45/70/500

[gizmo]

hey guys, I have an original 1873 trapdoor that I want to start loading black powder cartridges for. I've shot it with the modern smokeless loads designed for these rifles but I don't like to and would like to load up some original type loads the military used. I understand it takes a 45 cal .458 lead 500 grain bullet over 70 grains of powder. Has anyone loaded these before. What type of powder Fg, ffg, or fffg? What primer do you use, and is some type of spacer needed to load the round? If so what is the spacer made of and how thick? I don't want any crazy loads just something safe and original. Thanks

 

[JimP]

Loading black powder cartridges is a lot of fun even if it does get dirty after you pull the trigger.

The original load was 70 grains of FG black powder with a 405 grain bullet at around 1200fps. I would just use a Federal GM210, Win LR, or their equivalent. But for a starting load I would drop the grains down to 50 or so grains to start with. For a filler I just use cornmeal on the top of the powder.

If you can't find FG powder then go to FFG and rework up the load.

50 grains of FG powder should give you around 1000fps with the 405 grain bullet
60 grains of FG powder should give you around 1200fps and 70 should up the velosity to 1300fps

For the 500 grain bullet

50 grains=900fps
60 grains=1050
70 grains=1150

This is from my load data.

Also for the max loads you may need to improvise a drop tube for the powder and compress it with heaver bullets. You also need to know that black powder is measured and not weighed so you would need a black powder measure to get the correct loads. They can be picked up at just about any store that is going to sell black powder firearms. Sorry but I do not have the conversion but there are some out there on the net but the vary widely.

There is also some load data on the Goex Black Powder site.

 

[gizmo]

Thanks for the info, I was most interested in the 500 grain bullet as that was the original military load. Not that that really makes a difference either way. Will cci lr primers work, I have a bp powder measurer as I shoot a little bp guns on occasion. With the cornmeal does a wad or anything need to separate it from the powder and how much do you use? I also assume no crimp as its a single shot? Thanks for the info.

 

[IronCowboy]

Yup, the original load was .45-70-405, 45cal bullet, 70grns BP, 405grn pill. I'd work up gingerly in an old trapdoor if I wanted to get 70grns under a 500grn pill.

 

[JimP]

On the cornmeal, just place it on top of the black powder and the bullet will hold it in place and any large rifle primer will work.

You can experiment with a crimp but it isn't needed with your single shot.

 

[gizmo]

I found this and thought it may interest yall. http://www.gunnersden.com/index.htm.45-70-black-powder.html I found it quite an interesting article.

 

[AZDAVE]

Gizmo,
Have played with trapdoors for a while, you are embarking and a fun project. Here is a link to a book that
has more quality info on loading for original trapdoors that all the other reference data I found anywhere.

http://www.4570products.info/Loading-Cartridges-for-Original-45-70-Springfield-1.htm

Have fun and shoot straight

Dave

 

[gizmo]

Thanks Dave I will definitely check it out. I hope to get some adequate loads worked up so I can shoot a deer with the rifle this year. Thanks again.

 

[Bob Nelson 35Whelen]

Loading black powder cartridges is a lot of fun even if it does get dirty after you pull the trigger.

The original load was 70 grains of FG black powder with a 405 grain bullet at around 1200fps. I would just use a Federal GM210, Win LR, or their equivalent. But for a starting load I would drop the grains down to 50 or so grains to start with. For a filler I just use cornmeal on the top of the powder.

If you can't find FG powder then go to FFG and rework up the load.

50 grains of FG powder should give you around 1000fps with the 405 grain bullet
60 grains of FG powder should give you around 1200fps and 70 should up the velosity to 1300fps

For the 500 grain bullet

50 grains=900fps
60 grains=1050
70 grains=1150

This is from my load data.

Also for the max loads you may need to improvise a drop tube for the powder and compress it with heaver bullets. You also need to know that black powder is measured and not weighed so you would need a black powder measure to get the correct loads. They can be picked up at just about any store that is going to sell black powder firearms. Sorry but I do not have the conversion but there are some out there on the net but the vary widely.

There is also some load data on the Goex Black Powder site.

@JimP
The original 45/70 cases were a balloon type case that allows the full 70 grains of BP to fit the case.
Modern cases are stronger and don't have the balloon head so it may be difficult to get the whole 70 grains in the case and still seat a 500 grain bullet.
Bob

 

[Bob Nelson 35Whelen]

On the cornmeal, just place it on top of the black powder and the bullet will hold it in place and any large rifle primer will work.

You can experiment with a crimp but it isn't needed with your single shot.

@JimP
I would have thought greased card wads would have been better to reduce fouling . Corn meal has been and save on have been known to cause barrel ringing in some cases with reduced loads of smokeless powder even in the stronger MARLIN action
Bib

 

[bruce moulds]

part of the success of the 45/70 as a military rifle was the govt bullet in both 405 and 500 gn wt.
good ones can be had from buffalo arms.
lyman are better avoided.
black powder lube is required, as some smokeless lubes make a tarry type of fouling.
the way to establish a starting load is to work out how much powder you need to droptube into the case, so that with a wad on top and the bullet on the wad, the coal is what you want.
shoot some groups with this load.
next increase the load by say 1 gn, and compress the powder so coal is the same as the first load.
keep doing this 1 gn at a time until you go past where the rifle groups best.
forget the old myth about loading by volume, and weigh the charges.
do not compress with a bullet, as this can enlarge the diameter of cast bullets.
a compression die is best.
you will possibly find that the optimum charge wt is not 70 gns, for the reason bob gave, and also powder density varies from batch to batch.
a 30" droptube is ideally used to get more powder in, and also get it in in such a way that ignition is more consistent.
either low density polyethylene or gasket material makes good wads in 0.030 or 0.060 thickness.
from memory, the carbine load with the 405 gn bullet used something like 55 gns powder.
1f, 1.5f, and 2f will all work in 45/70.
when testing loads blowtubing will keep the powder fouling soft, an aid to accuracy, as will wiping between shots.
shooting many shots dirty will end eventually in not beig able to chamber a round due to fouling, particularly in hot dry climates.
a good lube can be made from beeswax, tallow, neatsfoot oil, and a bit of lanolin.
these are all natural products which work well with black powder.
should you need to raise the melting point a bit due to hot weather, replacing 1/2 of the beeswax with ozokerite will help.
bruce.