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WARNING!

This article contains information on modifications of reloading ammunition that requires some reloading experience.  This technique works for our weapons and reloads.  As we have no control over others shooting needs, techniques or materials, we cannot assume any responsibility if you decide to use the technique on loads and/or rifles of your own.  As always, reloading ammunition is a serious undertaking and needs to be carefully examined at each step to make sure all safety precautions and inspections are adhered to.  

I purchased a decent quality Japanese Type 99 rifle over 2 years ago.  I am somewhat ashamed to say that I had not done anything with it until just recently except look down the bore a couple of times.  At the time that I got it, the ammo (7.7x 58mm) was not that common (still isn’t) in either the loaded or unloaded form.  I kinda just shrugged, put the rifle back in its case and went on my merry way and proceeded on the road of a bad case of mil-surptitious.

Then Grafs started selling the Frontier 7.7 brass.  It’s stamped with 7.7 and is, of course, boxer primed.  So I picked a bag up…and once again put it all back into storage for another year.

So that brings me to now.  I finally took out the rifle to look it over and determine some markings on it.  Turns out that it appears to be a GI bring back, as there are no import markings on the rifle.  It was missing the dust cover, probably never had the monopod on it and didn’t have the side “wings” on the rear sight either, although it does have the mounting points for them.  I picked up a new made replacement dust cover from Sportsmans Guide just to put it on and see what it felt like.  Doesn’t really do much to the rifle, other than make you wish you had 3 hands to put the bolt/dust cover back into the receiver.  You have to make sure that the bolt goes in correctly at the same time making sure the cover slides along the grooves in the receiver.

According to sources, my particular rifle was made in the Nagoya Arsenal, the series number is 6 and the serial number places it very near the start of that series of nearly 100,000 rifles.  The mum has been ground down, but you can see some residual marks where it used to be.  Over all the quality of my rifle is fairly decent, the bluing is quite good and the wood (as most mil surps have) is pretty beat up and dinged.  As I mentioned, I didn’t do anything other than clean the bore to it.

So now the ammo issue.  I could purchase the new made 7.7 Japanese ammo that is currently available from Hornady.  But at more than $20 a box of 20, well, why?  I’ve got the reloading equipment needed, so I bought the dies needed from Lee. 

Now, in the mean time, I was doing some research on cartridge conversions for the 7.7 Japanese.  Turns out that time and again, it came down to the fact that you COULD easily make brass that would work in the Type 77 without any major complications or costs.  There are two cartridges that people where using to convert, the 30-06 and the 8mm Mauser (7.92 x57mm).  I decided to proceed to a do it yourself project of running a comparison of the three types of brass and how they shoot.  I figured that some would want to save some money and buy the cheaper 8mm brass (vs. the 7.7 brass) and there would be the real cheap guys that will use some left over 30-06 brass laying around their bench for a freebie conversion.

Right away you notice two things about the brass to be converted.  The first is that the 30-06 is WAY longer (on that note, it’s time to switch to inches….) at 2.494” in length.  A 7.7 Japanese is spec’d at 2.27” and a 8mm Mauser is 2.240”.  As you can see they are varied quite a bit in length.  Rim dimension wise they are closer, with the 30-06 rim at .473”, the 7.7 Japanese at .471” and the Mauser at .473” as well.  In the reading of what others have done, this minor dimensional difference does not make a difference.

Case conversion 30-06

I started out with once fired commercial brass, all with the R-P (Remington-Peters) head stamp.  I know they were all once fired, I stood there catching them as people ejected them from their rifles during sight in days at the range.  The first step is to pop the old primers out.  I use a universal decapper.  This way I do not have to worry about dirtying up my actual loading dies and secondly, it is just plain faster in terms of set up.  Finally, if I want to load Berdan primed brass (which I do in other calibers) I can remove the decapping pin from those dies and still be able to decap boxer primed brass in the same caliber. 

After I’ve popped the primers, I clean out the primer pockets because I want my cleaning solution to work the pocket as well.  I have several different primer pocket cleaners and reamers, but I still like the ease of use of the Lee pocket cleaner.  Unlike the brush style cleaners, I don’t have to worry about loose or bent bristles and I can practically watch TV at the same time as cleaning because the tool aligns itself to the pocket automatically.  After that I use a liquid wash to clean the entire case.   Read more about the liquid cleaning method, take a look at this previous article:

http://www.surplusrifle.com/shooting2005/berdanreloading/index.asp

I have a Lyman Universal decapper, most every reloading company makes one.  Additionally, I have a set of Lee’s “extra” shell holders for use in my two presses. 

The Lee primer pocket cleaner is a simple and inexpensive device that easily cleans small and larger primer pockets.

Before (figure 3) and after (figure 4) cleaning shots of a 30-06 primer pocket.

The 30-06 brass is way to long to just go right into the sizing die.  At first I was really gung ho to use my RCBS case trimmer to cut down the case, until I actually measured and saw for myself just how much brass would have to be removed.  Almost a good ¼” of brass has to be removed (.216” ).   I nearly decided not to try out the 30-06 brass, but then Mark dropped the idea of using a pipe cutter to trim off a majority of what needs to come off and then use the case trimmer to take off the last few thousandths.

