Reloading Imperial Japanese Rifle Cartridges Part I – Reloading 6.5Mm Japanese (Updated 13 September 2009) Shannon M

Reloading Imperial Japanese Rifle Cartridges Part I – Reloading 6.5mm Japanese (Updated 13 September 2009) Shannon M. Zeigler

Author’s Note: This is a special edition of my second revision of an article originally published in Banzai, The Japanese Militaria Collector’s Bulletin,2003 Issue 230, pp 127-30. The article is divided into two parts. Part I: Reloading the Japanese 6.5x50mm Semi-Rimmed (SR) Cartridge and Part II Reloading the 7.7x58mm Cartridge.

Since my first article was published, the availability of less expensive factory ammunition offers greater cartridge choice and pricing to the casual shooter. A 20 round box of factory ammunition sells from $17.99 for P.C.I. to $38.59 for Norma (Table 1.). Reloading, however, offers the shooter per shot cost savings, custom loads, improved accuracy, and personal satisfaction1.

The intent of this article is to present some of my reloading procedures for 6.5 x 50mm SR (semi-rimmed). Hereafter, referred to as the 6.5mm. I will briefly address the history of these cartridges and technical specifications, but will not cover the 161 grain round nose 6.5mm Type 30 cartridge. This article assumes the reader has a basic knowledge of reloading. There are numerous reloading manuals and websites that can address the more detailed aspects of reloading. I assume no liability and strongly encourage users to reference current reloading publications and practice all basic reloading safety. I feel safe using these methods but as I say, “your loads, your life, your choice”.

The 6.5mm Japanese Cartridge (6.5 x 50mm Semi-Rimmed). A great variety of Arisaka rifles and carbines are chambered in 6.5mm Japanese making it a choice cartridge to reload. I prefer shooting 6.5mm rifles over the 7.7mm because of its superior accuracy, mild recoil, and the stock pull length. A Type 38 is about one inch longer than a Type 99 Short Rifle.

Brass cases can be found in two basic varieties; factory formed (Norma, Prvi Partizan) or you can re-form your own. Graf and Sons sells 100 factory formed Norma and Prvi Partizan (PPU) unprimed brass for $115.85 and $41.99, respectively. .35 Remington (.35 REM), .243 Winchester (WIN), .308 Winchester (WIN) and .220 Swift are also sources to form 6.5mm cases. Reforming .243 WIN, .308 WIN and .220 Swift are not addressed in this article. Conversion of .220 Swift to 6.5mm is an involved process, and is the topic of an addendum for the adventurous reloader2. One advantage of using .220 Swift is a semi- rimmed case like the original 6.5mm. Graf and Sons lists 50 unprimed Winchester .35 REM cases for $26.59. This is currently more expensive than factory PPU 6.5mm, but if you buy once-fired or find range brass the cost is minimized. One advantage to using .35 REM is that the case head diameter is slightly larger than factory 6.5mm Norma cases (I have not checked PPU). Norma brass uses SAMMI specification and, when fired in the typically oversized Arisaka chambers, has a tendency to bulge. According to the Sierra Rifle Reloading Manual, 3rd Edition (Sierra), 6.5mm has a head diameter of .447 inch compared to .35 REM’s .4574 inch diameter. .35 REM’s .0104 inch larger head diameter aids in reducing case bulging and produces more consistency and extends case life.

1I can reload a box of 6.5mm or 7.7mm for approximately $6.50- cost estimate excludes once-fired brass and time. 2Vis35, (JAN 09) Forming 6.5mm Japanese Cases from .220 Swift. Forming .35 REM into 6.5mm is relatively simple and straightforward. For these reasons .35 REM is one of my favorite sources to form 6.5mm cases. On a side note, Swedish Mauser stripper clips work well with 6.5mm cartridges, and saves using collectable and expensive original Japanese clips.

6.5mm formed from .35 Remington. .35 REM must initially be sized in a .308 WIN resizer die. The purpose of running the .35 REM case through a .308 WIN resizer die is to reduce the case mouth enough to allow the 6.5mm resizing die to effectively resize the case. Once you have resized your brass in the .308 WIN resizer die your .35 REM is ready to be resized in the 6.5mm resizing die. Resize as you would any standard cartridge - don’t forget to lubricate your cases! .35 REM is shorter than 6.5mm specifications so it is not necessary to trim-to-length after final sizing – another advantage. When your cases do stretch, Sierra recommends a trim-to-length of 1.974 inches and an overall maximum length of 2.940 inches. Original 6.5mm is semi-rimmed whereas .35 REM is rimless, but I had no problems using .35 REM cases in any of the many 6.5mm Arisakas I have fired.

One problem I occasionally encounter is resistance upon closing the bolt on a freshly converted .35 REM (6.5mm) case. The resistance is caused by the shoulder not being perfectly formed. I give the bolt an extra push and upon successful closing, fire the case. After the case has been fire formed it will chamber with no problem. Do not fire unless you are certain the bolt is completely closed.

