.20 cal. Wild cat question

[bobcat93]

Any one ever try to squash a .357 sig case neck down to .20 cal...if so what were the results.

 

[jepp2]

Any one ever try to squash a .357 sig case neck down to .20 cal...if so what were the results.

A 22 Jet isn't too far away from that. Just more case capacity.

 

[TAJ45]

Not what you asked, but a .30 carbine case may have more upside to scratch your small case 'cat itch.
If I just had to do something different, maybe use a 222 case for parent. Then mash it down as far as you like. No odd bolt face situations. (However, I have no idea of what a 357 Sig bf needs to be.)

 

[L.Sherm]

If you have the correct forming dies you can just about reform any case to whatever you want. Ive made about 1,000 17 cal cases from 30 carbine.

 

[457ciSBC]

No, but if I was going to do something on that boltface, I would start with the 10mm Magnum so I would have a slightly longer case to start with.

 

[NorCalMikie]

AND, if you look deep enough, somebody has probably already done it. (but go ahead and do it anyway)

 

[457ciSBC]

AND, if you look deep enough, somebody has probably already done it. (but go ahead and do it anyway)

I might have to ruin a perfectly good 10mm Mag case now....LOL. Don’t think I’m going to butcher any 357sig brass.

 

[chuckshooter]

360DW case to rimmed vartarg

 

[billshehane]

I had a S&W 6" 22 Jet and plugs and muff's were still not enough. Cool round on Ghogs and PD's. but LOUD for sure.

 

[JASmith]

Try using the ”Cartridge Search and Identification” tool on Ammoguide.com — you can enter a range for each dimension and it will find all of the cartridge designs that fit.

BTW They have more than 1,000 rounds in their database.

 

[Fast14riot]

I might have to ruin a perfectly good 10mm Mag case now....LOL. Don’t think I’m going to butcher any 357sig brass.

Star line sells 6.8spc basic brass, which would get you the same as 10mm/40s&w. Some guys are playing with a 40 cal in the basic brass, makes for a decent little thumper!

 

[B23]

It's unfortunate the FN 5.7x28 brass isn't better stuff because necking one of those down to .20 or .17 could be a fun little cartridge.

 

[AWS]

A popular round in the old Martini actions was the 222 Rem rimmed made from 357 Maximum. You can get already made 222 Rem Rimmed cases from Bertram Brass and most of the heavy work is done already.

 

[flatlander]

The PDK line of varmint cartridges for AR15s uses 6.8 SPC as the parent brass; I've formed 22PDK from Hornady 6.8SPC, and got some really nice cases out of it. The last batches of PDK brass I purchased were headstamped '20 PDK', and had to have necks expanded to .22 cal for use in my 24" bbl'd 22 PDK AR15.

I'd have liked to have been able to buy a Howa Mini action with the correct boltface for use with 6.8 SPC and the whole line of wildcat designs using that case as the parent, but it was far simpler to just buy a 20 Tactical reamer and use a Howa Mini in 223 Rem as the donor action...and if it was possible to get a Mini bolt with the SPC boltface, I'd have gone with rounds formed on the 6 HAGAR case instead of using the shorter 6.8 SPC.

 

[JohnHenry]

Any one ever try to squash a .357 sig case neck down to .20 cal...if so what were the results.

Some additional 20 caliber food for thought.

Cartridge Comparisons

Check out http://tripledeuce.net!

tripledeuce.net

 

[bonecca]

You can take a 256 winchester mag and start there. That will get you half way there.
Chuck

 

[TAJ45]

Not to be sparky, but what ready, reasonable sources of brass are there?

 

[B23]

Any one ever try to squash a .357 sig case neck down to .20 cal...if so what were the results.

Wouldn't this be about the same or real similar as the 22 TCM?

I'd think sizing down something with that short of neck would probably be kind of a PITA because you'd risk pushing the should back or collapsing it in the necking down process. Also, with a case that short I wonder if extraction would be an issue.

 

[TAJ45]

I just recently took old, Win '06 unfired and pushed the necks back abt 3/4 inch, with an eventual o.d. of .248 for a bud. Started to frequently mash the shoulders. No annealing done during the process.
I coul not find my PBike reducing dies but cobbled some bits and bobs of 6BR forming, bushings and a few Skip Otto pcs. to get the job done. The gaps were large enough that I had to chamfer the nk OD to get them started......not the slick op I planned. When you can't find what is needed, PUNT.

 

[small caliber lover]

Not what you asked, but a .30 carbine case may have more upside to scratch your small case 'cat itch.
If I just had to do something different, maybe use a 222 case for parent. Then mash it down as far as you like. No odd bolt face situations. (However, I have no idea of what a 357 Sig bf needs to be.)

Pretty sure Calhoon has done this with one of his 19's