X58's with non-lead ammo for deer hunting in CA, the load was Norma Brass, CCI 200 primers, Barnes 180gr TSX over 46.5gr of IMR 4350, it was a nice accurate load and took down a 175lb mulley with a 150 yard shot.

Lyman's 46th Edition of 1982 shows these loads for a 180gr jacked SP
IMR 3031, 39.0gr @ 2202 to 43.0gr @ 2444
IMR 4895, 42.0gr @ 2304 to 46.0gr @ 2564
IMR 4064, 42.0gr @ 2227 to 46.0gr @ 2512
IMR 4320, 43.0gr @ 2309 to 47.0gr @ 2590
IMR 4350, 47.0gr @ 2207 to 51.0gr @ 2538 (Compressed Load)
H-380, 45.0gr @ 2237 to 50.0 @ 2525

I always keep my old manuals laying around as they have info that has been dropped from the new editions. Word of warning, some of these old manuals have up to 10% higher powder charges than what is recommended today, work up your loads slowly and watch for pressure signs carefully.

shastaboat

Ok, some years ago my father (now deceased) gave me his 7.7 Jap he picked up on Saipan. He was a Lieutenant in the 4th Marine Division. As a kid I remember the rifle up in our garage rafters collecting dust and a light coat of rust. Anyway my dad said I was the only gun nut in the family and said, "Now don't go shoot it!" Well I never did listen very well and started to clean the rifle up. It had numerous bit's of shrapnel in the stock and I suppose that is why the original owner didn't have it any more. To my surprise the bore was pristine, being chrome-lined. I read up on the actions from P.O. Ackley and decided to give it a go. Not having any 7.7 brass I made some up from 30-06 brass with the aid of a set of Lee dies and case trimming. The brass did expand at the web as I anticipated but still maintained tight primer pockets. Commercial brass is now available. OK, here is my final load. I used a 174 gr. Hornady round nose bullet .312 with 50 grains of H380 and chronographed that load at 2750 fps. I was able to shoot a 2.75" 100 yard group but had to drift the front sight about 3/32 to the right to get it to print on the target. That may explain why the original owner no longer owned the rifle. I stopped load development at that point but had shot some Sierra 180 gr. SP .311 over 45 gr of IMR 4320 at 2383 fps. I think that if you started with 47 gr of H380 and work up with the Sierra 180 gr. bullet you might be able to get 2700 fps safely. Anyway, I took the above target and showed my dad and he just shook his head....

Oakie

thank you everyone.