BSA Cadet rifle in 32-20, groove/chamber incompatibility.

[stubbicatt]

Learned a whole lot with this rifle. It started life as a 310 Cadet chambered firearm, and sometime in the 50's I hear, it was rechambered in 32-20. Groove diameter measures at 319", so I'm in search of a .320" bullet mould. Problem is, a sample case expanded with a .320" expander plug was a snug push fit in the chamber.

The 310 Cadet used a heeled bullet like our modern day 22 long rifle cartridges. I guess I could experiment with heeled bullets, but not having done that before, I have a reluctance. I would need to have the heel part of the bullet properly dimensioned to be snugly held by the 32-20 case mouth, and haven't actually gotten my noodle around what those dimensions should look like. Not to mention whether the throat ahead of the chamber will accommodate the bullet, as it might be too long.

However the chamber of the 32-20 is designed for something like .314" bullets, which is what I have cast up so far. I do not expect any accuracy to speak of out of the .319 bore.

I took my RCBS 32-40 expander which measures exactly .320" (it is too small for 32-40 in my estimation, and has been replaced in use with a BACO custom expander plug), and ran it in a 32-20 case, opening the neck to that dimension, plus or minus. It fit in the chamber, but it was a snug push fit. It ejected readily. I did this thinking perhaps I can get a .320" bullet to fit and shoot in the .319" bore.

My current plan is to get a .317" BACO expander and a .320" 110 grain mould made for the rifle, and assemble rounds on those dimensions. The concern I have is the tight fit of the test cartridge in the chamber, and whether there will be enough room for the case neck to expand to release the bullet upon firing. I realize my methods of measuring are rudimentary. I may make a chamber casting to see what we have here.

The only other approach I can think of is to remove the barrel from the receiver and have the chamber neck opened up a couple thousandths to accommodate a .320" bullet.

Suggestions? Ideas?

[curator]

I have a Martini Cadet "rechambered" to take .32-20 cartridges as well. You might start with a chamber cast to actually measure the chamber/throat area. The "heeled" bullet cast from BHN 12-15 alloy is the correct one to shoot accurately. I have a CBE mould that casts 120 grain slugs with a short .310" "heel" and a .322" ogive. I tumble-lube these with Lee liquid alox and "thumb-start" them in unsized fired brass cases. RCBS sells a bullet mould for this as well. Lee makes a "factory crimp" die for the .32-20 if you feel you must crimp the bullets in place, but I have found no need to do this with mine, simplifying the reloading process and eliminating the working of the brass cases. Simply re-prime, load powder, seat bullet and shoot. I have been shooting the same 100 cases for about 20 years and have lost only one to the mouth splitting. My favorite load is 4.5 to 5 grains of Unique or Blue Dot powder for a velocity of about 1250 fps. This load shoots to the sights on these fine old guns.

I have helped several shooting friends get their rechambered Cadets to shoot, and a few have had to trim the .32-20 case a bit to get the heeled bullets to chamber properly. Mostly it just works as originally designed, substituting the slightly longer, thicker rimmed .32-20 brass for the hard-to-get .310 Greener cases. I have an original Cadet not re-chambered and making brass for it is a pain, having to thin the rim and shorten .32-20 cases to fit. However, there is no difference in the accuracy of the converted rifle using the same bullet loaded as above.

[Outpost75]

I used the RCBS 32-120 Cadet heeled bullet in mine.

[swamp]

I have the heeled boolits for the Cadet. My guns are in the original 310. If you would like to try some let me know. How close to Denver are you?
swamp

[Ballistics in Scotland]

The concern I have is the tight fit of the test cartridge in the chamber, and whether there will be enough room for the case neck to expand to release the bullet upon firing. I realize my methods of measuring are rudimentary. I may make a chamber casting to see what we have here.

It is easy to say that you would be OK with this sort of fit, in a strong action and with a relatively modest powder charge and cast bullet. I think you most likely will, but at the very least you should work up to it from low charges, and check every loaded round very carefully in case you get an oversized bullet or a case which is thick in the neck.

Back in the 1920s there was an experimental issue of National Match .30-06 ammunition with tinned cupro-nickel jacketed bullets. It was extremely good at preventing serious metallic fouling. But I believe it was Col. Townsend Whelen who found out that it drastically increased the bullet pull, to the extent of breaking the test machine.

