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Discussion Starter · #1 ·
I'm starting to reload for my old Arisaka.

I'd like to 150 grain hot-cor through paper at a moderate ~2350 fps velocity (this gives it a similar point of impact to a full power 180 grain round). I have BL-C(2) and H380. I first planned to use H380, but may switch that up.

However, consulting various load data sources, I get some strangely conflicting data (all of these are for H380):
  • Hodgdon Landing | Hodgdon tells me to start at 44 (2169 fps), with a 47 grain max achieving 2461 fps (sierra bullet @.311")
  • These same figures are in a 2003 Lee manual
  • Hornady (11th Ed) tells me to start at 38, with 44.4 grain max achieving ~2600 fps (hornady bullet @.312")
  • A 1964 Speer manual gives the range of 41-45 grains with the max achieving 2606 fps (speer bullet @.311")
  • A 1967 Lyman manual give the range as 47-52 with the max @ 2695 fps (bullet not specified)
All of these are 25-26" barrels and none provide any pressure figures.

I'm surprised to see min loads that are higher than another source's min load, but I'm most surprised to see the velocity variation.

I'm also surprised to read that the 7.7 Japanese is clone of the 303 British, and the Arisaka is stronger than the SMLE, but that published loads for the 303 British are heavier than 7.7 loads. I'm not looking to push the limits on this rifle, but I'm trying to gauge how careful I must be.

Any suggestions on where I might want to start? Thanks for any input you might have for me.

CAUTION: This post discusses loads which while published, may no longer be valid with current components. Neither the writer, The Shooter's Forum, nor the staff of The Shooter's Forum assume any liability for damage or injury resulting from using this information. DO NOT ATTEMPT TO DUPLICATE THE DESCRIBED LOADS without first working them up from a published safe starting level charge while watching for pressure signs. If you don't know how to do that, don't try.
 

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The Shadow (Moderator)
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Several things are at play here.
#1) all of those sources are extremely old. Despite sharing the same names on the bottles of powder, they are not the same product. Also a good example of lot variations.
#2) Those loads(if actually pressure tested) were done so with Copper Crushers. Crushers are very well known to be inaccurate at the pressure levels operating in.
#3) I suggest investing in some current manuals. But some quick online sources include:
www.hodgdonreloading.com
www.nosler.com

Cheers
 
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How much H-380 fits in the case? Many times the old manuals are different just by case capacity differences. Fill a case to mid shoulder and weigh that charge. It's probably going to be right around 42-45 grains. If more than that, switch to a slower powder. 100% loading density solves a lot of problems that takes a long time to chase down. If the case only holds 45 grains, the 'max' is set for you.
 

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Discussion Starter · #4 ·
Several things are at play here.
#1) all of those sources are extremely old. Despite sharing the same names on the bottles of powder, they are not the same product. Also a good example of lot variations.
#2) Those loads(if actually pressure tested) were done so with Copper Crushers. Crushers are very well known to be inaccurate at the pressure levels operating in.
#3) I suggest investing in some current manuals. But some quick online sources include:
www.hodgdonreloading.com
www.nosler.com

Cheers
The Hornady (11 edition purchased through app) and Hodgdon (on public website linked above) data are current. I started looking at other, older data to try to make sense of the discrepancy. I don't believe that nosler makes a bullet in .311" or .312" so I doubt they will have any data.
 

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Discussion Starter · #5 ·
How much H-380 fits in the case? Many times the old manuals are different just by case capacity differences. Fill a case to mid shoulder and weigh that charge. It's probably going to be right around 42-45 grains. If more than that, switch to a slower powder. 100% loading density solves a lot of problems that takes a long time to chase down. If the case only holds 45 grains, the 'max' is set for you.
Thanks good idea. Probably an appropriate check, because this batch will be in PPU cases, and I suspect most of the data out there is with Norma cases. I'll see what I find.
 

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The Shadow (Moderator)
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Yes, Hornady #11 is current as is the Hodgdon online you referenced.... The greater point to not loose sight of, is the mistake of referencing obsolete data; for powders today which aren't the same.

Cheers
 
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The Hog Whisperer (Administrator)
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Yeah don't put too much faith in decades-old data, unless that's all you can get.

Case capacity is the thing that will ultimately make your powder choice for you. Compare it to other .30 cal cartridges of similar size. Quickload shows it as a touch more capacity than the .308 Win or .303 British, and a bit less than the 7.62x54 Russian. Your brass may vary from that, a bit.

Good luck.
 

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Another possibility is that the much older data with lower charge weights was developed using reformed military .30-06 brass, rather than the more thinly walled commercial cases. Data published 19 years after cessation of hostilities might ALSO have been developed in 7.7x58 mm Japanese military cases, scrapped from surplus loaded Japanese ammo.

Beyond common bore diameters, I'm not sure I see the similarities between the 7.7 Arisaka and the .303 Enfield. The Enfield round is rimmed, while the Arisaka has base and rim diameters more similar to the rimless .30-06. If memory serves, 7.7x58 can be made by running well-lube a .30-06 case up into a 7.7x58 sizing die, cutting the excess length off and fire-forming.

The Arisaka action is noteworthy for its strength which is indeed a nice safety margin. but any action can be blown. This is where a chronograph can be your best friend.
 

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Discussion Starter · #9 ·
I got 52.0 grains at the top of the shoulder and 49.3 on the bottom.