6.5mm Specifications. According to Frank Allan’s seminal book, The Type 38 Rifle, original Type 38 Cartridges were issued in three configurations; the 139 grain flat base full metal jacket (FMJ) bullet Type 38 Cartridge, the 138 grain FMJ Modified Type 38 Cartridge, each with an average velocity of 2500 feet per second (fps), and the “reduced charge” 139 grain G load with an average velocity of 2360 fps. The Modified Type 38 ball differs from the Type 38 Cartridge in shape and is weighted in the rear to induce tumbling on impact. I recently pulled and measured three original bullets, two cupronickel jacket and one copper jacket bullets. The cupronickel bullets were taken from demilitarized cartridges and contained no powder. The cupronickel flat base bullets weighted 138 grains and measured .261 inch diameter. The copper jacket cartridge contained 30.5 grains of square flake powder behind a 136.6 grain .2615 inch diameter flat base bullet. According to Mr. Allan’s research the Type 38’s nominal bore diameter ranged from 6.5mm (.256 inch) to 6.78mm (.267 inch) with lands of 6.55mm (.258 inch). To give some perspective on diameter variance I have listed bore diameter slugs from Mike Rockhill’s and my collections. See Table 2 at the end of this article.

6.5mm Loads. I prefer bullet weights between 120 and 142 grains because they are closest to military specification (MILSPEC). My favorites, for their accuracy, are the .264 inch 140 grain match bullets offered by companies like Hornady and Sierra. PPU offers .264 dia. 139 grain FMJ and SPBT, but I have no data on their performance at the time of this article. There is numerous load and bullet weight data available on the internet and popular reloading manuals. I have had good results with medium burning powders such as IMR 3031 and 4895. My favorite is 31.5 grains of IMR 3031 behind a 140 grain match bullet. I have had outstanding accuracy with that load in my Type 38 Rifles, and it duplicates the original Type 38 Cartridge. Refer to Table 3 at the end of this article for selected load data.

2 Conclusion. Reloading the 6.5mm cartridge can provide a relatively inexpensive source of ammunition, hours of reloading pleasure, and load options not available to the average shooter. I am grateful to Frank Allan and Mike Rockhill for their comments and assistance with writing this article - Thanks. Please send questions or comments to my email listed below.

Table 1. Component and Ammunition Cost: www.grafs.com/ 17 December 2008 Caliber Make P.C.I. Hornady Norma Prvi Partizan 6.5mm Ammo per box 20 rounds $17.99 $23.99 $38.59 Unprimed Cases per 100 $115.85 $41.99 Bullets per 100 Prices range on average from $13.00 to $27.00 per 100

NOTE: Most catalog/on-line reloading dealers (Grafs, Midway, etc…) will offer dealer pricing to C&R FFL holders. Contact dealer in question for specific instructions.

Table 2. 6.5mm Bore Diameter Samples Rifle/ Carbine Arsenal Series Serial Bore Groove Number Diameter Diameter Comments T38 Carbine Nagoya 4 61342 .257 .267 140/142 SMK shot well Type 38 Kokura 26 22299 .255 .264 Type 38 Tokyo none 1.8 mil .255 .267 Hdy 140 SP shot well Type 38 Kokura 23 34836 .257 .267 Type 38 Nagoya 28 89566 .257 .268 Table 3. Select 6.5mm Reloading Data Shots Type Bullet Bullet Average Extreme Standard in 38 Rifle Powder Load Weight Type Velocity Spread Deviation String Remarks Tokyo Kynoch unk 161 RN FMJ 2122 201 142.0 2 Original 1916 date Kynoch T30 Tokyo IMR 3031 28.2 140 SP 2213 53 15.4 8 2 did not record on chrony Tokyo Chinese unk FMJ 2233 56.9 31.55 2 Original Chinese 6.5mm S:26 IMR 3031 28.0 140 SMK 2282 40 12.3 10 ≈ Mil Spec Reduced G Load S:26 IMR 4064 30.2 140 SMK 2399 187 54.7 10 Reduced G Load Japanese-3 stake primer/pink Tokyo Factory unk FMJ FB 2418 70.57 29.2 5 band/cupronickle Tokyo IMR 4064 33.0 140 SP 2443 68 22.6 10 reformed .35 REM S:26 IMR 4895 33.0 140 SMK 2516 64 18.6 10 ≈ Mil Spec Type 38 Rifle Loads S:26 IMR 3031 31.5 140 Hdy Mtch 2552 43 17.7 4 ≈ Mil Spec Type 38 Rifle Loads

Bibliography:

Allan, Frank and Macy, Harold. The Type 38 Arisaka. Palm Coast: Francis C. Allan, 2007.

Graf & Sons website, http://www.grafs.com/, 17 December 2008.

Gunboards.com website, www.gunboards.com, 30 December 2008.