Whidden Custom Dies

I cant find a way to neck size my 7 Mega
What's the dimension of the base of the shoulder? I use a 25 WSSM neck die from Redding as a universal bushing neck die because it had the largest diameter I could find at that point, an so far every case I've put into it has been fine.

You can also order a blank neck sizing die from LE Wilson and use the chamber reamer to cut the die - if it chambers it'll neck size only. I normally get an in-line seating die cut when the first barrel is chambered with a new reamer, so a sizer is not much extra work to get done on top of the barrel and seater.
 
Easier said than done sometimes depending on the cartridge. I cant find a way to neck size my 7 Mega , so I just bought the Hornady dies.
the Hornady 7 mag neck die will size the 7 Maga without a problem. its .568 at the base and basically straight walled. i have a bunch of those neck dies just for this purpose
 
the Hornady 7 mag neck die will size the 7 Maga without a problem. its .568 at the base and basically straight walled. i have a bunch of those neck dies just for this purpose
Only a Hornady die? I have a Lee and RCBS and it wont neck size. I ran into this a few times doing wildcats, but once you get the dies set up, it's pretty neat.
 
What's the dimension of the base of the shoulder? I use a 25 WSSM neck die from Redding as a universal bushing neck die because it had the largest diameter I could find at that point, an so far every case I've put into it has been fine.
.533 on the 7 Mega
.484 on my 7 RM
 
Only a Hornady die? I have a Lee and RCBS and it wont neck size. I ran into this a few times doing wildcats, but once you get the dies set up, it's pretty neat.
only Hornady has generic neck sizing dies to my knowledge, they are great for wildcatting. just watch there is standard that does to 284 win dia. cases and mag that will do WSM/RUM size cases. the 338 mag will do Lapua size cases. I will take a press and supplies right to the range so i can get fully formed cases before i send them out.
 
.533 on the 7 Mega
.484 on my 7 RM
223/243/25 WSSM are all .5457 so any of the bushing neck-sizing only dies from Redding would work for your 7 Mega if you needed to neck size.


only Hornady has generic neck sizing dies to my knowledge, they are great for wildcatting.
The Hornady neck dies I have are fixed neck OD, I prefer using the WSSM die because I can put whatever bushing in that I want to.
 
223/243/25 WSSM are all .5457 so any of the bushing neck-sizing only dies from Redding would work for your 7 Mega if you needed to neck size.



The Hornady neck dies I have are fixed neck OD, I prefer using the WSSM die because I can put whatever bushing in that I want to.
that only works if you have matching shoulder angles. the 223 wssm is 28 and the 25 wssm is 30 the maga is 40 if i remember correctly. you will destroy the shoulder if you try
 
...you don't put the case all the way into the die. It's a NECK die. You size about half the neck.

I mean, I've only done this several hundred times, what do I know 🤣 I use the 25 WSSM die, maybe the shoulder angles are why. It's been a few years since I bothered to look at why it works, because it works. I have the Redding comp neck sizing die, screw the mic all the way down and the case neck is sized just fine.
 
we're talking forming brass for die makers not for everyday sizing. besides you would never to just neck size a high pressure hunting cartridge that is a waste, you full length size with slight shoulder bump. besides why spend $100 for die and bushings when $25 will do and then can be used across multiple cartridges.
 
I just went and took the die off the shelf, the only thing I think I did to it was drill out the neck in the sliding sleeve to 3/8 (I think? A 3/8 bit passes) to let 338 LM brass into the bushing. Maybe I never had problems because that cut "fixed" the shoulder angle issue by shortening the shoulder relative to the bottom of the bushing. Everything else looks original in the die. I added a bearing sleeve to the bushing stem so the inner sleeve doesn't have to compress for the case neck to enter the bushing. No case should touch the inside of the sliding sleeve at any point, that's the point behind it being a neck die.

I use this die mainly to set false shoulders for fire forming improved cases, so it never tried to bottom a bushing into the neck/shoulder junction even though it probably could. Would work perfectly to minimally half-size a neck to blow out a case for measurements for a custom die.

we're talking forming brass for die makers not for everyday sizing. besides you would never to just neck size a high pressure hunting cartridge that is a waste, you full length size with slight shoulder bump. besides why spend $100 for die and bushings when $25 will do and then can be used across multiple cartridges.
I'm aware of what we're talking about. đź‘Ť Have a good day.
 
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Nope I lied, found a sleeve spacer on the bushing stem, that stops the sleeve from compressing so the case shoulder never touches the sleeve.

Redding makes a 358/25 WSSM die in their custom lineup that wouldn't have to be modified for 30 cal+ cases.
 
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