New Powders for the Arisaka
Welcome to the second part to a series that will probably last the rest of my life considering how slow I am to put out new information. I started the first article out with attempting to find a load that would well in short barreled Arisaka rifles. I will continue that trend but I also just want to add load data for powders that aren’t listed in the manuals for 7.7x58.
Our first contestant, Hodgdons LeveRevolution, was a powder that I thought might be interesting try, and to see if I could get a more performance, like they claim for the lever action cartridges. My thought process for finding a starting load was probably more complicated than it needed to be, but it seemed to work well enough. I started by looking up listed powders for the 7.7x58 as well as the 303 British. For those unfamiliar with 7.7x58, the Japanese copied the 303 British performance and ballistics so closely, that 7.7x58 is essentially a rimless 303 British. Therefore, one can use the same load data almost interchangeably. Obviously, do so at your own risk and doublecheck your data! I started by finding data for loads with H-380. On the powder burn rate chart, H-380 is number 114, just under LVR at 113. The max load for H-380 with 180 grain bullets, was listed at 42 grains and averaging 2276 fps. Based on this information, I started my first set of 5 at 40 grains and worked up in half grain increments to 42 grains of LVR. The following is what I managed to collect from my testing:
The first series at 40 grains failed to collect data after the first shot. I will need to reshoot that and see what speeds I get. As for the following series, my takeaway is less might equal more in this case. Series 3 at 40.5 grains is the best looking group in terms of consistency. Series 4 through 6 were pretty wild, with the standard deviation being the worst in series 4 at 41 grains, with a standard deviation at 172 fps. Frankly, that’s terrible. Series 5 wasn’t far behind at 168 fps of SD, and it started to drop a bit with series 6 at 93.9 fps of SD. There were no pressure signs with any of the loadings so perhaps pushing past 42 grains might be beneficial to see if there is an accuracy node further up. It should be noted that recoil for my particular gun, was substantial at the 41.5 and 42 grains loadings, even with a gel recoil pad. My conclusions for this test are, that 40 to 40.5 grains might warrant further testing. The consistency of that group looks promising, so I will make a finer ladder test of 0.1 grain increments. It also would seem that I may be running into limitations of the barrel length. As testing had been done with a 19 inch barrel. As per other tests, I did not make any attempt at accuracy as this is just to establish a base on which to build further.
Thank you all for reading and I hope to have more articles out in the near future. My life has gotten very busy in the last couple years to the point I neglected the website. I was trying to shoot videos that would accompany every article I wrote, but I just don’t think that is feasible right now unfortunately. Writing is a lot easier and faster so that is what I will focus on for foreseeable future. I hope to one day start a video channel of some sort to accompany the writeups. However, I do thank you for looking through the site and reading the few articles I have so far, and I hope you find some useful information.