40-60 Maynard 1873-thick rim

[dig-um]

Just acquired model 16 Maynard-chamber 2.25 deep-slugged .418
could be 40-70, will need to cast the chamber
perfect bore so will need thick rimmed brass to shoot-any source?
Would also like some vintage rounds of the 40-60 and 40-70 Maynard
thx

[Bent Ramrod]

Try Dixie Gun Works and S&S Firearms. Also Bob Hayley in Texas.

And congratulations! The 16 is about the coolest Maynard there is.

[elk hunter]

Welcome!

You may want to look at Wards Auctions for Maynard ammunition, probably won't be cheap but some should turn up there at some point.

https://www.wardscollectibles.com/

[Reverend Al]

You'd have to check the chamber dimensions of your rifle, but years ago a friend of mine had a Maynard thick rim in .40 calibre and he made shooter brass from .30-40 Krag cases by soft soldering a suitable thickness of washer onto the inside of the rim of the Krag cases. They worked just fine for him with the black powder loads he was shooting in it ...

[dig-um]

Chamber cast was 2.35 and if the rim-per cartridges of the world is .065 then we have a 40-70 Maynard. The same ref says 30-40 will work but short. Bore cam showed minimal micro pitting. Can't wait to find some washers or brass. May collectors show coming up here in Denver!!

[LynC2]

If you can't find brass, perhaps the Hornady .405 Winchester brass may be workable.

[dig-um]

Rocky Mountain Cartridge Co turns from solid brass all types and will do 20 for $70-anyone used them-looks like they do about any case--
thx

[Bent Ramrod]

Haven’t bought Maynard cartridges from them, but my .22-15-60 SS brass is all from RMC.

The fit and function could not be improved upon.

The only downside is that, not being drawn, they do not last long when run through sizing and expanding dies. Once I found that out, I stopped resizing and expanding and just deprimed and reloaded the fired cases, seating the boolits by hand. They’ve worked fine ever since, with no cracked mouths.

That reloading regimen is doubtless what you will be doing as well, so the cases should work fine for you.

If you have any ideas about reduced case capacity for smaller powder charges, thicker case mouths for special boolits, odd lengths for your particular chamber, talk to them before ordering. They can make the shells to a standard pattern or customized, whatever you want.

[Deadeye Bly]

Are you sure it is an 1873 rifle. The 1873 rifles used a thick head case with a rim thickness of .135". The 1882 rifles uses a rim thickness of .070". The 40/70 cartridge is a 2.4" long cartridge so your chamber depth seems off. The Krag brass is short for the 40/70. The Hornady 405 brass can be made to work but may need to be reduced in diameter a few thousandths right in front of the rim. I have brass headspace rings made to convert the 405 brass into the 1873 brass. They press in place and are considered permanent once installed. Make sure what you have. I may be able to help you out.

[Reverend Al]

Are you sure it is an 1873 rifle. The 1873 rifles used a thick head case with a rim thickness of .135". The 1882 rifles uses a rim thickness of .070". The 40/70 cartridge is a 2.4" long cartridge so your chamber depth seems off. The Krag brass is short for the 40/70. The Hornady 405 brass can be made to work but may need to be reduced in diameter a few thousandths right in front of the rim. I have brass headspace rings made to convert the 405 brass into the 1873 brass. They press in place and are considered permanent once installed. Make sure what you have. I may be able to help you out.

Deadeye Bly ... I sent you a PM regarding these headspace rings for my new (to me) Maynard ...

[Reverend Al]

Does anyone know how to reach "Deadeye Bly"? I've sent him a PM through this site and a PM through the ASSRA site and haven't had a reply to either one of them yet. I'd really like to contact him about getting some of his brass headspace rings to make some "shooter" cases for my thick rim Maynard 1873 in .40-70 Maynard.

[Reverend Al]

OK, I took some measurements today and it looks like my rifle is a .40-60 Maynard 1873 rather than a .40-70. Using the probe on my calipers the chamber measures about 2.163" from the back of the barrel to the front of the chamber where I can feel a definite ridge or shoulder at the end of the chamber, so with the 1873 .135 thick rim (less about .064" for the thickness of the .303 British rims on the donor cases I'll use) the total case length comes out at about 2.234". The .40-60 Maynard has a nominal length of 2.200" so allowing for a bit of error on my part (or a somewhat long chamber or a slightly eroded throat?) it looks like it is chambered for .40-60 rather than the .2.400" long .40-70. I do still need to slug the barrel and see what the bore and groove dimensions are on this particular rifle and I'll check to see what the twist is too. I already have RCBS moulds in .410" for 300, 350, and 400 grain bullets and should be able to make something work with a bit of testing.
I measured some .303 British cases that I had previously fire-formed and blown out straight in my Ishapore Lee Enfield No. 1 MK III in .410 Musket and they measure out at about 2.165" to 2.185" before squaring up the case mouths so it looks like I'll be able to use some of my thousands of rounds of "on hand" .303 Brit brass rather than having to source some longer .30-40 Krag cases, so that's a bonus!
Now if I could only reach "Deadeye Bly" and arrange to get some of his brass adaptor washers to make the proper fitting thick rim cases to bridge the gap between the barrel and the breech face on this 1873 Maynard I'd be in business and I could go shooting!

[John Boy]

40-60 ... https://www.rccbrass.com/?s=40-60&post_type=product
40-70 ... https://www.rccbrass.com/?s=40-70&post_type=product

[Reverend Al]

I think that for $6.60 US EACH I'll keep making my "shooter" brass out of reformed .303 British or .30-40 Krag cases and use a brass spacer washer or some of Deadeye Bly's adaptors ...

[Deadeye Bly]

Reverend Al, I responded to you on the ASSRA forum before I read this. I've been away for a while shooting and vacationing and I do not post on public forums when I'm away form home. Yes, it appears you have a 40/60 which is much rarer than the 40/70. The 303 brass will be too short for the 40/60 but Krag brass will work and possibly .405 brass. The bullet diameter in an 1873 will probably be .423"-.424" diameter but possibly .416" but more likely the larger diameter.

[Reverend Al]

Yes, I got your PM at the ASSRA site and I've responded to it with a couple more questions. I still have to slug this .40-60 Maynard to get the actual barrel dimensions, but the previous owner was using a .400" RCBS 300 grain bullet (sized down from it's original .410" as cast diameter) and then paper-patching them back up to .410", so it sounds like he was patching to bore size rather than groove size. The slightly short length of the .303 British cases isn't a problem for me since I have a Kal Max case stretcher and can lengthen some .303 cases to whatever length is needed to get the correct finished overall case length for the .40-60's. (That and I already have thousands of rounds of .303 British brass on hand and .30-40 Krag and .405 Winchester brass is a little bit scarce up here in Canada and also a bit pricey.)