Jacketed 8mm bullets in 32-40 rifle. ??

[Bruce Scott]

Has anyone tried them? Weight / make / results?

Hornady do 8mm (.323 dia) in 125Gr SP , 150Gr SP, 170Gr RN and 195Gr SP

[edsguns]

DO NOT try this! The true caliber if a 32-40 is actually .308-.309. This round is actually a .30 caliber round, which should only be loaded with bullets of .308 diameter. I'm afraid ugly things might occur if you were able to load the .323 bullets in cartridge and chamber and yanked on the trigger. Good luck otherwise!

[Sixgun]

I don't want to sound like a 'know it all" but geeze, I have been at this game for over 35 years and I enjoy passing along what I have learned to other shootists.

The 32-40 is actually .321. It uses the same bullet as the 32 Spl. I suppose 8mm bullets could be used but they will be .002 over, the jackets will be thicker, and the point would have to be ground down for leverguns. I would not do it because most of the guns made for the 32-40 have blackpowder steel and that .002 over diameter could raise pressures to the point where you will eat steel. Buy 32 Spl. bullets.-----------------------------Sixgun

[Don McDowell]

You'ld need to slug the bore, its liable to be closer to .320 than the 323. You might get by with the 321's intended for the 32 special.
Unless that gun is of recent manufacture it'ld most likely be best to go with cast bullets in it.

[TooTech]

You can use bullets intended for the .32/40 in J-bored 8mm Mauser cartridges (.318 bore size).

Work your loads up carefully!

[Bruce Scott]

Thanks for the replies. The idea was prompted by the limited choice in 32-40 bullets. They seem to be pretty much limited to 170Gr FPs.

I will be using a single shot with a new Montana Rifleman barrel.

[Chuck 100 yd]

Bruce, if that rifle is still in the planning stage, why not use an 8mm barrel? I did on my Ruger #1 .32-40 and it is a great shooter with cast bullets from my NEI mold. I size .323 and breech seat for groups well under .500 when I am doing "my part" as they say.

[BenT]

Paco wrote in his article on 32 special that he use 8mm bullets without a problem . But I don't know the vintage of your rifle . So slugging the barrel would be a good place to start.

[RSY]

DO NOT try this! The true caliber if a 32-40 is actually .308-.309. This round is actually a .30 caliber round, which should only be loaded with bullets of .308 diameter. I'm afraid ugly things might occur if you were able to load the .323 bullets in cartridge and chamber and yanked on the trigger. Good luck otherwise!

I think you're thinking of the .32-20.

[LeverBar]

Winchester .32-20's are .312--not .308.

I've read MAYBE the Thompson Center .32-20 bore is .308?????????

[junkbug]

Hey Bruce;

I have learned, through personal experience, that the bore size is not the limiting factor. The size of the chamber/throat area is where the critical point is.

If I had a .32-40, or .32 Winchester Special, I would perchase a custom Lee push through sizing die in .321" I have used these on jacketed bullets, as well as cast, many times. When sizing jacketed bullets, I use clean motor oil as a lubricant.

Lee even recommends using their push thru sizer on jacketed bullets as a way of making usefull bullets for the 8x56mm Steyr/Hungarian military cartridge. That is where I learned all about throat size and bullet diameter. These rifles and carbines have thoats so large, I even found I could chamber and safely fire un sized .338" bullets in bores that nominally ran .329", but usually measured .330" to .332". I had two sizers, Lee's facttory .329", and a custom made .333" push thru sizer.

If you already have a rifle, see if a 8mm bullet will slip fit into a fired case. If so, that would be a good first indication that it would work. Even if it doesent, load an 8mm into a fired case as a dummy round. If it will drop into the chamber, and fall out again of its oun weight, the chamber is large enough for unsized 8mm bullets. If not, you will have to resize the bullets, or thin the case necks.

Good luck.

Sean

[Bruce Scott]

Bruce, if that rifle is still in the planning stage, why not use an 8mm barrel? I did on my Ruger #1 .32-40 and it is a great shooter with cast bullets from my NEI mold. I size .323 and breech seat for groups well under .500 when I am doing "my part" as they say.

I should have thought of that - ! The rifle is all but complete with a .321 barrel.

[Bruce Scott]

Hey Bruce;

I have learned, through personal experience, that the bore size is not the limiting factor. The size of the chamber/throat area is where the critical point is.

If I had a .32-40, or .32 Winchester Special, I would perchase a custom Lee push through sizing die in .321" I have used these on jacketed bullets, as well as cast, many times. When sizing jacketed bullets, I use clean motor oil as a lubricant.

Lee even recommends using their push thru sizer on jacketed bullets as a way of making usefull bullets for the 8x56mm Steyr/Hungarian military cartridge. That is where I learned all about throat size and bullet diameter. These rifles and carbines have thoats so large, I even found I could chamber and safely fire un sized .338" bullets in bores that nominally ran .329", but usually measured .330" to .332". I had two sizers, Lee's facttory .329", and a custom made .333" push thru sizer.

If you already have a rifle, see if a 8mm bullet will slip fit into a fired case. If so, that would be a good first indication that it would work. Even if it doesent, load an 8mm into a fired case as a dummy round. If it will drop into the chamber, and fall out again of its oun weight, the chamber is large enough for unsized 8mm bullets. If not, you will have to resize the bullets, or thin the case necks.

Good luck.

Sean

Thanks Sean,
I will order a .321 custom Lee sizer die. This one should keep me entertained for a while..

[Leverdude]

DO NOT try this! The true caliber if a 32-40 is actually .308-.309. This round is actually a .30 caliber round, which should only be loaded with bullets of .308 diameter. I'm afraid ugly things might occur if you were able to load the .323 bullets in cartridge and chamber and yanked on the trigger. Good luck otherwise!

Who told you this stuff?

A 32/40 is a 32 calibre, .321 usually. I dont think I'd use .323 jacketed bullets but lead should be fine if they shoot well. I'v used both Hornady & Speer .321 jacketed 170 gr bullets. My gun likes them both fine.

[LeverBar]

.323 and .322 lead shoots fine from my .32-40.
.321 for Jackets.

As stated earlier in this thread by RSY, maybe edsguns was thinking of more modern .32-20's???

[Hobie]

Winchester .32-20's are .312--not .308.

I've read MAYBE the Thompson Center .32-20 bore is .308?????????

That is correct. They were too cheap to tool up for a .312" barrel. They were successful in marketing it as a benefit for being able to use more easily available bullets.