Thread: Making .40-40 Maynard 1873 ammunition.

Like that of the parts and disassembly of the 1873 Maynard I found very little online about how to make 1873 style Maynard cartridges. Here's a few pictures that show the process. This process will follow for many of the Maynard variants of the era with the thick rim.

Cast chambers to determine your rifles cartridge. I have two barrels which where identically chambered but different bores and twist.
Ignore "38" vs "40" this rifle was advertised as having a .38 & .40 cal barrel. Both were in fact .40.



Look at reference material and looks like we've got .40-40 Maynard 1873. Here's what and original looks like.


Need to make rims, and looks like .30-40Krag brass will work well. .303 brass would of possibly worked but I may have needed to slim down the case base dimension a very small amount. I elected to avoid this additional work with .30-40Krag as it is fractionally smaller at the base.
I scaled these dimensions off some older photos.









Trim and expand the .30-40Krag brass. I annealed as well before expanding.







Chambering the manufactured cases:


Proof of concept sorted. Time for mass production. Make a form tool for inside and outside profile. I got these down to about a minute per rim. I made 100 all up because anything less than 100 rounds of each cartridge is emergency levels of austerity.
Forgive the cuts in the video, I was operating a lathe one handed and couldn't find the in feed lever with my left hand which was hidden behind my phone. So i've edited out the pauses between actions for brevity.







Time to test fire - which went perfectly. Good gas seal, cases fire formed quite nicely, they'll likely expand a bit more over time as well.
Fired cases.

Fired vs unfired.


Of course to avoid priming these with a hammer (wouldn't be the first time, won't be the last...). I'll need a few shell holders. This I consider is the absolute limit of case size you can fit into a Frankford Armoury hand primer. It is also the lightest shell holder I own. Well, because after making it there's bugger all steel left.






Normal shell holder for depriming in press and other assorted press related activities.