My new 35 cal wildcat

[Wilkup]

While putting together my 35/300 WSM this year, I decided to rebarrel my Howa Mini to .35 caliber as well.
The rifle started as a 6mm ARC, but it never felt like enough for the hunting I wanted to do. It’s a super light, handy rifle, so instead of selling it, I committed to keeping it and building something better suited to my needs.
This led to my first wildcat project.
After talking with someone who did a Dasher conversion on a Mini, I started looking at options. My rifle has aftermarket bottom metal with a hinged floorplate, giving me a 2.45" COAL, just under a 0.25" gain over standard AR-length mags. I’d already been loading the ARC long, which got me thinking about running a shortened .308-based case.
I necked a .308 case up to .35 and started test fitting. A 200gr TTSX was too long (even after clipping the tip) so I trimmed the case to land at 2.38" COAL, which feeds from the magazine.
From there, it clicked.
I prefer monos, and Hammer offers a 140gr bullet that fits this concept perfectly.
I worked with Dave Kiff at PTG to design a reamer, with the goal of using standard .358 Win dies. After a few iterations, we landed on a final design I’m really happy with.

Specs:
- Starline .308 Match brass (SRP), necked to .358
- Trimmed to 1.90"
- 140gr Hammer bullet
- 2.40" COAL
- Bore rider/stepped throat

The goal is to push close to .358 Win performance out of my 18.5'' compact, lightweight, Mini action.
We’ll see how it performs this season, but I’m very excited about how it is all coming together.
Still waiting on my reamer to arrive but have:
- Starline 308 Match brass
- CCI/Federal SRP magnum/BR primers
- X-caliber barrel
- NECG banded front sight
- Talley QD rings and removeable peep sight
Will post photos of progress and completed project when finished and bring y'all along for the load development portion this summer. As stated, I'm very excited about this compact little powerhouse I'm putting together and can't wait to hit the hills with it this August.
Photos of my Mini in current form and the dummy round I sent in to PTG for pulling final dimensions for reamer design.

 

[roklok]

Very cool project !! I love 35 caliber, and I really like the Howa Minis, though I dont own one (yet). Keep us posted how it performs.

 

[Wilkup]

Very cool project !! I love 35 caliber, and I really like the Howa Minis, though I dont own one (yet). Keep us posted how it performs.

Thanks! I’ll definitely be keeping this thread updated as the build continues.
One thing I wish were an option on this little rifle was the option for CRFing. Something like the M704 Legendary Arms used to make or Sako 85 on this little Mini would take this rifle from damn near perfect to an over the top mountain/truck/everything inside 300 yards gun of perfection.
When I stop dreaming, I think I’ll be dead lol
Once I get the reamer, this gun is headed to the smith and then off for a complete DLC coating on every metal on the rifle, I’m even pulling the sling studs to send in.
All that to say… you really need to get yourself a Mini brother, especially if you want something like I’m building. I’ll even let you borrow my reamer ;P

 

[Grumpy gumpy]

Following with interest
Gumpy

 

[wildwilderness]

Well I would say a 35 WSM is a wildcat, but creating your own cartridge and making brass is a whole ‘nother level!

 

[Wilkup]

Well I would say a 35 WSM is a wildcat, but creating your own cartridge and making brass is a whole ‘nother level!

Touché!
Since I reload no matter what anyway, can buy dies OTC, and didn’t have to design/purchase a custom reamer I forgot it still counts.
Designing my own/first wildcat around a little rifle I’ve been obsessed with since they came to market has been so much fun and I might be a little depressed when I finally get it all wrapped up… if that’s the case, I may be on the hunt for a machinist to create a one-off specialized CRF bolt similar to the M704/Sako 85

 

[AZDAVE]

Did you open the bolt face up or get a different bolt? I like your concept.

I have 3 mini's 6ARC, 6.5 Grendel, 7.62x39. They a re fun little rifle that shoot way better than I expected them to.

 

[Wilkup]

Did you open the bolt face up or get a different bolt? I like your concept.

I have 3 mini's 6ARC, 6.5 Grendel, 7.62x39. They a re fun little rifle that shoot way better than I expected them to.

The bolt face will be opened up at the same time as the feed rails get modified.
These little Minis group WAY better than they have any business for the cost. My ARC in current form shoots five rounds of the 90gr Hammer HHTs into one hole with a healthy dose of Leverevolution. Unfortunately, it wouldn’t group as well with the factory Hornady ELDM offering.

