Show us your wildcats!

[Chev. William]

My Current Mildcat/Wildcat is the "6.35x32mmSR STEWART" which is listed in "Ammoguide International" 'Cartridge Master Database as their Cartridge number 950. It Was Published on September 1st this Year. Parent is a 5.7x28 that is Neck/shoulder Expanded to fit a .250" Bullet then reduced in body diameter to .276" nominal as a 'straight walled' case.
13.8 grains H2O Estimated Volume. So far I am working starting LIGHT loads to use in a Rebuilt Stevens 1915 Favorite Action. With charges starting at 1.0 grains of Bullseye, and increasing by 0.1 grain steps. Bullets are of two types: a 74 grain Lead RFN GC .257 Sized down to .252" or .251" and a 50 Grain FMJ-RN Jacketed one.

Best Regards,
Chev. William

ADDED 20161220: Copy of Ammoguide #950 Drawing for 6.35x32mmSR Cartridge Case


I have an 8-shot cylinder that is Reamed with PT&G ".250ALRM" Chamber reamers to use in my Ruger Converted Single Eight Revolver to fire this cartridge design with a OAL of 1.395" to 1.400" (shorter than the Rifle loading OAL).
Chev. William

[FergusonTO35]

I think that cheap and plentiful .223/5.56 brass necked up to 257 or .264 would be pretty cool. Wonder if doing so you could approximate .25-35 performance? There are bunches of cheap bolt actions and AR's waiting for a project like this.

[Hamish]

I think that cheap and plentiful .223/5.56 brass necked up to 257 or .264 would be pretty cool. Wonder if doing so you could approximate .25-35 performance? There are bunches of cheap bolt actions and AR's waiting for a project like this.

https://en.m.wikipedia.org/wiki/Thompson/Center_Ugalde

Maybe someday I'll get around to that 7TCU AR.

Meanwhile, back at the Batcave,,,,,,,,,

Attachment 148556

[Whiterabbit]

Maybe someday I'll get around to that 7TCU AR.

[Southern Son]

https://en.m.wikipedia.org/wiki/Thompson/Center_Ugalde

Maybe someday I'll get around to that 7TCU AR.

Meanwhile, back at the Batcave,,,,,,,,,

Attachment 148556

Must be the bat cave............everything is hanging from the roof!!!!!!!!!!!!

[Chev. William]

Second Published "Mildcat"!
The "6.35x28.6mmSR Stewart" was published 11-25-2015.
It is a Modern replacement for the .25 Stevens (Long) and is Easier to form than the .25-10 Halsted.
Case volume is Estimated at 12.3 grains of H2O by Ammoguide, which is slightly more than the Halsted's 12.2 grains.
This is a 6.35x32mmST trimmed to !.125" nominal Length. it will fit an original .25 Stevens (Long) RF chamber. It would use Conversion to CF of the Action. Alternatively, it could be Drilled and reamed to hold a .22RF Blank and be used in a RF Action.
Pressure Limit is specified as 50,000psi Piezio CIP, the same as the Parent 5.7x28mm Cartridge. Down Loading to about 25,000psi would match RF MAP limits and be suitable for Ruger .22 Cal single Six conversions. This loading would also be useful in a Stevens Model 44 action and, if further downloaded, be usable in an original Stevens Favorite Action (at about 1000fps to 1100fps).
PT&G have Made me both a Roughing Chamber reamer and a Finish Chamber reamer for this Cartridge Design and I am waiting For my gunsmith ot work down his Backlog before passing them to him to re-cut Chambers in a donor 8-shot Cylinder.

See my thread on converting a Ruger 'Single Six' Revolver to this cartridge on this Web site.

Best Regards,
Chev. William

Added 20161220: copy of Ammoguide #958 Drawing of 6.35x28.6mmSR Cartridge case:

Chev. William

[Ratau]

My 22LR "centre fire" cases to be used in a Thompson Contender. At the back one loaded with a 30 grain solid brass bullet.

[Whiterabbit]

OK, that is awesome.

[No_1]

My 22LR "centre fire" cases to be used in a Thompson Contender. At the back one loaded with a 30 grain solid brass bullet.

Could you give us a little info about this one? It sure is nifty!

[cainttype]

Thought I'd add these to the archive.
Rebarreling a standard 308 (or similar bolt action) to an oddball thumper without action modifications?... The question comes up occasionally, so here's a couple options.
If you're restricted by the "straight-wall, non-bottle-neck, 1.8" max case lenth" rules, the .413" version should be very attractive.

The original case was a 270 Winchester. It has been formed into a belted 240 Weatherby (same rim and head diameter of 308/30-06), allowing the cartridge headspacing to be controlled by the belt instead of relying on a bottle-neck's shoulder.
The 270-to-240 operation is completed with a single pass through a forming die available from CH4D (on a stout press... I use a RCBS A2), then simply trimmed to length.
The cases of the 270 or 30-06 cut at the "lower" shoulder junction can easily provide a 240-type basic belted straight-wall of 1.9". The 280 Remington case can easily provide a 2" version.