Nonetheless this didn't cause accidents. What did was the members of the intellectual classes who, despite instructions to the contrary, lubricated those bullets with grease. When things happen quickly enough, a liquid, or grease, behaves very much like a solid, and it was enough to cause breech explosions. This suggests to me that bullets don't pull out of the case at all. The case is expanded to release them, like blowing into a rubber glove, and you don't leave much room for this to happen.

People certainly do get good accuracy with the standard cadet and bullet, but I think the heel bullet isn't something I'd choose to go back to, when you are so close to not needing one. Relieving the neck slightly is one possibility, but you would have to buy a neck reamer, and probably specially made. Another possibility would be to ream or turn your case necks thinner. But before any of that I would try a bullet of anything between .316 and .319, to see if it expands to seal the grooves. There is a good chance that it will, if it is reasonably soft. Of course you don't want to pay for a special mould only for an experiment. I would lathe turn the test bullets from sticks of lead cast in a steel tube. Or you could expand smaller bullets larger with two punches (the nose can be flat for this purpose) in a hole drilled with an O sized (i.e. .316in.) drill in a piece of metal.

[stubbicatt]

Thanks fellas. I think the heeled bullet is the way I will go with this one.

After looking at the fired cases, they appear to be a nearly straight taper, no shoulder left in them. I sort of figured the majority of the chamber may have been that 310 Greener chamber. I wonder if the chamber reamer the Aussies used to convert them to 32-20 might not have only opened the rim seat and base of the cartridge, but left the rest intact?

The bore on this rifle is just perfect. Even shooting 314's yesterday I was ringing the 200 yard plate at the range. A really neat rifle for sure.

Only shot 10 shots, and there were some small blobules of lead in the first 6 inches of the bore, but they brushed right out.

At first I was happy to buy the rifle. Then I felt betrayed that it wasn't standard 32-20 dimensions. Now I am happy again. I feel like Snoopy doing a happy dance!

Ballistics in Scotland, that 32-20 brass is pretty darn thin as it is. I would be reluctant to neck turn any of the brass for fear of a neck separation, which is a really unhappy experience. Nonetheless, I appreciate the ideas. If the heeled bullet doesn't work out, I guess plan "B" would address reaming the chamber neck a little bit, and returning to a .321" bullet sort of setup.

[stubbicatt]

I have the heeled boolits for the Cadet. My guns are in the original 310. If you would like to try some let me know. How close to Denver are you?
swamp

Swamp, we spoke on the phone awhile ago about 45-70's. I went ahead on and bought the RCBS mould. It should be here by Wednesday. Thank you for your generous offer. --Got any good sources for lead?

[Der Gebirgsjager]

I told this tale once before on another thread. I once owned one of the Martini Cadets that had been converted to .32-20. I purchased a box of .32-20 WCF mfg. by Remington and went through most of the box of 50 without hitting anything at all. The first half of the box left me so puzzled that I fired the remaining rounds at a smooth dirt embankment about 50 yards distant and learned that no two rounds hit in the same location. I was about age 15 at the time and not well funded, so I set it aside. I didn't want to get rid of it because it was almost new in appearance. Years passed and one day I happened to read a letter in the American Rifleman by a fellow that had the same problem, but he had figured out that the .32-20 bullet is closer to .30 cal. and the .310 Cadet was closer to .32. So he started loading with .32 S&W wadcutters and experienced fantastic accuracy. I dug the rifle out, bought a box of .32 wadcutters and tried it out. I found that once the powder was added to the case one could start the bullet with their fingers, then turn it upside down and press the bullet against a table top to push it into the case and seat it flush. No dies needed. It worked just like the fellow said, and the Cadet became very accurate. So much so, in fact, that it became boring. Desiring more flash and bang I sold it for well over $400 back in the 1990s, one of my many mistakes in life. Anyway, you might give it a try.

[swamp]

I don't have any reliable steady sources. Always looking. I have gone to shooting ww or 20-1 in mine. I could trade you a bit if you need.
swamp

[square butte]

Saw one at a guns shop a couple of hours from home last week - Chambered in 32 Winchester special. Could hardly believe my eyes. Had to ask the owner if I was reading the chamber marking correctly. He confirmed that it was indeed chambered in in 32 WS.

