.310 Martini Cadet question......

[3006guns]

I've had a little Martini action Cadet rifle for years, but never shot it much because stamped on the barrel is "32-20". Now, we all know that the 32-20 bullet is far too small for the Cadet bore, so I just put it aside for future study. A shame too, because the bore is gorgeous.

While rummaging through my pile of stuff I found three boxes of Kynoch .310 ammunition, so I compared one of them to a 32-20 and discovered that:

The 32-20 case is longer than the .310.
The 32-20 is a mild bottleneck, compared to the straight taper of the .310.
The 32-20 case is smaller in diameter at the mouth by quite a bit.
Bullet diameters are, of course, different.

Now, here's my question. This little rifle was no doubt one of the imports back in the early 1960's, but wasn't sporterized or changed other than the barrel marking. I've seen countless articles stating that a 32-20 reamer was run into the chamber in order to make them more "saleable" here in the U.S. So ASSUMING this is true, how in the world did they get the reamer in there? Remove the barrel? Doesn't look like it at all, yet the 32-20 AND the .310 will both chamber. If indeed they reamed it, it would only lengthen the chamber somewhat but not change the contour. In other words, the .310 bullet might have to travel a bit to reach the rifling, but it will shoot. For that matter, I could shoot 32-20 in order to fireform the case and reload with the correct bullet, assuming the case didn't split (that's an awful big expansion for that little case!).

If the above is true, I can still load and shoot the .310 Cadet cartridge with some hope of accuracy. All I would need is a mold for the correct diameter heeled bullet which is available from Australia I believe.

[JeffinNZ]

Your best bet is to do a chamber cast and establish for sure what you have. You are 100% correct that regular .32-20 projectiles are lacking in diameter for the .310 Cadet barrel. The ".310" is the British nominal bore you see. The actually throat/groove will be nearer .320 when you measure it.

Jim at CBE in AU does a wonderful range of .310 Cadet heel bullets. Last count I think there was seven which is unheard of. His site is www.castbulletengineering.com

[3006guns]

Thanks Jeff........I'll take your advice and do a chamber cast and start looking for a mold. I'm really fond of this little rifle as it's still in "full military" costume and it's about time I started to play with it.

[herbert buckland]

you might be lucky and find the chamber has not been reamed,about 1/2 the 310 cadets will acept a 32-20 without changing the chamber,the chambers on these have no sholder ,they just taper from chamber to bore so even the ones that had to be reamed ,the reaming was very minamal and they shoot 310 just fine

[Multigunner]

how in the world did they get the reamer in there? Remove the barrel? Doesn't look like it at all,
A friend who installs short chambered M1 Carbine and Garand barrels told me he cranks the barrel in, then used a reamer that screwed onto a special rod run in from the muzzle, giving it a turn or two at a time then checking headspace with bolt inplace, he could then get optimal headspace for the individual rifles.

Perhaps a similar set up was used.

[3006guns]

After thinking about it, I'm going to disassemble the action so I can get a good look at that chamber......kind of difficult to tell if anything was done with that breech block in the way! The comment about NOT reaming struck a chord. I remember that also, so with any luck maybe the caliber stamping was the only thing done (fingers crossed).

Again, it's such a cute little guy with its full "military" stock and kangaroo stamping it just begs to be shot! Now if I could just find a bayonet, I could charge some miniature "fuzzy wuzzys"..........

[JeffinNZ]

Now if I could just find a bayonet, I could charge some miniature "fuzzy wuzzys"..........

They don't like the cold steel up 'em Captain Mainwarring!