I tend to think that the Hodgon data, which specs a Sierra bullet (.311" like my Speers) is probably a better bet for me than the Hornady data (specs the .312" interlock). But given differences in components (brass, primers, and bullet make) and my low-velocity goal, I'll lean to the low side.

Therefore, I'm thinking of starting at 43 grains, which would be less than than the Hodgon min but only 1.4 grains less than the Hornady max.

Thoughts?

Sent from my SM-G960U using Tapatalk
 

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Discussion Starter · #10 ·
Beyond common bore diameters, I'm not sure I see the similarities between the 7.7 Arisaka and the .303 Enfield. The Enfield round is rimmed, while the Arisaka has base and rim diameters more similar to the rimless .30-06. If memory serves, 7.7x58 can be made by running well-lube a .30-06 case up into a 7.7x58 sizing die, cutting the excess length off and fire-forming.
My late grandfather formed cases from 30-06 brass for this rifle.

My grandmother's cousin brought it back from WWII and gave it to him. Tom passed last year: Thomas V. McNamara Obituary (1922 - 2021) Kalamazoo Gazette

I understand that the 303 Brit is a very different design, but I've read that the Japanese goal was to clone the ballistics.

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My Dad formed almost everything from Military 06 brass, including the 7.7 Jap. It was a hard chore in some cases. 6mm/.244 Remington, 7 and 8 Mauser. Even 270 and 25-06 had a failure rate. By the time I heavily got into reloading, brass was plentiful and cheap.

Good luck in your endeavor. I checked my Lyman 50th and no data. Neither does the 48th...BUT my Lyman 44th does have data. If you would like, I can PM you that info. Not sure how helpful as it is from 1967. :D

Edited: I sent you a PM.
 

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I understand that the 303 Brit is a very different design, but I've read that the Japanese goal was to clone the ballistics.
<slapping forehead> I should have realized that's where you were going with that sentence. Sorry.

I'm VERY sympathetic to the "failure rate" when converting '06 brass to other calibers, especially when having to neck down to a smaller bullet diameter. Usually, if the desired bore diameter is at all close to .308" (less than .010" or so), and difference in case length is less than 5 mm, it's no big deal. At .311", it's difficult to be closer on bore diameter. For SOME reason 6 mm is just too much, because I usually end up having to slightly ream the neck for 8x57 mm.
 

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Jsmyers,

Data from 1964 is very likely to be off because Hodgdon dealt only in surplus powders back then, AFAIK. So the H380 they had then would have been repackaged military surplus bulk grade WC852. That particular powder is known for wide lot burn rate variation in the bulk grade. For example, even though it is a spherical propellant designed for military 30-06 ball ammunition, one lot in 1972 had to be loaded several grains higher than the usual to achieve the standard velocity for 150-grain bullets, producing too much gas port pressure to qualify it for use in the M! Garand, and so it was segregated for use only in the M60 machinegun, which was OK with it.

On this powder burn rate chart, you see WC 852 (fast) and WC 852 (slow) in positions 203 and 226. Both would have been labeled H380 if bought from Hodgdon in the early '60s.

In modern times, Hodgdon now sources non-military lots of this powder but gets it put into canister grade rather than using the bulk grade as is. Canister grade starts out as bulk grade, but its burn rate is measured and then adjusted to within ±3% of a specified value for the powder type by blending it with held-back past lots of the same powder that came out of the factory with either a faster or a slower burn rate than the new lot has, depending on which direction the new lot's burn rate needs to be adjusted in to bring it into spec. The powder is then consistent enough for databook load recipes not to be dramatically different in performance, though it means the powder you buy is not 100% fresh powder but is a mix of powder ages. This is a cause of some powders starting to break down prematurely.
 

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I'm learning a lot today, thanks unclenick. Learned about squaring cartridge bases. Then I learned you don't have to be a jerk to shoot a pistol. All in all, a good day so far. :geek:
 

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Any form of jerking spoils pistol accuracy even more dramatically than it does rifle accuracy. ;)
 

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Discussion Starter · #17 ·
Thanks for the history on H380 unclenick!

I got 52.0 grains at the top of the shoulder and 49.3 on the bottom.
...
Therefore, I'm thinking of starting at 43 grains, which would be less than than the Hodgon min but only 1.4 grains less than the Hornady max
I also measured the mass of water that would fit in a fired PPU case with the bullet seated. 57 grains. That corresponds to 53.5 to 55 grains of H380, depending on the density which g/cc figure I use (.967 or .938).

This puts 43 gr just a touch over 80% load density. Seems good to me.

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The Hog Whisperer (Administrator)
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So basically you're right at .308 Win case capacity.... that will be handy to know if you come up with some powders that you can't find data for. Use starting loads for the .308 Win as needed, and go from there. Shape of the case (taper / rim) will make little difference in the end.

Good luck.
 

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The Shadow (Moderator)
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at corresponds to 53.5 to 55 grains of H380, depending on the density which g/cc figure I use (.967 or .938).
I would personally measure your own VMD, and not go on faith from someone else. In my Volume sticky, you can see how to do it if you need help. I've found my own lots to be notably different at times, from printed data.

Cheers
 

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^^^That's a good recommendation. Before Western was absorbed by Hodgdon, they listed bulk density and its lot-to-lot tolerance for their powders. It ranged from ±2.2% to ±5.6%. That's an 11.2% extreme spread in the latter case. The only reason Lee gets away with VMDs for figuring loads is they recommend mild loads in their data, creating plenty of safety room.
 
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