Fireform 6mm Dasher Questions...

D

DSM

Chuck
I plan on fire forming forming some 6 BR brass to 6 Dasher and have a couple questions. I am going to follow the method listed on 6mmbr.com in which the neck gets expanded to 25 cal and resized to 6mm part way down with a 6BR die to create a false shoulder.

Since I need a 6BR die for the sizing of the neck, what die should I get? A Redding full length bushing die or the neck die? My guess, since I will only be sizing the neck back down from 25 cal, a bushing neck die should work.

Now if I get a bushing die, what size bushing should I purchase to do the neck size? My chamber will be .264 neck.

TIA!
 
Standard 6mmBR FL Die

Do not get a bushing die. Use the standard FL die w/out bushings and w/out the expander ball and you'll be good to go! The 6mm bushings will crush the case mouth if it has been expanded to .25 cal.... The Radius on the bushing is not large enough to clear the OD of the neck.
Baron
 
Yes the Forster 6mmBR FL die should work like a charm.
Baron
 
I couldn't get the cases to expand without inducing runout so I hydraulically formed mine. Wasn't happy with the amount of stretch either, no matter what I did, the case got driven forwards by the primer strike until I hydraulically formed them. When I ordered my barrel from Ted Gaillard, he was kind enough to send me a rem 700 tent peg along with it. I chambered that old barrel on a Savage to fireform, which btw required full power loads to make nice sharp shoulders. FWIW, my reamer from PT&G and my 6mmDasher Redding FL sizing die are a perfect match, I was very impressed. I do my own work so the cost of the method I choose wasn't a factor.
 
Dasher forming

DSM-I've found one thing very helpful in expanding necks. I use the tapered expanders-if cal. available-when I can. Example; I used 6.5 taper to expand my 6BR (Dasher) for the false shoulder-then back to 6mm.They are so less "harsh" than a reg button. I did this also making my 6.5 Improved(before .260 came out) on .243 Win. I use them on all my dies on a regular basis. If you try this, I feel sure you'll replace all the standard buttons with tapers. Hope this makes sense. V/R Greg
 
I like the hydraulic die from Hornady

I have had good luck using the hydraulic die from Hornady. The case is formed enough to shoot test loads on the first firing. Here is a picture of the Hydraulic die along with a FL and seating die from Hornady. James Mock
 

Attachments

  • 2008_1210My0002.JPG
    2008_1210My0002.JPG
    36.5 KB · Views: 545
Greg, I have a K&M .25 cal expandiron...would that work ok?

I like the sounds of the hydraulic die since it will save some wear and tear on my barrel. Do you have to custom order them from Hornaday for the Dasher? Do they need fired cases to made a die? How accurate is the die in terms of case run out when its formed? Will head spacing be correct after forming?
 
Last edited:
Baron Graham said:
Do not get a bushing die. Use the standard FL die w/out bushings and w/out the expander ball and you'll be good to go! The 6mm bushings will crush the case mouth if it has been expanded to .25 cal.... The Radius on the bushing is not large enough to clear the OD of the neck.
Baron
Click to expand...
While this is probably true, likely you can still use a bushing die -- just take the bushing out for the first sizing. The hole in the die is usually close enough to final neck diameter to take the neck down to where a second sizing with a bushing will work.

While I don't shoot a dasher, I believe a .25 will be fine. Off topic, but I had a friend who had a "standard" (won't claim "SAAMI" without knowing for sure) 25/06 reamer. It cut a fine tight-necked 6.5/06 chamber . . .
 
6 dasher forming without expanding works pretty good as well.

one method i tried last week and this week was to load the bullet long to jam to force the case against the boltface,remove the ejector pin so there was no forward preload on the case,mine is a tight neck chamber so i had to turn the necks before firing, to know how far down to turn on the necks i turned untill the bolt would close and then went .010 more,the main headspacing being off of the bullet,loaded with a lower end br charge of varget , so far out of 40 cases 1 has split on the shoulder, i can live with that i think. i wore my safty glasses just in case some metal decided to come out but all is well.the gun shot well and the cases came out looking good but after the second firing i am sure the shoulders will be a little sharper,good luck sir. tim in tx
 
Two friends have done hundreds of BR cases to Dasher using the .25 cal. expander and then sizing to 6mm and then firing them in an old barrel.
 
Fire forming Dasher or BRX

FWIW:

I would suggest a tapered bushing expander instead of ball type expander.

If you are going to neck turn do so before and just below the new neck shoulder juncture.

Here are the methods I am familiar with:

1. Fire forming in chamber with 7/8ths load (hard primers) with bullet jammed
10-20 thou. I would make sure chamber is clean no residue. Wipe case
with light coat of motor oil.

2. Fire forming with Bullseye pistol powder with case filled with or without
cream of wheat.

3. Hydrolic forming with Hornady or simular type of die.

All methods have advantages and disadvanbtages of each other.