[smlekid]

+1 on the CBE Moulds for the cadet I use the .320 diameter and 120gr mould in my 2 cadets they shoot very well with that boolit
I trim my cases to 1.050" (the shortest in the couple of hundred Bertram cases I have)
I use Blue Dot and Winchester 540 in my rifles
with the above boolit the alloy I am using drops at 110gr I am getting 1400 fps and excellent accuracy using 6.5grs of Winchester 540 and SR primers
7gns of Bluedot seems to shoot well but I haven't had them over the chrony
some have had good results with Unique but I think it a little fast in the rifle length barrels

[curator]

I have one of the .32-20 Cadets. Accuracy with factory .32-20 ammo was poor until I got a proper .310 Cadet mould from CBE. I load these in unsized, firefromed cases over 4.8 grains of Unique and get excellent accuracy. I lube then with LLA whcih helps keep the boolit from falling out when the loaded cartridges are handled. Actually it turns out to be a lengthened .310 Cadet case with a slightly thicker rim but easier to buy over the counter. No difference in accuracy compared to my unmodified Cadet but the .32-20 case needs a bit more powder to achieve the same velocity due to its extre case volume.

[Multigunner]

I'd read that during WW2 these were sometimes issued to guards at factories and warehouses, and a higher velocity version of the .310 cartridge with balistics similar to the US .30 carbine round was developed to give the little rifle more punch.

[smlekid]

the CMF (Civilian Military Force) were issued 310 cadet rifle in WW2 for the pending Japanese invasion (YIKES) No1 Footscray (MF Headstamp) ammunition factory loaded a 120gr FMJ for the Cadet it was a pointed round as the lead boolit was against a treaty (Hauge?)

[PAT303]

I have a cadet with a 32-20 chamber and load the Lee 185grn 8mm boolit over 15grns of 2207(4198) and it shoots really well out to 200m. Pat

[Argus]

I have recently acquired a Greener 310 Cadet chambered for 32-20 (barrel stamped). Early test results with 310 rounds is proving encouraging. I am loading 9.5gn of AR2205 behind Hawkesbury River Blackhawke 128gn .323 heeled boolits. I am using both old once fired Super brass, and new Bertram brass. 10 rounds in 1.5 inches at 50M is the best so far. Next opportunity will be to shoot this load over my chronograph, and try 9gn and 10gn of AR2205.

Interestingly I have some 32-20 brass and I cannot get it more than 75% into the chamber.

[chrispy]

I have recently acquired a Greener 310 Cadet chambered for 32-20 (barrel stamped). Early test results with 310 rounds is proving encouraging. I am loading 9.5gn of AR2205 behind Hawkesbury River Blackhawke 128gn .323 heeled boolits. I am using both old once fired Super brass, and new Bertram brass. 10 rounds in 1.5 inches at 50M is the best so far. Next opportunity will be to shoot this load over my chronograph, and try 9gn and 10gn of AR2205.

Interestingly I have some 32-20 brass and I cannot get it more than 75% into the chamber.

Try 3.5 to 4.5 grains of AP70n behind a CBE HB boolit. I settled on 3.5gn for a nice moderate load. Pill sized to .317.

Chrispy

[old turtle]

With out question slug the barrel (pure lead slug)to check dia. I have one which is.316. RCBS makes a mold for this round. The lead boolit has a heel that goes into the brass case. Like Chrispy 32-20 would only go into the chamber about 75%.

[smlekid]

I'd give up on 2205 in the cadet AP70 and AP100 are the most popular powders at my club
I use Winchester 540 it makes a great load accurate easy extraction and no leading with the 128gr Blackhawke and my own cast CBE 310 boolit (LLA lubed) chrony around 1350fps
I have been playing with some Bluedot it looks like it will be a good powder as well
most people at my club are loading 4-5gns of AP70 my rifle wont digest 4gns which is why I went looking at slower powders I believe that AP90 (if it was still made :() would have been just about perfect

[DIRT Farmer]

Strange but I never checked my Cadet barrel. I was told when I bought it it was a 32-20 so I bought some brass and loaded the Lyman 313 SWC 85 grn and 4227. It shot well enough to hunt squrrils (sp) so I just had at it. It has always been a great walking about rifle. Full dress except for a home made front blade.

