How do you expand up your 6.5x284 brass to 7mm?

[falconpilot]

Guys,

Recently been expanding some new brass. I've been using a K&M tapered expanded Mandela(.284) to expand up my 6.5x284 brass. I lube the neck well, run the Mandela into the case, pull most way out, rotate the brass, run into again, pull out, rotate brass another third of a turn, and expand one last time. I've found that this seems to prevent donuts, but I'm finding that my cases run out is excessive. Been thinking of going to two steps, using a .270 Mandela first, then go with the 7mm.

How are you guys doing it and avoiding the excessive run out??

Jim

 

[LHSmith]

Al Nyhus recommends to anneal new cases. Check out the thread on BRC titled "Necking up the 30BR." in the General Forum.

 

[Baron]

Jim,
Why not just blow it out using about 12 grains of Unique and Cream of Wheat?
Baron

 

[Kenny474]

I would try the .270 mandrel and then go to .284. I know that when necking down, doing so in steps helps concentricity, so I would think expanding would be the same way.

I did a bunch of .280 brass that I made into 30-06 and just used my Lee FL die. The expander in the Lee dies did an awesome job and didn't hurt concentricity all that much.

Lee's expander is very gently tapered and will slowly expand the neck to full diameter. I personally like Lee's expanders more than most others as they seem to produce straighter cases than the other dies I have used.

 

[AlanPF]

...How are you guys doing it and avoiding the excessive run out??

Jim

Jim,

I am using the same K & M expander for a 284 Shehane, and while I can't say I've checked the pre-fired runout, it is very good after the first firing and improves further after the second. I have been using 6.5-284 Lapua brass in a 6.5mm for many years and the runout in the new brass has always been disappointingly high, and I wouldn't expect an expander mandrel, even with the one-third rotations, to fix it, because there is no firm lateral support for the shoulder as the mandrel goes into the neck. So FWIW my advice is to wait till after the first firing before you measure runout - otherwise you may be disappointed.

Alan

 

[Rustystud]

I have done litterally 1000s of 6.5 X .284 to straight .284.

If not done correctly you may get the dreaded donuts.

Charles Ballard in his article on this web site states to use a tapered expander instead of ball expander.

I suggets you buy or make a tapered expander die like Sinclair sells and a Full length Sizing die like the one made by Redding.

For a no neck turn .284 Winchester The sizing die that I uses a .309 neck.

With Lapua Brass the loaded round will be .3125

The neck diameter of my reamer is .3165.

Another hint the .284 loads of yesteryear were designed for the Winchester model 88. The necks were .320 -.322 OD. The bullets were shorter than the bullets made today. The throats also need to be opened up so the bullets bearing surface can be seated out to the neck shoulder junction of the case. If you seat the bullets to deeply you will have issues with fliers. Bullets seated to this length will not fit the conventional SA magazine lengths. Short Action repeaters will require modification.

Nat Lambeth

 

[falconpilot]

Great info guys.. Keep it coming...something else I've forgot to mention. I use a Foster press..since the die/expand " floats", this could be leading to a little misalignment resulting in the runout. Also, exactly how you load cream of wheat? Wax??

 

[Baron]

Jim,
I use COW to form 6mm Dasher and .300 ATLAS (Improved WBY) cases. In the Dasher I use 9.0 gr. of Unique and 14.0 gr. in the ATLAS. Start with 11.0 gr. of Unique, fill the case with COW. Thump the side of the case until the COW settles at the NK/Shoulder junction. Take a ¼ of a sheet of toilet paper, fold it twice and roll it between your finger tips into a cylinder. Stick it in the case mouth and use a ¼” Allen Wrench to pack it down tight. Lightly spray the case with Hornady One Shot or WD-40 and fire it. The Case should now be 7mm. If you are running a tight neck expand it and turn the neck. Using COW the case necks will be as concentric as your chamber. I use Neil Jones Custom Bushing dies for both the Dasher and ATLAS and have zero run out!
Baron

 

[TonyR]

Jim.
I've done hundreds of Shehane cases by necking up in three steps with expander mandrels, the last being the mandrel for the neck turner. I then turn them, anneal them and shoot them. Since I am doing the Shehane, I have to fireform no matter what else I do. I anneal because I found that the first firing straightens the necks if I anneal and may not if I don't. I did the first 500 cases in one batch and used a developed load to fireform in 600 yard matches. Knowing what I know now, I would use the cream of wheat method after annealing the 6.5X284 cases if I was doing a no-turn neck, either straight 284 or Shehane. I plan to expand, turn, anneal and then cream of wheat my next set of Shehane cases because I won't be doing enough to work up a match fireforming load like I did the first time and I think the cream of wheat method will save on barrel and components. I have had a different experience with donuts. I have found them in every new case I have neckturned. Some are worse than others, but I have not been able to use a K&M turning mandrel in a case expanded with the K&M expander even in my 6mmBR without first cleaning out the inside of the neck in some way.

 

[1000yardstare]

If you use COW carefully read the label. Some brands contain table salt to extend shelf life.

 

[Kenny474]

I hear a lot about using a tapered expander and see many people spend a lot of dough on different brands of expanders and such, and even I have a K&M. But if you just look at the design of the Easy Expander that is in the Lee Full Length sizing dies, you will see it's a very well designed tapered expander, and it also costs a lot less than many of the expanders on the market as well.

You could buy a Lee universal decapping die and a 7mm expander, as they do sell parts separately, and have an excellent expanding set-up for very short money. And if you want to do it in 2 steps, you could add a .270 expander as well.
Or you could just use a .284 FL die as well, and if you wanted to, you could have the neck area honed so it provided the proper amount of sizing as well, instead of overworking the brass as most FL dies do. Either way would provide a low cost and good performing expanding die.

The Lee decapping die is $12, and the expanders are $3 each. So for under $20 you can buy a die and 2 tapered expanders that should provide as good of results as you will get.

I think the Lee expander or the COW method will be two of the better methods for expanding. Although the COW may actually have a few benefits, as it will actually help improve concentricity if the case is out a bit, where as an expander can't really "fix" a case that is not concentric to start.

Here is a link to a picture of the Easy Expander:
http://www.leeprecision.com/graphics/parts/2315.jpg

FWIW, I have been using a Lee decapper die and expanders for any expanding that I do and really don't use my K&M all that much anymore, as the Lee works so well and costs so little that I can't see the point in spending more for K&M mandrels.

 

[falconpilot]

This is a good thread! Thanks for all the info..Now to the shop to experiment ;D

 

[Baron]

Ok Jim! I’d like to know how your time in the shop went! What did you come up with and did you solve the run out problem?
Baron