 

[Wilkup]

Action was shipped off to LRI this week and I was quoted ~2 weeks for the turn around.
My PTG reamer arrives 1 week from Monday and my smith is ready and waiting!
2-4 weeks for the barrel and front sight installation and then off to DNA for the DLC treatment of all metal parts. Another 3-4 weeks there and I’ll have it back in hand with plenty of time to spare before bear season kicks off August 1

 

[Bob Nelson 35Whelen]

While putting together my 35/300 WSM this year, I decided to rebarrel my Howa Mini to .35 caliber as well.
The rifle started as a 6mm ARC, but it never felt like enough for the hunting I wanted to do. It’s a super light, handy rifle, so instead of selling it, I committed to keeping it and building something better suited to my needs.
This led to my first wildcat project.
After talking with someone who did a Dasher conversion on a Mini, I started looking at options. My rifle has aftermarket bottom metal with a hinged floorplate, giving me a 2.45" COAL, just under a 0.25" gain over standard AR-length mags. I’d already been loading the ARC long, which got me thinking about running a shortened .308-based case.
I necked a .308 case up to .35 and started test fitting. A 200gr TTSX was too long (even after clipping the tip) so I trimmed the case to land at 2.38" COAL, which feeds from the magazine.
From there, it clicked.
I prefer monos, and Hammer offers a 140gr bullet that fits this concept perfectly.
I worked with Dave Kiff at PTG to design a reamer, with the goal of using standard .358 Win dies. After a few iterations, we landed on a final design I’m really happy with.

Specs:
- Starline .308 Match brass (SRP), necked to .358
- Trimmed to 1.90"
- 140gr Hammer bullet
- 2.40" COAL
- Bore rider/stepped throat

The goal is to push close to .358 Win performance out of my 18.5'' compact, lightweight, Mini action.
We’ll see how it performs this season, but I’m very excited about how it is all coming together.
Still waiting on my reamer to arrive but have:
- Starline 308 Match brass
- CCI/Federal SRP magnum/BR primers
- X-caliber barrel
- NECG banded front sight
- Talley QD rings and removeable peep sight
Will post photos of progress and completed project when finished and bring y'all along for the load development portion this summer. As stated, I'm very excited about this compact little powerhouse I'm putting together and can't wait to hit the hills with it this August.
Photos of my Mini in current form and the dummy round I sent in to PTG for pulling final dimensions for reamer design.

@Wilkup
Sounds interesting.
What velocities are you expecting and what powder will you use.
The stubby little 225 gn Sierra spbtgk would be a nice cup and core for the velocity you will get and give you a lot of cheaper practice. It would also be a good game bullet in the velocity parameters you might get 2,200-2,300fps in my estimation.
Enjoy your experiment and keep us posted.
It's rifle looneys like us that keep things interesting.
Bob

 

[Bob Nelson 35Whelen]

Well I would say a 35 WSM is a wildcat, but creating your own cartridge and making brass is a whole ‘nother level!

@wildwilderness
Creating your own cartridge is fun.
Sometimes a waste of time because a factory round will do the same or better
Sometimes it turns out to be a dud
And sometimes it exceeds your expectations
Fortunately my 25 on a 303 British case fell into the last category. Ain't no flies on a 25 cal you designed yourself gives you 3,600+ fps with a 100gn projectiles and uses just 58 gn of powder.
I don't know what pressure but load from a disc says 52,000cup and I get nice rounded primers, minimal case head expansion and long case life plus easy bolt lif so I assume all is well.
Wildcating is a great be it somewhat expensive hobby that only the brave ( read true rifle looney) undertake.
Bob

 

[Wilkup]

@Wilkup
Sounds interesting.
What velocities are you expecting and what powder will you use.
The stubby little 225 gn Sierra spbtgk would be a nice cup and core for the velocity you will get and give you a lot of cheaper practice. It would also be a good game bullet in the velocity parameters you might get 2,200-2,300fps in my estimation.
Enjoy your experiment and keep us posted.
It's rifle looneys like us that keep things interesting.
Bob

Going off the Hammer load data, CFE-BLK is going to be the hot powder with this 140gr Stone Hammer and they're claiming 3175' from a 24'' barrel with the top load.
I was notified my barrel will actually be finishing at 19.5'' and not the 18.5'' I intended due to the NECG sight I purchased. All good. With the stepped throat and more or less equivalent case capacity, I'm guessing I should land in the 3100+ fps range with this little cartridge.
I'm not sure the 225gr Sierra will fit in my rifle. This wildcat was designed and built around the Howa Mini Action and 140gr Stone Hammer. I am limited to 2.40'' COAL.
I am definitely a rifle looney lol

 

[Bob Nelson 35Whelen]

Going off the Hammer load data, CFE-BLK is going to be the hot powder with this 140gr Stone Hammer and they're claiming 3175' from a 24'' barrel with the top load.
I was notified my barrel will actually be finishing at 19.5'' and not the 18.5'' I intended due to the NECG sight I purchased. All good. With the stepped throat and more or less equivalent case capacity, I'm guessing I should land in the 3100+ fps range with this little cartridge.
I'm not sure the 225gr Sierra will fit in my rifle. This wildcat was designed and built around the Howa Mini Action and 140gr Stone Hammer. I am limited to 2.40'' COAL.
I am definitely a rifle looney lol