[chrispy]

'Ironbark' ammo made a recreation of the WWII load using a Taipan 316 JHP with 7.8gn of 2205 behind it. Shot really well in my cadet, but split a few cases.

Chrispy

[New2daGame]

Hey all new to this thread. I just purchased my first martini 310 cadet rifle in 310 cadet. I have heard that you can simply reload the cases by hand but am not sure it this is good or even safe. need some advice and i have never reloaded rifle or pistol ammo in my life. Can you guys help with an inexpensive propisition to get me in the "game" so to speak. I would like to do it the simplest way possible without having to build some huge reloading room. hand loaders seem interesting and simple. Not sure if they offer a hand loader for the 310 cadet but you all should know. Thanks

New

[swamp]

New2daGame,

310 not the best to learn reloading with, but will try to get you the basics.

First you should search this forum for everything you can find on 310 Cadet. Also try thr Britsh Military forum. There is a wealth of info on both sites. After you digest all the info then it is time to start.

You will need to slug the bore to find out just what size it is. The 310 runs around 323 groove diameter. The booliit used in it is a heel type. That is there is a short sahnk that seats into the case and the rest of the boolit is the same diameter as the case.

Cases are available from Bertram Brass out of Austrailia. That is what I use and they have been very good. It is also possible to make them fro 32-20 brass.

To do the actual reloading you will need a punch to deprime the case and a way to reprime. You might be able to do it with a 32-20 Lee Loader.

Once you have got the brass fireformed( fired in the rifle) you will not need to resize.

There are guys on here that can and will lead you through this who can explain the process better than I, but that is the basic.

The warning I will give is that once you start shooting the Cadet you will be hooked. They are a fun little rifle. You just have to learn the quirks.

Also you will get hooked on reloading and casting boolits so be ready. It is relaxing and frustrating at the same time.

If I didn't make something clear or you have more question please ask. No way to learn without asking questions. Some one here can answer all the ones you have.

If you decide too try I can send you some of the proper boolits for the Cadet. I have a mould for it, as I feed a pair of them.

Once you know all that's involved the it is time to discuss loads.

Welcome to the forum. Lots of info here and a good bunch of people.

swamp

[Argus]

Go have a read of the thread entitled '310 Martini Preliminary Results' on this website.

[456eec]

To make .310 cases from .32/20 cases just have someone with a lathe machine the front of the rims to reduce them to .045". Then trim them to length and full length resize with .310 dies. The question is what length? Someone on Wikipedia has quoted 1.075" but I can't find any actual published length in any of my books. If you want to use this length and use a Lee trimmer the pilot for the .32 H&R Magnum is exactly that length. Some Kynoch factory ammo I have has cases at 1.106". Most older commercial cases and Bertram cases are shorter at around 1.065 but vary greatly. I've found I can trim the .32/20s to 1.2" and using CBE .320-120 mould they chamber, shoot great and extract well with minimum freebore. Obviously other rifles are different but you could gradually trim them a little and try them to get the maximum length with your particular projectile.
In answer to the original question re .32/20 rechambered rifles, the reamer would just lengthen the chamber and make the rim rebate a bit thicker. You should be able to use heeled bullets at around .320" in normal .32/20 caseswith good results.

[SSBN620]

Had good results yesterday with 4.0 gr of Trail boss in 1.075" Bertram cases with .323" 120 gr heeled cast bullets. Should say though, even though the rounds grouped 1-1/4" group at 50 yds, the group was 8 inches above the bull.

