6.5x50 Jap Case forming

Jeremy2171

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Over the next few days I will make a post with pics on how to properly convert brass for the 6.5 jap.

Why convert?? All modern ammo for the 6.5 Jap is based off SAAMI specs...these were created postwar long after the 6.5 jap was out of production. Those of you with 6.5 japs that shoot norma or graf/hornady brass in them notice there is a "bulge" on one side near the head. This is due to the cases being made to SAAMI specs which on the small side compared to japanese chambers which can be larger due to wartime easing of the specs or even them being slightly oversize to allow for dirt ..mud etc conditions.

Is it really an issue? Not really....but my OCD really bothers me when I look at my fired Grafs cases and that huge bulge is there right in the open.... I'm not on Tarawa or some other island and need my rifle to extract with a chamber full of coral dust....

Will the bulges affect your case life...yes? By how much?? That I don't know....BUT I do know that your cases are no longer concentric as they will have a distinct "top" and "bottom" after the bulge is formed. Not a big deal if you just want to casually load and shoot them...but I also prefer to compete with them and even hunt if time allows it...

My goal was to make a better fitting case....it's been done before on the web and it'll be done again... I'm just going to post my experience with making this brass over the last 10-15 years or so.

So if you are interested in learning how to do this....stay tuned....
 
Ok did some picture taking today....

Here is what we are trying to avoid... the cases on the left and right are Graf and Norma 6.5 Jap cases... note the "bulge" ~ 1/4" up from the base. ALL new commercial 6.5 jap brass does this.

What we are going to do is make brass that doesn't bulge...like the case in the middle. All three cases were fired from the same Arisaka....notice no bulging on the middle case??

IMG_20170101_134653859_HDR_zpsukxpseuq.jpg



The only difficult thing you will need is a swage die. I got mine a long time ago from a fellow jap shooter. If you have any machinist friends or skill..its not hard to make. Thread a piece of steel to fit standard presses... at the bottom make a hole @ .458 and polish it. Then the rest of the "die" is back bored as you only need 1/4" of swage area.

Also you can make a dummy "flat" shell plate to allow the case to touch the die bottom or you can use a small socket on a normal case holder as a ram.

IMG_20170101_135026731_zpslp841kwc.jpg


IMG_20170101_135011454_HDR_zpsg89holma.jpg


Once you have the swage die we can continue with this little project....
 
Ok...our parent case choices for this project are... .243/.260/.308

.243 and .308 are common and easy to find and .260 is just perfect but it's more expensive and harder to find usually.

The cases are all from the same parent case of .308 with the only real difference in the shoulder/neck area. For conversion to 6.5x50 they are rated as follows.

.243 -great
.260 -perfect
.308 -good

.260 can't get any better... swage it and size it..
.243 almost as good as .260..just be careful expanding the neck to .264.
.308 usable but you WILL have to get a neck reamer as you are squeezing a .308 neck down to a .264 size and the neck brass gets too thick to chamber without reaming/turning.

Here is the simple case forming procedure using a once fired .243 case.

Set up your swage die so as the case goes thru it the brass hits the bottom near the top of the stroke so you can get full leverage on your press... I HIGHLY recommend a STRONG "O" shape press as you will need to grunt a little to get the last 1/4" of the case thru the die.

Take the case and lube the body using a good lube... NOT SPRAY LUBE!

Start the case up into the die....
IMG_20170101_135406834_HDR_zpsahllp049.jpg


No matter what you will need to use a small socket (or similar) to push the case head thru the swage area of the die.

Here you can see the socket getting the brass past the swage.
IMG_20170101_135510847_HDR_zpshhftzhuv.jpg


Here is the base of the .243 after going thru the swage....notice the "ring" in the headstamp...if you had a smaller socket it would almost perfectly "line out" the now no longer ".243 win" headstamp.

IMG_20170101_135246881_HDR_zps6w3ikdnc.jpg


Side view of the swaged .243 case....notice it has been reduced in size starting at the shoulder all the way to the base...this is also a bonus as it is less brass to move when we run it thru the size die.

IMG_20170101_140109911_HDR_zpsm5x0e85s.jpg
 
Great!! Now we have a case swaged to the proper head size of the 6.5 jap case.

Set up your 6.5 Jap size die according the instructions (mine are RCBS)

Now ensuring you have no case lube in the shoulder or neck area (INSIDE the neck is needed as we are expanding from .243 to .264) on the case and that your die is clean from excess lube....start it into the size die..

IMG_20170101_140745955_zpsrytv9owl.jpg

After you have gone 1/3 to 1/2 the case length...STOP and back it down a little... you will need to add some lube to part that has just been reduced in size..

IMG_20170101_140831972_zpspdxfllfo.jpg


Continue to fully size the case to full press movement and ensure you "cam over" at the end....if you need to stop and spread the lube again...do so .

Now remove the case and viola... you are ALMOST done... you have a case that is now a 6.5 jap with the exception of overall length....

Unsized .243 on the left... freshly converted .243 to 6.5 in middle and WW2 6.5 on the right..

IMG_20170101_141610821_zpsqxhf9rtc.jpg


Thickness of the .243 compared with the converted .243....thats the same diameter on both case...when done your new 6.5 cases will be ~.459 at the rim and head. Now all you need to do is trim to size and load.

IMG_20170101_140234521_HDR_zpskfvdj2ej.jpg


I do urge you to anneal the necks either after forming or the first firing. We did work harden that area so annealing will extend case life.
 
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