Ok got a martini cadet action and a 1:8 twist barrel coming. Suggestions?

[beltfed]

Bigslug,
You will not regret going to the 357Mag for your Cadet.
I love mine. Get a 14 twist barrel..
beltfed/arnie

[barrabruce]

Well my 300 blk dies come and I have bought some brass.
Machined off 70 thou off the fls die.
The mag brass can just fit in the base of the die now.
But I can use the seating die to start the process if needed.

Still waiting for a case holder but using the vice I have reformed a few cases.
I want to keep the neck full length for cast bullets.

I will have to sort out that depth with the reamer if it ever comes to see what it needs to be.


So far things are starting to come together as planned.

The 310 rock may come into fruition yet.

If things go south the barrel can be always chopped back and re - chambered.

[John Taylor]

You may need to bush the firing pin when going to a higher pressure round.

[Jedman]

barrabruce, I don’t mean to insult you as I know you hav done these things before but I just thought I would mention, when you make some dummy cases with your 357 brass remove the rim on a couple to use as a gauge when you ream your chamber. Basically if you are forming the brass and getting a good full formed shoulder you want to set the headspace close off of the shoulder on your dummy shells.
Being you will be making the rim recess with a lathe bit instead of the reamer cutting it , I would do that last.

I found on my 256 Win mag chambers that I reamed them with a factory reamer and stopped as soon as the rim recess was just a smidge past flush with the breech face with the brass I was using. Then after firing some new formed cases that were sized with RCBS dies and comparing the fired cases to just sized cases I could see with my eye that the shoulder on the fired cases looked forward of just sized.
So I took a couple of resized brass and turned the rims off and used them to check my chamber and found that when the rimless dummy cases were in the chamber where the case shoulder was the bottom of the case was .010 deeper than the breech face.
So the reamer manufacturer cut the reamer to their standard and RCBS was to a shorter standard by .010 so now when making new brass or resizing fired cases for that chamber I need to set the sizing die with a .009 feeler gauge between the shell holder and the bottom of the die and be able to pull the feeler out with quite a bit of resistance while holding the ram on the press as high as it will go.
I have made Many wildcat cartridges the same way by shortening a standard sizing die to where the base is the correct size for the brass I want to use then make a couple of dummy cases to use to set headspace.

Jedman

[Antietamgw]

[QUOTE=Jedman;5294739]barrabruce, I don’t mean to insult you as I know you hav done these things before but I just thought I would mention, when you make some dummy cases with your 357 brass remove the rim on a couple to use as a gauge when you ream your chamber.

Jedman,
Thanks for posting that. I'm soon going to cut a chamber for a shortened rimmed Blackout. That's a handy tip to confirm that the shoulder in the chamber is where you want it.

[blackbahart]

the version of my 300BO rimmed I built last year on a martini using 360 DW brass which is 1.4" long with a gain twist barrel
pic of cases

[barrabruce]

Thankyou jedman yeah I can see that clearly.
No offence here.
I like all opinions.

If 360 Dan Wesson brass was more common here I could just use that.

I think by having it done a bit short will stop someone from chambering high pressure blkout rnds in the rifle.
I’m not sure how much of a difference in case capacity it will be.

I think 30 badger loads would be o.k.
I have some 30-20 load data so that could be a starting point.
A couple of 30 Paxton loads as well for adi 2205 and adi 2207.
Not trying to duplicate the blkout with 50k psi loads or anything ridiculous like that.

[slug]

I have a Cadet reformed to .357 and it works OK.
The round has to go straight into the chamber, but the lever wants to close a bit from full open.
I have to hold the lever full open with my pinkie to start the round with my thumb.
It's a little awkward with my small and arthritic hands, but still do-able.
A bottle neck cartridge would be easier.

Several decades back, I was told that It's quite easy to modify the rifle so it stays fully open, but I can't recall the details.
I'll have to Google it.

[brstevns]

A few years ago a local Gunsmith turned my Cadet into a nice 223Rem. Said he had a heck of a time on the extractor but he got it figured out and it runs great.

[barrabruce]

Best I can do at the moment.

Waiting for stuff still.

Wistfull thinking mode still.

Obviously the 32-20 case is the magnum.

The 310 Ackley Improved magnum ought just burn up the country side.

Be good for poleaxing big pigs at least 200 barstool paces..

Think I’m making a rimmed wildcat of a rimless production cartridge; that was a rimmed wildcat originally..

Like 40-50 years ago at least.

Brass and bullets should be around for a while.

I could scrounge up 223 or discarded 300 blk cases and remaster them and use a screw driver to extract if things get real bad.

Ha

[M.A.D]

.

