Wildcat question

[Expat74]

A friend of mine and I were discussing calibers and came to the conclusion that having a gun in 7.5 FK would be cool. However, where we live (Switzerland) the caliber is verboten as in armor piercing (which is one level below the lethality of AK-74 poison bullets as we know). So no one is thinking about importing them as the ammo is equally unobtainium, dies are non-existent, so is load data.

There is one version of the FK Brno pistol with a 10mm Auto conversion barrel which made us think.. how about we take a 10mm and neck it down to .30 cal using a modified 7.62x25mm (Tokarev) die and load it to max OAL of 32.00mm (10mm Auto OAL).

We also have a barrel manufacturer nearby that we may be able to talk into making barrels for a Glock 20 / 40..

Looking for opinions from the collective.. thank you gentlemen.

[SOFMatchstaff]

You might consider the 9x25 Dillon round, barrels and reloading stuff for it are available over the counter.

[country gent]

Several things to consider when designing a wild cat round and the firearm for it
Brass and its availability, the parent case should be readily available and inexpensive
Forming, how many steps neck turning or reaming needed.
Loading, you will be on your own no published data to work from.

Aside from this a successful cartridge is very rewarding.

One thing that made the ackleys and some other so popular was they could be fire formed firing factory ammo in the firearm.

[Expat74]

You might consider the 9x25 Dillon round, barrels and reloading stuff for it are available over the counter.

I already have a 9x25 Dillon barrel for my Glock 20

[Texas by God]

So- in Switzerland it's mandatory to keep a current issue Sig full auto rifle with ammo in your home- but .30 caliber fmj pistol ammo and the new 7.5 FK pistol are not allowed?
Is that correct? Forgive my ignorance of Swiss law.

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[lar45]

I'm sitting in a tree stand right now, so don't have access to any cases to measure...
Isn't the 10mm and 7.62x39 very close in case head dimensions?
What about shortening 7.62x39 dies, run your 10mm brass in and have 7.62xshort ?
You could use a standard 7.62x39 chamber reamer and just run it in far enough to fit your 7.62short.
That would save on custom dies and reamers.
For load data, just use Quickload to find a starting place.

[lar45]

So I looked up some dimensions, the base of the 10mm is .425", the base of the 7.62x39 is. 447".
You could take a x39 case, measure back from the mouth to the 10mm length and see if the diameter is close.

[357Mag]

Expat -

Howdy !

If you can get / are allowed to us it, how about using 6.8SPC as the " parent " case ?

The base diam is only .003" smaller than the 7.5FK. The shoulder diam is .402", which can be " blown out " to .425"; if desired.

6.8SPC case length is .604" longer than is needed to form a 7.5FK-length case, but of course.... can be trimmed to length needed.
This option would result in a longer wildcat case, than can be obtained using a 10mm Auto case; with resulting increase in case capacity.

I DK whether you can get the 6.8SPC case, or.... whether it is verbotten in Switzerland ?


With regards,
357Mag

[Expat74]

So- in Switzerland it's mandatory to keep a current issue Sig full auto rifle with ammo in your home- but .30 caliber fmj pistol ammo and the new 7.5 FK pistol are not allowed?
Is that correct? Forgive my ignorance of Swiss law.

Sent from my SM-A716U using Tapatalk

As long as you are active duty in the army, it's either your P220/P75 or a SIG 550 that you're having at home when off duty (in a nutshell). You can buy them at the end of your service for a pretty low price. The 550 will be converted to semi auto though..

7.5 brno is considered armor piercing ammo by the federal police (who does their own ballistic tests), and since there is no ammo other than the presumably ammo piercing factory ammo..

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[Expat74]

We can get 6.8 spc but it's rare and pricy. Even pricier than 10mm magnum of which i thought as well.

Thanks for the hint with x39.. i'll definitely look into that.

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[sarky]

I'm sitting in a tree stand right now, so don't have access to any cases to measure...
Isn't the 10mm and 7.62x39 very close in case head dimensions?
What about shortening 7.62x39 dies, run your 10mm brass in and have 7.62xshort ?
You could use a standard 7.62x39 chamber reamer and just run it in far enough to fit your 7.62short.
That would save on custom dies and reamers.
For load data, just use Quickload to find a starting place.

No! the 10mm and 7.62x39 are not close. You can use a 10mm Magnum case and trim back after necking it down, Or trim a 6.8 SPC case back and neck. What you are suggesting is just another wildcat cartridge.

[sarky]

The issue I see with this cartridge is the .307 projectile diameter, instead of a .308 diameter. There are plenty of .30 carbine bullets that would work fine as is if the chamber was cut for .308 projectiles. I am in fact working on a magnum version 30mm/1.3 inch long case to be chambered in the a M1 Carbine. It should push a 110 gr projectile over 2,000 FPS.