Dasher fireform question and method discussion.

[skeetlee]

I am having to load 32gr of varget with 107 sierra bullets stuffed 20thou into the lands to get my cases to form all the way out. Does this sound like a bit to much powder? There doesnt seem to be any pressure issues. I also thought that i should feel some restriction when i chamber an unformed 6BR case into the dasher chamber, and i dont feel much resistance, just the bullet stuffing into the lands. I am not really to worried about it just thought i would mention it. I just wondered if 32gr of Varget sounded like a bit to much powder with a 107 sierra?? Its working pretty nice though. Cases look good!! I am doing my brake in with one shot and clean and its a pain in the neck as i am getting a bit more copper than i would like to see in this new krieger gain twist barrel. Thanks Fellas!


I would also like to discuss what method is thought to be the best method to use while fire-forming. I am using the bullet jam method but i have been told the false shoulder method is a better idea. I assume it has to do with straighter cases. I ordered the tooling to do the false shoulder method today. Does anyone have anything they would like to add to this? I would love to read what you have to say!! Thanks Lee

 

[nmiller]

Skeet, that is the powder charge I used to fireform my Dasher brass and it worked great for me. I used the false shoulder method coupled with a .010' jam and a 105 A-max though. There's a shooter I know who used the jam method and had fit, pressure, and accuracy troubles. He formed new brass using the false shoulder and his Dasher rocks now. Just a thought... good luck with it.

 

[Bkluke]

I'm useing 29 gr of Varget w/107 smk's. I go with a hard jam of .080, seems to blow them out ok. Don't lose that many either.

 

[skeetlee]

I changed the topic a bit on the first post. I would like to hear your thoughts on the different ways of fire-forming a dasher. thanks Lee

 

[Bkluke]

I think I'm gonna buy Hornadys hydraulic forming die. Which forms the case with water.

You use a spent primer and then fill case with water run it up in the die and use a dead blow hammer to ram down a rod and bingo a fierformed case.

Would save alot of components. :thumb:

 

[memilanuk]

I kind of stacked the deck on mine... I necked up to .25 cal using a tapered expander, necked back down to .24 cal just enough to barely chamber, then I seated the bullet long,+0.010') into the lands with fair neck tension,0.003' or so) and lubed the case body to boot. *Most* of mine I fired with a little bit lighter load... 31.6 or so of I4895. Made a mistake along the way with the powder measure that cost me a few cases. Everything else formed pretty smartly on the first go.

If I were starting with new virgin cases I think I'd look into those hydraulic dies as well.

 

[holstil]

I blew out 2 hundred with 31gns. of varget and 65gn. pills with the false shoulder,bullet no where near the lands). I expanded up to .284 then resized down till it felt right in the chamber. I'm using a no turn chamber. Every piece of brass formed well, and I didn't loose one. Lapua brass.
Have fun, Jim

 

[shoerjbh]

Skeet

In response to question about fireforming cases for 6mm Dasher.
Recently I had one of my rifles Rebarreled to a Dasher.
I fireformed 55 cases with absolutely no problem.

I did not create a false shoulder

My rifle has a .269 neck, I turn the necks down to .2665
Made all length equal, reamed the inside of the case mouth just as if they were finished cases.

The method I chose was to put 31 grains of Varget behind a 108 Berger,
Then done what I think is a very important step, I sized the necks down two.261 so I would had very tight neck tension to hold the bullets in-place.
Then set my bullet 25th into the rifling.

I was surprised that it actually shot pretty good groups while fire forming,I know that's not important but it made me feel good that the barrel showed potential.)

I hope this helps
shoerjbh