6mm-284 and Hornady Die Problem/Question

[Chappy6mm]

I am having a problem with my 6-284 brass in the Hornady Custom Grade FL Dies I purchased.
After running the brass into the die and sizing, the neck does not want to come back over the expander without a lot of force. I even had one that would just not come back out (over the expander) and had to take the die apart and spray some case lube down the neck while the spindle and expander was still in the case and then it was still tough to get it thru. The brass is Lapua 6.5-284 and I brush the inside of the necks. I have been putting a touch of Lee resizing lubricant on the inside of the neck and it helps but something just doesn't seem right. Any idea what it could be? I am thinking I need to neck turn after sizing the 6.5 down to 6 but the gun is shooting so well I don't want to mess with anything.

 

[WyleWD]

I had the same issue with a 6-284 and Lapua brass that was 6.5-284. So after a few of those as you describe, I turned the necks and took about a thousandth off and no further issues. I don't know if it will help you but that is how I got out of that fiasco. WD

 

[Chappy6mm]

That's what I was thinking WD. Had to be a neck thickness issue. I didn't want to have to turn necks on this one but I guess it will be better than fighting the press and stretching brass and pulling on shoulders.

 

[cba257]

Necking down brass always makes it thicker; and I think Laupa brass is thicker to start with. I would also think turning the necks a bit will help. It won't hurt accuracy either.

 

[dennisinaz]

You should neck it down before sizing it down so you don't get a donut. Make sure the expander ball isn't too big and make sure you lube the inside of the neck liberally. The wax works fine for me.

 

[Patch700]

Have you considered removing the expander setup during the necking down process , then run them up into the expander afterwards ... So long as the expander isn't too large or need polishing it may help with stretch issues.

 

[CJ6]

I use bushing dies and take the expander out. I de-prime with a universal de-primer (RCBS) then clean the cases then size. Neck thickness can be an issue as is the chambers NK diameter and the dies neck diameter. There is NO standard neck diameter for the 6-284 (although common sizes are .276, .272, .268). Take the expander out and size a case, measure the neck diameter and neck thickness and see where you are at. My 6-284's are .276 (chamber neck) loaded round (Lapua 6.5x284 brass) is .274 (UNTURNED) and use Reading bushing dies with a .273 bushing and NO expander. This give me .0155 neck thickness (admittedly on the thick side) but I anneal regularly and had no troubles with this system.

 

[jonbearman]

Cj6,my thoughts exactly especially the annealing. When I made brass for my buddys 6-284 we had no problem with the expander but we used norma and hornady with great results.

 

[Chappy6mm]

Here are some numbers for you guys to see whats going on.

Piece #1 - Sized without Expander/Decapper Neck= 0.263
Piece #2 -Sized with Expander/Decapper Neck=0..272

Looks like expander has to pull out .009. Is that too much? Seems like this would really work harden brass.

Neck thickness is 0.018

An unsized fired round measures 0.2745 With springback do you think my chamber is .275?
A sized round with a bullet seated measures .274

 

[Chappy6mm]

After putting the expander in a drill and polishing with steel wool and swabbing the inside of the neck with a q-tip and Lee resize lube the process has become much easier. I think I will start annealing these to cut down on work hardening but no neck turn for now.

 

[CJ6]

Judging by the "fired unsized NK Dia". I'd bet you have a .276 chamber NK Dia. The sizing die is squeezing the NK down WAY to tight. Look into either buying a FL bushing die with .272/.273 Tin bushings or have your dies Neck opened up by someone COMPETENT to do this., But IMHO you'd be better off with the FL bushing style dies. You are going to have to anneal these cases at some point preferably right after you first neck them down and before the first firing or you'll be splitting necks (I do mine every other firing and have 40+ firings on this batch).