necking down brass

8x68s

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I have purchased 6.5 Grendel Basic brass to size down to 6mmARC. The "basic" brass is close to the right length and has the proper rim diameter, etc. "Basic" also means the case is straight walled and needs to have a shoulder and neck formed. Problem: the straight walled case is nearly .40 in diameter. Question: what does one use to step down from a neck dia. of .40 to .274? Simple answer: not a 6mmARC die, LOL!!

So my real question is how do I get from .40 dia. to .274 in increments small enough to not squash my cases? Because the case is so short I can't use any other cartridges with neck sizes in between unless I bought every WSM sizing die from .30 thru .25 !!??

HELP! :oops:
 

P7M13

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  1. Bump the shoulder back the 25 mils first using a 6.5 die with the 30° shoulder.
    1. Use lots of lube - I use a coconut oil / alcohol mix
    2. Move the ram *extremely* slowly as you are pushing the shoulder back.
  2. Anneal.
  3. Then neck down to 6mm.
  4. Neck turn
  5. Trim to length
You may want to neck turn before necking down to 6mm.
 

GLTaylor

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Call Bullberry. Tell them what you want to do. They make simple neck sizing dies that go from cal to cal in brief, easy steps. What you want to do will take 2 dies. Both ends of the dies are used. They are simple threaded cylinders with a different cal on each end. Gently squeeze the necks down a little at the time with plenty of lube.
You will also need neck mandrels for each caliber to re-open the necks at each step. Anneal as suggested above. You'll probably have some turning to do too.
LSherm told me about this. He makes some extreme wildcats.
Good luck. You may need some!
 

can1010

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you need forming dies with proper body dia. so you have body support to keep case from folding over at neck shoulder or crushing at body shoulder. it is not as simple as necking down brass. the other option is buying a couple of Grendel dies and have the necks enlarged to form neck/ shoulder in multiple steps and keep steps small trying to take large bites at a time will only ruin cases. annealing will be necessary as brass work hardens and don't over lube your cases, you don't need any more than normal sizing

last thing take your time. setting up multiple dies for forming is not a quick and easy process
 

Mikecr

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If I understand correctly,he has no shoulder or neck form to work with.
In such a case I think he needs an actual forming die set (like Lee Six used to offer).
Lee6FormSet.jpg
 

Mikecr

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The maker (Lee) passed away in 2003.. As far as I can tell, nobody else offers a universal set.
I could loan OP mine, no charge, but with a hefty deposit.
 

8x68s

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Thanks gents!
I figured I'd have to make something for this situation. In the past I've been able to use other cartridges to get close. this one is too short for anything but can1010's method. I can use a modified 6 ARC die and a couple die blanks I have laying around. I'll have a die for each: 9mm, 8mm, 7mm and 6mm... Hmm,??
 

8x68s

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The maker (Lee) passed away in 2003.. As far as I can tell, nobody else offers a universal set.
I could loan OP mine, no charge, but with a hefty deposit.
I appreciate the offer but I would not want the responsibility for such a rare gem. Thank you!
 

L.Sherm

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As GL said call Bullberry, they will take care of you if you tell them what your doing and shoulder angle.
I've made about a 1,000 17 badger brass from 30 carbine brass and about 2,000 20VT and 20SCC from 223 brass.
I would not anneal or trim necks untill your necked down then anneal and run through full length die and then trim length and outside if necessary.
Theres likely hood of crushing the shoulders if your going down much ask me how I know.
 
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8x68s

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As GL said call Bullberry, they will take care of you if you tell them what your doing and shoulder angle.
I've made about a 1,000 17 badger brass from 30 carbine brass and about 2,000 20VT and 20SCC from them 223 brass.
I would not anneal or trim necks untill your necked down then anneal and run through full length die and then trim length and outside if necessary.
Theres likely hood of crushing the shoulders if your going down much ask me how I know.
yes, been there, done that with a couple of the first tries. I knew it wasn't going to work but crushed them anyway, LOL... I did anneal them initially though, based on Starline's advice. I'll get with Bullberry.
 

L.Sherm

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Theres no point in annealing before you start, it only makes the process harder since there work hardened is when they need annealed afterwards.
 
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