Rustystud
 
Expander ball

DSM-Sorry, I'm not familiar with expandiron. Tapered balls(Redding) are available at Midway. 'Bout $12. V/R Greg
 
I use false shoulder method.

Tried tight neck tension hard jam but still had 3 from 50 that pushed the projectile down the case and they didnt go off.

False shoulder method sucks when having to turn the necks before hand. Ok if you are fireforming in a spare barrel as then it would have no turn chamber.

My new Dasher getting built now I went for a 0.272" neck. Plan is to give them a very very light turn after fireforming, just to take the high spots, or I might not turn at all!

I use a 25cal Redding tapered expander, and then a standard 6mmBR neck die to take it back to 6mm. Bolt is firm to close on false shoulder. Have not had one split case nor one that did not go off using this method. Formed around 400 cases so far!

Cheers
AI
 
PEI Rob said:
I couldn't get the cases to expand without inducing runout so I hydraulically formed mine. Wasn't happy with the amount of stretch either, no matter what I did, the case got driven forwards by the primer strike until I hydraulically formed them. When I ordered my barrel from Ted Gaillard, he was kind enough to send me a rem 700 tent peg along with it. I chambered that old barrel on a Savage to fireform, which btw required full power loads to make nice sharp shoulders. FWIW, my reamer from PT&G and my 6mmDasher Redding FL sizing die are a perfect match, I was very impressed. I do my own work so the cost of the method I choose wasn't a factor.
Click to expand...

I did a serch on the hornady web site (I assume that they are made by hornady) for the hydrauic dies......No luck. Tell me more!!!

Thanks,
Tod
 
Contact a Mr. Lonnie Hummel at Hornady for your hydraulic forming die. You will need to send in 2 pieces of brass for him to grind the mandrel. JDMock posted a pic of the die in a box with 2 other dies, click the link a few posts above. It isn't rocket science, I made a mandrel like the Hornady in the pic without ever seeing one and simply used my full length sizer. The bad part is I scratched the die in the process. I used oil because it produced much more consistant results with nice shoulders. After removing the oil and thoroughly washing the cases with super hot water and a rediculous amount of soap, I found out all the oil does not come out. Many of the first ones I reloaded had killed primers. I loaded them up and fired them as soon as possible after that, storing the bullets pointed down as well.
 
PEI Rob said:
Contact a Mr. Lonnie Hummel at Hornady for your hydraulic forming die. You will need to send in 2 pieces of brass for him to grind the mandrel. JDMock posted a pic of the die in a box with 2 other dies, click the link a few posts above. It isn't rocket science, I made a mandrel like the Hornady in the pic without ever seeing one and simply used my full length sizer. The bad part is I scratched the die in the process. I used oil because it produced much more consistant results with nice shoulders. After removing the oil and thoroughly washing the cases with super hot water and a rediculous amount of soap, I found out all the oil does not come out. Many of the first ones I reloaded had killed primers. I loaded them up and fired them as soon as possible after that, storing the bullets pointed down as well.
Click to expand...
First, what kind of oil do you use. Second, after washing the cases I would have run the brass through the tumbler for a few hours.......Did you try that? I am thinking that the money spent on this die would pay for itself in bullets, primers, powder, barrel life, ect.... in no time flat!!!
 
I use isopropyl alcohol

Since no liquid will compress, I use rubbing alcohol rather than water or oil. After forming the cases, I turn them neck down in a loading block and let them dry. Good shooting....James
 
I used oil because I had a bucket of it out of my lathe when I changed it for break in. I didn't know there was still oil in the cases after I "cleaned" them so no I didn't try the tumbler. Since I have a spare rifle to fireform, I just loaded them up and ran down to the range. Took some water and a small towel to cool it down so I could should one after the other. I have no idea how much pressure it takes to make sharp shoulders but I can tell you 25gr of varget pushing 105's does the exact same thing as the hydraulic forming die. 30gr made nice shoulders and 34 is a hot load.
 
PEI Rob said:
I used oil because I had a bucket of it out of my lathe when I changed it for break in. I didn't know there was still oil in the cases after I "cleaned" them so no I didn't try the tumbler. Since I have a spare rifle to fireform, I just loaded them up and ran down to the range. Took some water and a small towel to cool it down so I could should one after the other. I have no idea how much pressure it takes to make sharp shoulders but I can tell you 25gr of varget pushing 105's does the exact same thing as the hydraulic forming die. 30gr made nice shoulders and 34 is a hot load.
Click to expand...


So you are saying that you get much better results from actualy FF your brass with full on loads than you do when forming cases with the hydraulic form die??.

How about accuracy wise.....is there any difference in accuracy between new, unformed brass with the 25 cal false sholder and cases formed with the Hornady die and fired for the first time.
 
You must log in or register to reply here.
Back
Top