6mm ARC sizing Woes

[danr]

I’m sure others must have had this happen. 6.5 Grendel Starline brass sized down to 6mm ARC using a Hornady Custom Grade full length sizing die with Imperial sizing die wax and a LE Wilson case gauge. Even though using Imperial wax sparingly, effort needed to size fire formed brass is excessive to the point die will push brass and form a belt at bottom of case body. Do I have a bad die?

 

[alamo5000]

Are you trying to use it with the expander still in the die?

I use a Mighty Armory die to form my 6 ARC (from Starline 6.5 Grendel brass) and it doesn't look anything at all like that.

I would venture to say that something is wrong.

 

[DeadFox]

I think it’s the die base diameter. I’ve seen photos of that before. My lee FL die doesn’t do it. Only resized twice so far, so hoping it doesn’t show up down the road but so far so good

 

[357Max]

Read Hornady die & didn’t even need to look at picture. It seems their 6ARC die is basically an unadvertised small base die.

LE wilson die is also GTG for 6Arc if you want a bushing die. That’s what I’m using.
I agree with Alamo if you want a non bushing die go with Mighty Armory. Have them in 4 other calibers & they’re great die’s.

 

[danr]

Yep weird I didn’t have this issue when I first sized the the new brass (effort to size was excessive I thought). This is after brass was fire formed in chamber.

 

[918v]

That’s because the new brass hadn’t expanded to fit your chamber. How much is the die sizing? What is the base diameter before and after?

 

[357Max]

I had found the Hornady brass or some of it is .003 undersized at the .200 line. Probably matches their FL die.
The Lapua & Starline Grendel I measured was right on saami spec at the .200 line. The LE Wilson FL die is also saami.

I've repeatedly seen reports of the Hornady FL die leaving this step on Lapua & Starline brass.

After 3 firings on the Hornady brass with fairly hot Lever loads it still hasn't blown the Hornady brass out to saami at the bottom. Still has a reverse step where the Wilson die doesn't touch.

Below link shows where I measured it.
https://www.snipershide.com/shootin...e-belted-magnum-problem.7112215/post-10119157

 

[supercorndogs]

Back when you couldn't find any dies anywhere, I had a 264 LBC RCBS small base die that did that to brass. I polished the die with 600 grit until it didn't do it anymore.

 

[67rschev]

Using the RCBS FL bushing die here, and it is also GTG both bolt and a semi.

 

[danr]

I think it’s the die base diameter. I’ve seen photos of that before. My lee FL die doesn’t do it. Only resized twice so far, so hoping it doesn’t show up down the road but so far so good

Yep I got a hold of a Lee FL sizing die and sizing the Starline brass now is near effortless.

 

[mrrogers1]

Yep I got a hold of a Lee FL sizing die and sizing the Starline brass now is near effortless.

Would you be able to measure and post the ID of the base of your Hornady and Lee FL sizing dies? I might order a Redding FL sizing die (I use for many other calibers), get Lee or machine the Hornady die to alleviate the issue. Seems so odd that Hornady would mis this on their own cartridge.

 

[danr]

Would you be able to measure and post the ID of the base of your Hornady and Lee FL sizing dies? I might order a Redding FL sizing die (I use for many other calibers), get Lee or machine the Hornady die to alleviate the issue. Seems so odd that Hornady would mis this on their own cartridge.

Couldn’t get the decapping pin out of the way on the Lee die to get a good measurement with the tools I had. The Hornady die measures 0.436

 

[mrrogers1]

Couldn’t get the decapping pin out of the way on the Lee die to get a good measurement with the tools I had. The Hornady die measures 0.436

Thanks for the effort! The way the decapping pin is held in on the Lee does leave a little to be desired (I have a couple sets from when I started reloading) so I do understand. As I went a bit further into the rabbit hole, I am (hopefully correctly but I don't think I am) of the mind that this is a hornady brass thing, not a die thing. I don't use Hornady brass (500pc converted Starline 6.5 Grendel) so I'll just keep an eye on this.

Thanks again!

 

[FuhQ]

I’m sure others must have had this happen. 6.5 Grendel Starline brass sized down to 6mm ARC using a Hornady Custom Grade full length sizing die with Imperial sizing die wax and a LE Wilson case gauge. Even though using Imperial wax sparingly, effort needed to size fire formed brass is excessive to the point die will push brass and form a belt at bottom of case body. Do I have a bad die? View attachment 8080121

You have a die cut to improper size. Contact Hornady. This happened to me with my RCBS .264 LBC dies when the 6.5 Grendel first came about. RCBS cut a bunch of them too small, and it caused a “belt” (donut) at the base…Just like pictured. I didn’t reload for it for years after that. Then when RCBS started making actual 6.5 Grendel dies, I bought a set, and haven’t had any issues since.

 

[danr]

Okay, this is still a problem even after trying a 3rd die. Hornady, Lee now a Forester FL die. So I’ve read now that if you’re running your loads at max end, sizing will crush cases because the case walls at the base of the Grendel/ARC are thin. Are you’all dealing with this. I have some new Starline ARC brass and will reduce powder charge and start over and see if that eliminates the sizing issues I’m still seeing. A bit disappointing considering the hype was better velocity over the Grendel.