[LITTLETOM]

I have a 310 that has been rechambered to 357/8mm which is a 357 necked down to 8mm it pushes a gas checked 175 lead bullet up to 1800 fps--and plain base cast up to 1400 fps with 1/2 inch accuracy at 100 yrds--all this is accomplished by using the origional 310 1in12 twist barrel which slugs out to 320 and of course 8mm is 321 to 324 depending on mold-really a nice shooter and even powerful enough for deer and blows the heck out of jack rabbits any questions

[JMtoolman]

ON my 310 i use a RCBS mold with a heeled bullet sized .324. Shoots very good! Even killed a small buck with it years ago. A real fun gun! the toolman

[gnoahhh]

I guess I'm one of the lucky ones. Mine accepts .32/20 ammo (I never checked it to see if it was re-chambered) and is devilishly accurate with .314 diameter lead bullets. I haven't fired it in years and have a project for it in the back of my mind. (I'm thinking .357 Mag or Max with a classic pistol grip stock and tang sight for a light handy deer rifle. The first thing I'll do is drill a .250" access hole in the back of the receiver to allow the cleaning rod to pass through to clean from the breech. I did that to two Martinis back in the 80's- 1 Hornet, the other .218 Bee. I got the idea from the hole that's there on small frame Martini .22 target rifles.)

[RonE]

From the Ammo Guide site: Case length - 1.120" Max Over All Length - 1.6" Bullet Dia .323"

Nominal preformance: 120 gr Boolit @ 1,200fps

--------------------------------------------------------------------------------
Also known as the .310 Greener, the .310 Martini Cadet was introduced in 1900 for use in small Martini training rifles, most prominently in Australian military and police services. After WWII, many of these rifles would find their way to the United States to be sold on the surplus market and find limited success as a small-game hunting round. .32-20 Winchester brass can be used to form .310 Martini Cadet cases.

To determine their commercial viability if rechambered, some of the original Martini Cadet rifles would be pressure-tested with proof loads as high as 60,000 psi . As a result, remarketed Martini Cadets were available from the Winfield Arms. Co. and Klein's Sporting Goods in Chicago, in more practical chamberings for the day, including the .357 Magnum, .22 Hornet, .44 Magnum, even the .32 Winchester Special.

Barnes 'Cartridges of the World', 9th Edition lists a .310 Cadet load of 6 gr. blackpowder pushing a 120 grain lead bullet at 1200 fps with 385 ft-lbs. muzzle energy.

My Cadet Rifle is chambered for the .32 Winchester Special but I am converting it to a single shot varmit rifle in 5.6X50R so I will soon have a cadet barrel with sights chambered in .32 Win Special for sale. Should have the project underway next month.

[NoDakJak]

I can certainly attest to the fact that the little flea weight Martini that is chambered to 32 Winchester Special fun is no fun at all to shoot with factory loads. The rifle is very light with a stock not built for recoil. The recoil is not a push but instead just slaps the snot out of you. Cast Boolits loads would be a different matter. Beware the Cadets that were chambered for 44 Magnum. The barrel tenon is only 3/4" and the chamber walls are rather thin. Most of them that I have seen have jugged chambers and that usually stretches the reciever ring and ruins the rifle. My experience with the ones rebored to 357 has been great! One of my better rifles is one that was rebuilt and barreled to 25.20 by Sportco in Australia. It is the only one that I have seen in this country although I do have a Sportco that is modified and barreled to 22LR. This has an unusual cross-bolt safety that is machined into the lever.
A couple years ago I got into a group buy for 310 Martini 120 grain boolits. Lee certainly got my mold right. I trim 32.20 cases and thin the rims. Cases are neck sized in a 32.20 die and mouths are expanded very slightly with a taper punch. The shank size is close to perfect. I start the boolits by hand and finish seating with a press that was originally used for stampng some type of badges. The boolit dosen't have any lube grooves. I simply take a little Johnson Paste was in my hand, stick the loaded round between thumb and forefinger and give it a twist. The wax dries clear and hard and I have not experienced any leading. GreenDot, 231 and Unique seem to be working well but extensive testing is still to come. Neil

[linus]