These examples are in .375" with a minor shoulder (could just as easily been a straight taper) and a .413" belted "straight-wall". Both cases are trimmed to 1.8".

[Chev. William]

The Latest of my Mildcat designs is now Registered with "Ammoguide Interactive" as the "6.35x26mmSR Stewart/.25 Magnum Auto" (#971). it is another Trimmed Version of the 6.35x32mmSR cartridge with a potential range of length from 1.024"to 1.056" (~.032" Range) to allow experiments and developments. the Water capacity is listed as 11.2 grains.
PT7G has made and delivered a Finish Chamber Reamer for This Cartridge for a Maximum case length of 1.060" to allow for Possible brass growth in use.

Here is a copy of part of the "Ammoguide Interactive" page #971 for this cartridge containing the Drawing of the Cartridge Case:


Best Regards,
Chev. William

[Polar_Hunter]

7.62 x 39R,,,,This one shoots great and is set aside till my grandson gets old enough to begin shooting center fire.

https://www.youtube.com/watch?v=gBKznImAYtk

[Whiterabbit]

Here;s 223 necked up to 357 cal. First is a 9mm bullet, second is a 200 grain jacketed. Should be able to handle up to 300+ grains with ease. No modification needed to feed lips that I can see, just magazine body to remove the ribs that support 223 necks.

Basically a 300 BO on steroids.

[mcdaniel.mac]

Here;s 223 necked up to 357 cal. First is a 9mm bullet, second is a 200 grain jacketed. Should be able to handle up to 300+ grains with ease. No modification needed to feed lips that I can see, just magazine body to remove the ribs that support 223 necks.

Basically a 300 BO on steroids.

This makes me moist. What kind of velocity are you getting?

[Whiterabbit]

first, haven't built the gun. Yet.

Second, I plan to build it off a 9mm AR barrel, which means blowback operation, and I will weight tune it to operate with 300 grain cast lead projectiles at 1000 fps.

If I intended a supersonic cartridge, I'd figure out how to make it a gas operated design, I don't think you can source cheap .357 cal barrels with standard extensions.

---------

It could probably do ALOT better than 1000 fps, but I'll never know it. I want something with no recoil in a small package that fires a huge bullet that will deliver energy in a quiet quiet package.

[mcdaniel.mac]

first, haven't built the gun. Yet.

Second, I plan to build it off a 9mm AR barrel, which means blowback operation, and I will weight tune it to operate with 300 grain cast lead projectiles at 1000 fps.

If I intended a supersonic cartridge, I'd figure out how to make it a gas operated design, I don't think you can source cheap .357 cal barrels with standard extensions.

---------

It could probably do ALOT better than 1000 fps, but I'll never know it. I want something with no recoil in a small package that fires a huge bullet that will deliver energy in a quiet quiet package.

200gr+ at 1000 sounds plenty neat to me. I have wondered about something similar myself, perhaps based on the Remington 7615P.

I will eagerly look forward to more news on your work.

[TRX]

There's a guy by the handle of "moleman" on Weapons Guild and Gunco who built one of those a few years ago. He has some loading data for that cartridge when you get to that point.

[Moleman-]

Hi TRX! Guess I never added these to this thread. Right to left: 357AR (357Max-rimless at 223 pressures); 44BGML/44x1.6" (sort of like a 445SM only rimless with more case taper); 44BGM 44x1.8" velocity similar to a 444 marlin . Then a couple of guns they're chambered in. Tan ar15 is my sons 357AR. Got a couple more including a pistol that I used for deer hunting until they allowed pistol caliber rifles a few years ago in lower MI. 1891 Mauser is in 44x1.8" with an octagon barrel, made the front sight and sling swivel base from scrap. I do limit the pressure in it. SS barreled ar15 is in 44x1.6" with a piston setup and the ar10 is in 44x1.8"

[Moleman-]

Whiterabbit, The Pmags are a great choice as it is easy to remove the bullet guides in the front of the mag with a dremmel and a sanding drum to allow the rounds to double stack. Depending on bullet length and profile if you're getting bullets hanging up you can trim the feed lips back a little so they release the cartridge bases sooner so they're not being held down while the front of the cartridge is trying to straighten it's self out to chamber. Only an issue for me on heavy cast or seating 180gr xtp bullets out far. Pointy or even round nosed like the speer 200gr seem to feed fine long. There is a much better bullet selection in .357" & .358" so I went that route with a locked DI action and 1:14" .358" blanks (did make a couple on .357" blanks). I did post up how I'm forming cases recently in the case forming section http://castboolits.gunloads.com/show...223-5-56-cases The less chamber taper you have the longer the cases last using a standard 357Max die set. Much more over .382" for a reamer base diameter and you'll have to trim the cases every other shot. The extra dia from the loose chamber is turned into extra length upon sizing. With a straight chamber I was able to get up to 12 firings before trimming but it was very finicky chambering. It may not be an issue with lower pressure rounds since the web is much thicker on 223/5.56 cases but I thought I'd mention it since the 9mm luger has a chamber mouth in the low .390's. Good luck on your project it sounds interesting!

[Moleman-]

Mag pic