[Ballistics in Scotland]

The .32 Winchester Special was a moderately popular rechambering for them, but not, I think, as good as that slightly unusual .32-20. Some people will tell you the 3/4in. diameter barrel threads can swell, producing hard extraction. But some have used it with no such problems, and I think it is only likely with gross overloads or a case based on the .44 Magnum. It will, however, recoil excessively for a rifle of the Cadet's weight and stock design.

[pietro]

.

Converting .310 Cadet to .32 Winchester involves also deepening the loading groove in the top of the breechblock to accommodate the much longer cartridge - AND, being so lightweight a rifle, results in felt recoil that's like getting kicked in the chops by a mule.


.

[Hooker53]

The RCBS heeled Boolits are the way to go on this gun. On mine anyway. I had to trim my case length down a few thousands at a time setting a boolet after every trim until it would chamber. After that, I knew what my case length would be. Between four or five grains of Unique and it shoots like a dream. IV also had good luck with a case full of Trail Boss as well. Swamp and a lot of the other Cadet owners were VERY helpful after I bought mine.

There is also another member on here that cast some good Reg .32 cal hollow base Boolits that are looking real promising. Good luck with your loads. It looks like you are on the right track. These little rifles ate a lot of fun.

Roy
Hooker53

[rmark]

I use 32-20 brass trimmed down to 1.15 inches, with the RCBS heeled bullet and 4.0 grains Universal powder. In essence it's a 310 cadet long. Accuracy so far is 2" at 25 yards, but I'm still working on that. Maybe a bit more powder or softer lead.

I suspect the 32-20 reamer used to rechamber the barrel produced something like a long throated 310 cadet chamber. Brass trimmed to 1.0 inches resulted in 8" groups with keyholes, trimmed 1.2 inches had to be pushed into the chamber.

I tried the .32 wad cutter in untrimmed 32-20 brass with 4.0 Universal, had about 3" groups at 25 yards with occasional flyers.

[Hooker53]

rmark. It would seem that a lot of these little cadets had Dif depth chambers to a small degree. Especially when someone hand fed a 32-20 reamer down in it. After this is done, Bad A-- Wallace calls it a 310 Greener Mag. That's what I tell everyone around here it is. Ha.

[stubbicatt]

Oddly enough, the little girl shot really well yesterday at 100 yards using 314 bulleted ammo. Ordered up the RCBS mould. I guess it should arrive sometime this week. We'll work on building some loads with that bullet.

Thanks everybody.

Regards,
Stubb

[Black Beard]

I normally shoot my 310 with 120 grain RCBS heeled bullets. 4 grains of trail boss in a 310 case. It is very good.

I’ve tried paper patching a backwards bullet which worked fine but the Lee 314-155-2Rs were too long for the rate of spin given theloads I was playing with. The remaining case capacity (0.6cc) doesn’t hold enough powder to make much velocity. 32-20 might work better as you could get them coming out at 1200fps+so more stable. Or if you have a 32 mould for a shorter bullet it would be better as long as it has a step down to a nose section.

I tried a custom 8mm gas check on the front of a 32 wadcutter which worked to seal the front of the bullet. Accuracy was not as good as the RCBS bullet but it showed potential.

Have a look at the 32-20 chamber dimensions:
http://www.saami.org/pubresources/cc...Winchester.pdf
The neck tapers by 4 thou but .319 bullet + 0.012?? cartridge walls is too big for the neck, even if you cut them down.

BB

[stubbicatt]

Yes. Except the chamber on this rifle really closely resembles the 310 chamber. No vestige of a shoulder at all, just a taper from the case head to the case mouth. Best of all worlds. I am not sure yet whether I'll need to trim the cases back to allow chambering, but I'll find out once I make up a dummy round.

The RCBS heeled bullet mould arrived last night. I can't wait to get casting. What a magnificent rifle.

[Black Beard]

Sounds like a very versatile rifle. How much do they go for in the states? Going price for a reasonable one here is £650 ($1000) as an antique.

[stubbicatt]

Black Beard, that's about what we paid for it. But it is mint. Really a beautiful rifle. Bright sharp bore, clean wood, a magnificent rear sight. I'm impressed! BSA made good rifles as well as good motorcycles!