I have two 310 cadets. The barrel has to be pulled to chamber it for 32-20. My groove diameter is.316. This excludes the standard diameter bullet for a 32-20. So i had a custom mold made for a 100gr bullet by LBT in Idaho. It shoots like a dream. It loves 5.0 gr of Unique or 6.5 gr of AA9.
My other is still in 310. I got cases from Buffalo Arms made from 32-20s and some Bertram as well. The bullet i use is a 120 gr heeled bullet cast from a mold made in Australia by Cast Bullet Engineering. And they make a fine mold. They have to be hand lubed. It shoots well as a soft bullet with 5.0 to 6.0 gr AA9. Others use Unique but I got terrible leading problems with Unique. I hope this helps. if you need more info i can be reached at Linus1943@hotmail.com.

Jim Gilligan

[linus]

I just read your experience with the bullet hitting high at 50 yards. Mine hits about 4 inches high on the lowest sight setting at 50 yards. i love the open rear sight, so i am not going to muck with that. However the front sight is dovetailed in, and it is done so perfectly one can barely see that it is. I found I can't get it out and will try a tool designed to remove dove tailed sights. It might also be soldered in there. and require heat as well. Then I will try a higher front sight in it's place to lower the impact. If the new front sight doesn't match the dovetail slot, I will modify the sight rather than muck up the original slot. That is whenever I get around to it. My other martini is in 310, nd I restocked it and replaced the older type rear sight with a proper BSA tang peep. It shoots just great.

[Jamez]

There was one dealer here in AUS pre-96 that I know of who restamped a heap of the .310s he bought with 32-20 to make them more saleable. 32-20 being easier to get than .310 it made them easier to sell, and since both rounds would chamber a lot of people were none the wiser. Didn't ream the chamber at all.

[Bad Ass Wallace]

There seems to be a LOT of mis-information being posted. 310 Cadet bores by BSA (30,000) were 0.316"dia (Australia must have packed up all the dud ones up to 0.323", and shipped them to America) Later the contract for replacement barrels was won by Greener (10,000)were found to be 0.320" and lacked accuracy. The Colonial Ammunition Co. based in South Australia worked on the problem and developed the heeled bullet. This does not mean to say therefore that a heeled bullet is required for every Cadet.

I own 11 Cadets and only the Greener made one has a 0.321" bore. All the remainder shoot a non-heeled conventional bullet sized to 0.317". (See CBE 120.317)

Always finding shooters confusled by a .310Cadet that has been converted to fire 32/20 Winchester. Firstly, I asked a gunsmith many years ago how this was done when a 32/20 has a bore of .312 and a Cadet .316 or larger. A normal .310 Cadet reamer modified to remove the rim cutter is run into a Cadet chamber then a new and deeper recess for the thicker 32/20 rim is cut separately.

When a 32/20 is fired in this modified chamber, you get a gently sloping case of .310 dimensions but just a bit longer. Reloading is done by using normal .310 dies with a 32/20 (RCBS No.1) shell holder

Left to Right : loaded 310 Cadet, Loaded 32/20 and ready for fireforming.
http://img.photobucket.com/albums/v152/BAWallace/IMG_2478_zps854c0f3b.jpg (http://smg.photobucket.com/user/BAWallace/media/IMG_2478_zps854c0f3b.jpg.html)

This is what I tested in my Cadets back in March 2014 with a 125gn CBE cast bullet. I fired 3 rounds over the chrony then 2 x 10 shot groups for accuracy testing. Everybodies favourite, bloody Trail Boss, was the worst performer in terms of accuracy and it left a lot of soot in the barrel.

AP70 4.5gns 1139,1194, 1210fps
2205 9.5gns 1235, 1261, 1242fps
Trail Boss 4.0gns 1043, 943.6, 955.8fps (Burnt dirty)
AP50 4.0gns 1099, 1108, 1086fps
AP50 4.5gns 1221, 1264, 1230fps (Best and most accurate load)
AP100 5.7gns 1130, 1240, 1291fps (As good as AP50)
Win296 9.5gns 1381, 1400, 1354fps (Max)