@Wilkup
For its weight the 225gn Sierra is a very short bullet compared to others. If you can get hold of one maybe worth a look.
Bob

 

[Wilkup]

@Wilkup
For its weight the 225gn Sierra is a very short bullet compared to others. If you can get hold of one maybe worth a look.
Bob

You seem to be a devout 35 guy. Any chance you’ve got some of those bullet lying around?
If you could tell me the bullet length and also estimate the length from tip to Ogive it’d let me know if it’s a viable option for my shortened cartridge.
Using Gordon’s Repoading software for 358 Win but changing values on case length, capacity, and COAL, I can theoretically use 38.2gr of CFE-BLK in combination with that 225gr Sierra bullet for 2311fps in my 19.5” barrel.
In my experience with every other round I’ve reloaded for, Gordon’s software has been extremely cautious with regard to pressure and optimal velocity, but provides a safe way to begin load development.
I have about 15# of Trailboss and 5,009 147gr XTPs I plan to load in this cartridge as a fun, fooling around, plinking load too. Should be a good time this summer!

 

[Wyatt Smith]

It looks like it would be similar to a 300 savage necked up to 35 with a shorter OAl. An interesting project for sure, I’ll follow with enthusiasm.

 

[Wilkup]

It looks like it would be similar to a 300 savage necked up to 35 with a shorter OAl. An interesting project for sure, I’ll follow with enthusiasm.

Very close!
The difference/advantage being I can use standard 358 Winchester dies rather than expensive one-off customs.
I've shot wildcats over the past 15 years and custom dies have always been $250+. I picked up a standard RCBS 358 Win 2 die set for $48.
I also wanted to use the Starline 308 Match brass for convenience and affordability. Basically a "working man's" wildcat design

 

[Bob Nelson 35Whelen]

Very close!
The difference/advantage being I can use standard 358 Winchester dies rather than expensive one-off customs.
I've shot wildcats over the past 15 years and custom dies have always been $250+. I picked up a standard RCBS 358 Win 2 die set for $48.
I also wanted to use the Starline 308 Match brass for convenience and affordability. Basically a "working man's" wildcat design

@Wilkup

A seli of 225grainers L-R
225 Woodleigh RNSP
Sierra game king
Woodleighs PPSP
220gn Atomic 29 mono

Sierra 225gn spbtgk looks like base to start of office is around 14mm velocity parameters 2,800-1800fps

Woodleighs 225gn RNSP give / bullet taper starts at less than 10 mm by the looks of it.
Hope this helps you. Velocity parameters 2,600-1800fps
Bob

 

[Wilkup]

@Wilkup
View attachment 763024
A seli of 225grainers L-R
225 Woodleigh RNSP
Sierra game king
Woodleighs PPSP
220gn Atomic 29 mono
View attachment 763025
Sierra 225gn spbtgk looks like base to start of office is around 14mm velocity parameters 2,800-1800fps
View attachment 763026
Woodleighs 225gn RNSP give / bullet taper starts at less than 10 mm by the looks of it.
Hope this helps you. Velocity parameters 2,600-1800fps
Bob

I didn't realize this when I made my last post, but Gordon's Reloading provides the 225gr Sierra SPBT bullet data - Length (1.1575"), BC (0.364), and required seating depth based on my 2.40'' COAL!

Looks like 2300-2400+ fps would be feasible with this little bullet. I still plan on favoring the 140gr Stone Hammer for higher speed and monometal performance, but if I can source those Sierras for a decent deal they'll make great plinking bullets or some pretty gnarly HEAVY, brush busting thumpers.

Gordon's is showing recoil stays the same regardless of bullet used. It's going to be ~20ft-lbs in my 7lbs rifle, whether I'm pushing a 225gr at 2300' or a 140gr at 3100'.

 

[Bob Nelson 35Whelen]

I didn't realize this when I made my last post, but Gordon's Reloading provides the 225gr Sierra SPBT bullet data - Length (1.1575"), BC (0.364), and required seating depth based on my 2.40'' COAL!

Looks like 2300-2400+ fps would be feasible with this little bullet. I still plan on favoring the 140gr Stone Hammer for higher speed and monometal performance, but if I can source those Sierras for a decent deal they'll make great plinking bullets or some pretty gnarly HEAVY, brush busting thumpers.

Gordon's is showing recoil stays the same regardless of bullet used. It's going to be ~20ft-lbs in my 7lbs rifle, whether I'm pushing a 225gr at 2300' or a 140gr at 3100'.

@Wilkup
Those 225s are only 100fps slower than full power loads in the 358 win so would be awesome out to 200 yards.
Bob

 

[Wilkup]

My reamer just showed up from PTG!
Just waiting on the action to come back from LRI with the opened bolt face and adjusted feed rails!