My dream gun for deer hunting was a Cadet-sized Martini, bored out or re-barreled & chambered for the .256 Winchester Magnum, but could never find a suitable action (or the $$ )

Bullpup Martini in 256..... Loving it

[barrabruce]

MAD
I’ve seen that before.
Have you a picture of how you load it?
Does the top of the butt lift up to load or come off for cleaning.
Nice way to have a long barrel in a short gun if I’m thinking right.

[barrabruce]

Well I got the barreled action back from the gun plumber.
Barrel is 18" long as I thought it would be long enough to not ring my ears with a light load, long enough for full powder burn and nibble enough caring around through some scrub.
Asked him to leave it rough finished so I could smooth it up for bluing.

Not finished at all but I wound a bit of wire around a short fore-end and clamped a red dot to it.
Headed down the range to test it out.
Not real light but not to shabby either

Short forend

Full length fore-end.
Playing with bluing

Looks something like this in it’s post apocalypse dressing at present.


It shot well.
Light little wand really.
I could hit a coke can pretty well off hand at 50 yards.
I had about a 4" group of different loads and bullets.
Checked for base of case swelling with a mic and length with a vernier.
More positive playing is yet to be done.
The red dot was good a 50 but I had trouble seeing the can to shoot it.
The gun pivots just forward of the trigger and comes up fast .
I may test a long skinny forend on it as it may be better off a rest to shoot for a slower shot.
Scope and or irons to be determined.
Thanks for looking.

[barrabruce]

Well this time I shot some groups and collected some data.
Started off with the Lyman thrower at 1.6 grains and cranked out the top plate till it started to shoot good.
Took a few samples home to weight later.
All these were shot with a red dot at 50 yards and 3 or 4 bullets used.
things first got going at 1.9 grains bulleye. Speed unknown.
next node seems at 2.6 grns bulleye and the Lee soup can.
#3 node which is about 3.2 grns bulleye and 170 gc fp.
is the bees knees so far with the 170 gn pbhp
But the 150 hp hunter didn’t like it and some tipping was involved.

I think the point hits the rifling but the base is hang out there in the breeze causing steering problems.
But the ‘ye ‘ol Lyman 241 150 grn pbrn loves it..
Well it was hot and the bullets were slumping if you left them on the dash of the Ute.
I could just about dip lube them in the be/vas lube.
For a gun that needs breaking in and a red dot at 50 yards it shows a lot of promise.

My cast bullets are too soft for gas checked loads, so I may paper patch some up and try some adi 2205 I have.
Pistol powders are scarce and primers are becoming elusive at the moment too.

I may have to make a bullet reforming die if I can figure out how too.
Plus a squillion other tools for loading.
Like a proper straight line seater and such.
Remade a 30 cal Lee die set for it and a primer seating tool, but still using my original 30 cal de primer tool.


All in all not too shabby as things are at the moment.
Barra

[AlanF]

Very nice. What a cool project. Look forward to seeing the finished product.

[Rapier]

357 Super Mag and the 7 TCU have exactly the same case capacity. Can use the same powder, mainly 4227 for cast. The 30x357 Mag should be about 66% H2o capacity and 4227 should work well, as 4227 also works well in the 30-20 with 200g cast.

[barrabruce]

Thanks rapier.
I used an equivalent of adi 2205 at 17.5 grns and 110 jackezed rn and they had no pressure signs and at the web showed no sign of growing and primers showed no high pressure signs.
Extraction was easy.
The zip tie and super glued scope became self rotating so no groupings.

What is the 30-20 200 grn load you use?

I have done a little more work towards the end product and I’ll see how it performs soon I hope.

[barrabruce]

Things have gone off on their own path and some bugs worked out other things to try.
Made a front sight to try , and see if it works or not.
May put a pica tinnyrail on it yet just to make it real ugly.


Need to re-blue but will wait and see first.
May try an extended stepped over the back scope attachment and then I’ll need a pegged cheek piece riser on the stock for a cheek weld.
Never ends.
To many options.
Ha one day I’ll have it sorted.
Just need to cast a few more bullets and finish off the mess I’ve made of it so far and test it out again.
The longer for-end should give me a more solid format for longer range shots then just standing off hand.

[barrabruce]

Well it’s blued.
Finished.
Done.
I’ll see what I can scrape up as in primers and powder and bullets to burn in it and see how it goes with some real loads.
I think I’ll call it my "bubba cadet"
Suitable name in more ways than one.
If I put a full length pic rail on it I can always claim it as some
Strange offspring of a wild party in my gun safe.
When some evil black taticool mall ninja gun came for a stay over for a while.

[Mike H]

Always good to see the job finished,hope you can find enough primers and powder to give it a fair test.The 1-8 twist barrel should be interesting with heavy projectiles.
Hope the New Year goes well for you.
Mike.