Fireforming 6.5 Grendel

[chas442]

I am looking to reform 7.62x39 brass to 6.5 grendel. I've got a lot of 7.62x39 brass. I will be resizing using Lee dies. It appears grendel has less taper than 7.62. Looking for suggestions.
I have hornady 123 gr 6.5. What is a good way to fireform after resizing?

TIA

 

[highlander 5]

I've tried reforming 7.63x39 into 6.5 grendel with little success usually ended up with a crushed/collapsed case. I'm using RCBS dies.

 

[dh1633pm]

Best way to start is with one. Always had better luck going bigger than going smaller.

 

[adcoch1]

I used Hornady case lube to neck them down, then a starting load charge and viola! Fireformed cases. I like having a batch of grendel brass with large rifle primers too. Maybe not as accurate as small primer brass, but I have lots of LRP's!

 

[Varminterror]

I guess I’ve been blessed. Neck down, leave a tight “kiss” fit, only sizing enough to allow the action to close itself (assuming a gasser), and fireform. Lube the shoulders well, and annealing does help prevent splits. You’ll typically end up with under capacity brass, and the wrong primer size, so load data doesn’t translate and brass doesn’t last long - AND you may need or want to turn necks since the x39 brass is generally thicker than Grendel.... but it’s really not so complicated as some folks make it out to be.

 

[cfullgraf]

I'm no sure if the shoulder angle differs from 7x39 and 6.5 Grendel, but I form 22x6.8 from 6.8 SPC cases. I use a 6.8 SPC bushing sizing die and change bushings to reduce the diameter of the neck in small increments. It works the brass less for each pass through the sizing die.

You may still need to turn the neck of the case as it gets thicker as the diameter decreases.

 

[chas442]

I appreciate all your comments. 6.5 grendel brass is unavailable. I am going to fireform the 7.62x39 cases that I have so I have something to work with until grendel brass starts showing up. I realize that most not all of my 7.62x39 has large primer pockets. I have imr 4895 and trailboss among others. Where should my loads start at. I also have 2400 that was supposed to have been pulled down from 7.62x39 ammo.

TIA

 

[dh1633pm]

For experiments I use about 8 grains of AA No 9. Fill with cream of wheat, the plug the end with a toilet paper square. Fire into something like a bunch of rags outside or take to the range. Test one before going into production to see how it goes. Be careful.

 

[rdnktrkr]

Check with some once fired brass places, I just purchased 500 pcs from a local place

 

[chas442]

Will 8 grs AA9 develop enough pressure to actually fireform the case? In the past I have fireformed cases by using about 5 % less than the minimum list load spec.