To use the pipe cutter, just place the case in the device setting the wheel to cut less than the .216”, you can eyeball it really.  As you tighten down the cutter wheel, rotate the case once or twice.  As you do this, you will notice a groove form.  Go slow, a couple of turns of the case for each tightening of the wheel.  It only takes about a dozen or so rotations and the cut off piece will drop off.  Note that because of the design of the pipe cutter and the shoulder of the case, the cut will not be perfectly straight, but the case trimmer will square it up later.

A three dollar pipe cutter is an easy way to take of the majority of brass from the case length before finishing it up in a case trimmer. 

After a few a turns, a groove starts to develop.

Here, the cut piece is free of the case.

The final piece.  A very odd looking 30-06 case for sure.

After you have the rough trimming, you will need to use a case trimmer to take off the final few thousandths as well as square up the mouth of the case.

Once you have the case trimmed down once to the required 2.27” length, lube it and run it through the full length sizing die without the expander.  What will happen is that the case will stretch a bit, so you will have to trim it in the case trimmer one more time.  This time just a few turns will take off the extra length.  Once the case has been trimmed to the final length, you will need to chamfer and clean the mouth of the case.   After that you are ready to reload the case.

I use this neat little bench mounted device that chamfer and bevels the case in one tool with one pass.

Case conversion of 8mm Mauser:

Well, this is actually an easy one.  First, obtain some 8mm Mauser brass (I bought some from Midway USA).  Second, removed the expander from the 7.7mm die, lube the case and form the case.  Chamfer and debur the case as normal, check the length (I did not have to trim) and you are done and ready to load up the rounds.  Now why, do you ask, did I even bother with the 30-06 conversion or even buy the 7.7mm brass?  You have to realize that even though 8mm is more common then 7.7mm, it is not as cheap nor plentiful as 30-06.  Besides, this is a how to be cheap article…

Here is a look at the various brass and their stages.  You can do some side by side comparisons on length and what they look like.

Before I go into the reloading part of the ammo, let’s talk a bit on safety.  Obviously it would not be very healthy to either load a converted 30-06 brass case into an 30-06 rifle nor would it be very wise to load a converted 8mm case into a Mauser rifle.  How do you keep these converted cases apart?  Some people use a small file and run a cut line on the rim of the case.  I choose to diligently keep my brass separated by size and well labeled even inside their individual boxes.  And, of course, I make darn sure that while I am reloading I am working on only one case size at a time and all other caliber specific dies, tools, bullets and powders are put away.

One way of organizing your brass is to use individual plastic shoeboxes for each caliber to store (unloaded) brass.

The load work up:

I slugged the barrel of the Type 99.  The slug was a disheartening .314 in size and did not show much rifling at all.  I was pretty bummed.  The barrel wasn’t the best of barrels, there SEEMED to be a enough rifling left, but I had not done much in the way of indepth viewing of it until this article.  The exterior of the rifle, after all, was in a much better shape.  Nevertheless, I proceeded to see what would come of it.

I chose to use cast bullets of 20:1 lead:tin alloy, 185gr Lee mould # 90371, which they list for the 7.65 Argie, 7.7 Japanese and .303 British, which are all essentially equivalent in power.  Using the 20:1 alloy the actual weights averaged out to about 179gr.  A friend of mine cast these up for me as I actually don’t do any casting (yet).

Before loading, I lubed the bullets with SPG lube and placed a .30 cal gas check on the bullet, then ran it through a .311 Lee sizer.  The bullets came out exactly what I expected (and wanted) that is long and heavy.

I chose to run these bullets using our Surplusrifle.com Load (I normally call it the “SRc load”) which consists of 22gr of IMR 4198 topped with enough PSB shot buffer to fill the case to the base of the bullet (see our article:  http://www.surplusrifle.com/shooting/castfiller/index.asp).  I chose this load because I do not want and do not need a full power load and I have had great results using the same load in a variety of mid to large size calibers.  Prior to seating the bullet, I used the Lee universal case expanding die to slightly open the mouth of the case to accommodate the cast bullet.  After seating the bullet, I used the Lee 7.7mm factory crimp die to crimp the bullet into place.  So after loading 20 rounds of each of the brass case types, I headed off to the range. 

Our range was in the process of deer hunting sight in days, so I was not able to shoot as much as I wanted nor as far as I wanted before darkness set in.  Still, I got results that looked very promising.

25 yard target, 5 shot groups of each brass type.  Note:  the 30-06 brass was fired with the aiming point shifted to the center of the bullseye instead of “floating” the bullseye on the front sight.  I think that really they both would have grouped in the same place and spacing had the aim point been the same.

25 yards, 5 shots.  8mm converted brass.  In all cases, recoil was very light and the rifle was truly a pleasure to shoot.

Final shots of the day at 50 yards.  This is a mix of about 4 shots of each type of ammo that I quickly fired off before the range closed.  The one consequence of the light load is that the bullet impact is very low, typically 6 to 8 inches low at 50 yards, so at this point I had adjusted the ladder rear sight so that it raised my point of impact.

A comparison of unfired (loaded) and fired brass of the three types used.  You can see that the 8mm case really moved the shoulder forward upon firing.  From this point, these cases are fire formed to this rifle and really should only need to be neck sized to reload.

The final conclusion leads me to say that either of the two case conversions ought to work out just fine.  Obviously the 8mm is the easiest, but the 30-06 would be the cheapest.  I only worked up a light target load.  I have not read anything that seems to say that the converted brass could not be used for something heavier.  In the near future, the second test of this ammo will be tried out in conjunction with the S&K scout scope mount and then fired at 100 yards.  That ought to be the proof whether these rounds can hold their own.