Question about 7.7x58mm round

[Spaz86]

I looking into reloading(I am new to reloading) for my arisaka type 99 due to hard to find ammo does anyone know what the closest powder would be to the original WWII load. Cause i am thinking of using imr 3031 with hornady 150gr sst .312 bullets with ppu 7.7x58 cases.

[Dufus]

I would be more inclined to use H 4895. It is a little slower than IMR 3031.

[Jim Watson]

Ken Waters used H4895 of common US powders for 150 gr.

[Spaz86]

Ok i have been trying to work up a good spec as close to WW2 rounds as possible just to get a nice feel for the rifle for what it was but with modern day loads for safety reasons. I never really expected to own this rifle so now trying to keep it firing since i fired it a few times and it was just a blast to shoot.

[eastbank]

you can even use 8x57 mauser cases,if you can,t find standard 7.7 japanese. just full lenth size in the 7.7 die and your ready to go, i picked up several hundred 8x57 cases years ago and that,s mostly all i have used, untill privi started making 7.7 japanese. eastbank.

[T. O'Heir]

The 7.7 x 58 was loaded with a 181 grain bullet giving around 2400 fps from the Type 99’s 25.75” barrel.
Hodgdon's site has 180 grain data, but it's slightly slower than that out of a 26" barrel. Lots of 7.7 Jap data on Reloader's Nest.
Hornady makes a .310.5" 174 grain FMJ that would do nicely. Any bullet made for the .303 Brit will work though.

[Reloadron]

Cartridges of the World 13th Edition Page 386:
130 grain SP IMR 3031 46 grains 2950 FPS Duplicates Factory Loading
180 grain SP IMR 4064 45 grains 2490 FPS Duplicates Factory Loading

The only reference to "Ball" is the 175 grain bullet and the ML (Military Load) delivered a muzzle velocity around 2400 FPS.

Ron

[Unclenick]

CAUTION: The following post includes loading data beyond or not covered by currently published maximums for this cartridge. USE AT YOUR OWN RISK. Neither the writer, The Firing Line, nor the staff of TFL assume any liability for any damage or injury resulting from use of this information.

With the 150 grain bullet being just shy of the middle of that weight range, it validates H4895 as a good candidate. A powder that works well at reduced load levels is desirable here, and H4895 fills that bill, too. However, case fill for H4895 at the Hodgdon maximum (44 grains) is only 82%, so a magnum primer may give better velocity consistency with it. Both 4064 (45 grains) and Varget (46 grains) give about the same pressure and velocity in QuickLOAD, but fill the case closer to 88% and will therefore be less likely to be improved by a magnum primer. All worth trying to see which one shoots best for you and fouls least.

[44 AMP]

CAUTION: The following post includes loading data beyond or not covered by currently published maximums for this cartridge. USE AT YOUR OWN RISK. Neither the writer, The Firing Line, nor the staff of TFL assume any liability for any damage or injury resulting from use of this information.

This data for information ONLY!!

1970 Lyman manual
"factory duplication load"
180gr bullet
IMR 4895
44.8gr
2500fps

Test gun listed as "Japanese service rifle, 25" barrel"

Norma cases
Rem 9 1/2 primer
Remington 180gr S.P.C.L. No. B22812 bullet

The max load listed for IMR 4895 and this bullet is 46.0gr vel 2564fps.

Hope this helps.

[Spaz86]

44amp that does help out alot i do thank everyone for helping me out. With being new to reloading cause i am tired of seeing my old rifle as a wall hanger almost since i got it only have taking it out a couple of time's. That old girl was sitting for 60+ years before i got it and it deserves better then just to sit around.

[44 AMP]

YW Spaz86.

Commercial cases are available, though the supply is spotty, and never at bargain prices. Usable cases can be formed from .30-06,(some trimming required) and even 8mm Mauser (less trimming needed, if any), but not many of us have excess reloadable 8mm brass running about, like we do with 06.

Loads should be CAREFULLY worked up, in small steps from a 10 or 15% reduction from published data. One NEVER knows just which gremlins have taken up residence in these old guns over the years, and the components we use are never the same as the ones used in testing to create the published data. (especially if using cases formed from something else)

One thing to keep an eye on, is the stock. Arisaka stocks are typically multi piece and the glue used might have deteriorated over the decades. One of mine had the forend separate from recoil firing standard level loads. (there was no damage, just the pieces came "unglued". A simple repair, just something to keep an eye out for....

[Spaz86]

I have fired 60rds of graf&sons sp ammo though my t99 but its only for sale once a year for the hunting season. Grafs ammo is nice stuff its quoted at "2650" fps at the muzzle. I have had great luck with the ammo my rifle loves it but with how hard it is to get i figured it best to move to a reloading setup.

[F. Guffey]

Commercial cases are available, though the supply is spotty, and never at bargain prices. Usable cases can be formed from .30-06,(some trimming required) and even 8mm Mauser (less trimming needed, if any), but not many of us have excess reloadable 8mm brass running about, like we do with 06.

I use forming dies, my favorite forming die is the 308 W forming die, if I had one forming die I would have one 308 W forming die, if I had two forming dies the second die would be the 243 W forming die. Commercial cases, I like commercial cases for using as comparators. And then there is the length of the chamber from the shoulder to the bolt face; when I form 7.7 Japanese case from 30/06 cases there is no way I can mill the fit between the chamber and formed cases. After I reach for the forming die I reach for the man tool; that would be the hack say and for finesse I use the file.

F. Guffey

[F. Guffey]

If you choose to use 30/06 cases and if you form 100 cases it will be necessary to trim 21" of brass, if you choose to use 8mm57 cases it will require 4.4 " of trimming.

F. Guffey

[44 AMP]

If you use a powered trimmer, its the same amount of work, but if you don't (like me) you can use a tubing cutter to save a LOT of cranking cutting 06 down to 7.7Jap. Still need to do some trimming though.

I used the 7,7 sizer die (decapping stem removed) to form the 06 cases. Size 'em, then cut off the excess. trim, chamfer, size them again with the expander ball in place, check chamber fit, and load.

I won't say its the best method but it did work for me.

[F. Guffey]

If you use a powered trimmer, its the same amount of work, but if you don't (like me) you can use a tubing cutter to save a LOT of cranking cutting 06 down to 7.7Jap.

I raise the ram, I then hit the protruding neck with the hack saw and that is it.

I have 100s of air craft countersinks, they also work, the nice thing about using the air craft countersink happens when the ram is lowered; the neck being trimmed simply separates. I know, everyone is confused but without a countersink the better tool is the hack saw.

F. Guffey