310 Martini Cadet reloading tips

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310 Martini Cadet reloading tips

Post by Rabbit99 » 29 Jun 2020, 9:40 am

Hello, and thank you for allowing me to join the forum.

To start, I live in California, USA. I have an outstanding original condition, fully functioning 310 Cadet. Ammo is a little tough to get, but I am going to be using the 32-20 brass and I found bullets that are alloy. I have someone making the ammo for me, but I might be better off making my own.

A few years back I purchased the cadet complete set of dies. They are simplex.

For reloading, I would like some tips, I am new to this, but would like any and all assistance.

The dies are SIMPLEX.
Using the 32-20 brass

Do I need a specific reload press?
Do I have to modify the brass?

Better Ideas?

Thank you again.
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Re: 310 Martini Cadet reloading tips

Post by No1Mk3 » 29 Jun 2020, 4:51 pm

G'day Rabbit99,
Some Cadets will accept 32-20 brass, but most will not due to rim thickness so ypur mate may need to thin the rims a little. The original thickness was 0.038". Another issue is base diameter and you may split a few cases while forming them. The case should also be trimmed to 1.075" Your dies if they are Simplex Master series will fit any common press with the 7/8th x 14 TPI thread but if they are the Super Simplex series the thread is 5/8th x 26 TPI and you will need an adaptor which your mate with the lathe would be able to turn up or you can contact Simplex here in Oz at simplexreloading.com.au, Cheers.
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Re: 310 Martini Cadet reloading tips

Post by marksman » 29 Jun 2020, 9:47 pm

G'day rabbit99
you can get the 310 cases from here
https://www.australianoncefired.net/htt ... le%20Brass
l do not reload for that case but there are a good number of guys on the forum including No1Mk3 who will help you out with there knowledge
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Re: 310 Martini Cadet reloading tips

Post by No1_49er » 29 Jun 2020, 11:02 pm

Hello Rabbit99.
Couple of things to add to the above replies.
The correct projectile (cast) is of the "heeled" type, similar in style to 22LR. Cast Bullet Engineering makes a number of moulds for the Cadet https://www.castbulletengineering.com.a ... /310-cadet The original was 120grain.
I have had no experience with the Bertram brass (I have some original Kynoch that get recycled :) ) but have heard from colleagues who have, that the case mouth thickness is somewhat excessive and ideally needs neck turning else the projectile is "shaved" quite seriously when seating.
Hope that's of some help.
And, please don't take the route that many others have, and cut the chamber to 32-20. There's enough of them around without devaluing a fine Cadet training rifle. I you feel like having real fun, track down a 297/230 trainer, the predecessor of the 310. Bottle neck, centrefire, black-powder (around 6gn) 37gn cast, similar performance to the current 22LR.
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Re: 310 Martini Cadet reloading tips

Post by gunnnie » 30 Jun 2020, 8:55 am

Welcome to the group mate. Good to see another devotee of the Cadet 310.
As others have said, the 32-20 case has larger dimensions than the 310. It was a common thing here to have a Martini Cadet chamber modified to accept the 32-20 as the brass was more available, plus Bertram brass is also known for dimensional inconsistencies.
I have a Cadet which has a modified chamber. The rim recess had been deepened to accept the thicker 32-20 rim and that was all. The 32-20 case had to be shortened to 310 length.
As others have said, you'll need to thin the rims on the 32-20 to replicate the 310 case. When you do this, take from the front of the rim, not the base. If you file the base to thin the rims, you will reduce the primer pocket depth. This'll result in the primer sitting proud, which is not a good thing in a rising block action!
Regards projectile choice, a lot will depend on your bore diameter. The early production Cadets were solely BSA therefore bore diameter is consistent, nominally .314 - .316". Later production saw Greener producing barrels, leading to widely varying specs. Greener bbls can be up to .323" diameter.
The Greener bbls led to the introduction of the 128gn heeled projectiles without production modification of the brass. If you have a Greener bbl all you need do is deprime your fired cases in a universal deprime die, don't re- size, prime the case, add powder & just press the heeled projectile into the mouth of the case till the case mouth butts up against the full shank of the projo.
If a smaller diameter bbl then you'll be resizing the fired brass. Though I do know of a few shooters who just press the projo into the sized case. Some will crimp. It'll all depend on what they find suits their particular rifle. In these instances a lot of Cadet 310 shooters here don't use heeled projo's.
I don't use heeled projo's in two of my Cadets. Powder wise, I prefer using pistol powder in my 310 loads though a lot of guys use fast rifle powder. As well, there are devotees of small rifle primers, I use pistol primers.
Any questions or further help you need mate, just ask away. Happy to help mate.
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Re: 310 Martini Cadet reloading tips

Post by Daft » 03 Sep 2020, 1:40 am

Got me sorted for reloading the 310
.17 cz air rifle
Cz 455 22lr
La 102 .223
Gustav M96 6.5x55
1918 lithgow smle .303
Cz 550 .308
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New South Wales

Re: 310 Martini Cadet reloading tips

Post by marrinup » 21 Feb 2021, 7:20 am

I have a Martini 310 that is used at our club comps, mine shoots very well and has won gold medals out to 75 m, took a while to get the loads right, I cast a 122 gn proj of lead, heeled of course, case filled with 9 gns of AR2205 and a thin card board cookie that has been boiled in 100% bees wax on top, this slight powder compression ensures all powder is burnt and provides excellent accuracy. Proj is coated in liquid alox and which does not lead the barrel, extractor is so strong that it chucks brass over my shoulder.........very nice to shoot and is a fine bit of vintage kit.
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Western Australia

Re: 310 Martini Cadet reloading tips

Post by LawrenceA » 23 Feb 2021, 6:45 pm

Before you get carried away trimming case rims, see if they fit.
A surprising number of cadets will take the thicker rim. One maker was known for it but I cannot remember which.
You will find that 310 cases can vary in length as well and the rifle throats and bores can vary considerably.
If you want any degree of accuracy I would suggest you cast the chamber and throat and figure out what you need to aim for (no pun intended).
Ideally the bullet should a coupla thou over the throat size.
Have fun. They are a great little gun.

Take a look here to get you started
One well placed shot is all it takes.
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