Trapdoor 45-70 powder


old scout
September 23, 2011, 09:27 AM
I aquired an H&R 45-70 carbine and am considering reloading this round. I purchased 100 rounds of LOAD-X 45-70 to have some brass to start with. Ammo was priced rite I beleive @ $20 for 20 rounds loaded 305 gr bullets. I have a Dillon 450 which I'll be using. What brand if dies would be recomended as well as powder. I see Trail Boss is talked about frequently, but I also see that it is BIG $$$. Looks like 9oz will only supply about 22 rounds. Any alternate powder that would be less expensive out there. Lead 305gr bullets look to be about 20 cents each. At the Load-X pricing, I'm wondering if I can reload for any less that their price.

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September 23, 2011, 10:00 AM
I think your math might be a little off, there, in the number of loads you get out of a 9 ounce can of Trail Boss powder. For a 305 grain lead bullet, the recommended .45-70 load of Trail Boss is about 14.0 grains. 9 ounces of powder is about 3900 grains, divided by 14 gives about 278 rounds per cannister, not 22.

September 23, 2011, 10:15 AM
As far as powder...Accurate 5744 is something I've had success with. I linked to load data in this post (

September 23, 2011, 10:55 AM
IMR-4198 is a real good Trapdoor powder with 405 grain lead bullets.
Might be something better for other types or weights, but you didn't say what bullet you might want to use.

It will give you 200 - 222 rounds per pound.


September 23, 2011, 11:08 AM
I've already loaded about 50 rounds out of my can and it still looks nearly full. Thats at 15 grains a round.

highlander 5
September 23, 2011, 11:14 AM
I second 5744,good powder for a lot of the old black powder cartridges.

September 23, 2011, 11:49 AM
AA5744 is bulky, shoots well through the Shilen barreled Martini Henry, have not shot enough through the BPCR, I am getting slight leading at the end of the barrel, might be a lube problem. The BPCR barrel is about 4" longer, might be running out of lube.

These loads are appropriate for black powder guns, the Martini Henry rifle has a blackpowder receiver.

45/70 Martini Henry 26" Shilen Barrel

405 LRN 26.5gr AA5744 R-P cases WLR
29-Apr-04 T = 80 F

Ave Vel = 1294
Std Dev = 14
ES = 40
Low = 1274
High = 1314
N = 15
Group Size Very . good

405 LRN 27.0gr AA5744 R-P cases WLR
24-Mar-04 T = 70 F

Ave Vel = 1284
Std Dev = 23
ES = 80
Low = 1263
High = 1343
N = 12

405 LRN 27.5gr AA5744 R-P cases WLR
15-Apr-05 T = 75 F

Ave Vel = 1363
Std Dev = 25
ES = 97
Low = 1298
High = 1395
N = 20

Group Size good offhand at 100 yards

Winchester BPCR M1885 30" Badger barrel

Ladder Sights: 5 graduations per 1/4 inch major.
1/4 inch major is 25 MOA, 1 grad is 5 MOA, 1 Veriner is 1 MOA

405 LRN 27.5gr AA5744 R-P cases WLR trimmed 2.085"

29 May 2010 T = 89 F

Ave Vel = 1324
Std Dev = 9
ES = 26
High = 1338
Low = 1312
N = 6

September 23, 2011, 01:24 PM
67 grains of Swiss fffg. Great fun.

September 23, 2011, 02:04 PM
20 grains of 2400 over a 378 grain gas checked round nose bullet

September 24, 2011, 01:31 AM
I have mostly used 4198 for my 45-70 ammo but recently tried AA-5744. I hear it's a good powder for making ammo that was originally made with black Powder and they are correct. I think it's just a little more accurate than the ammo I make with 4198.

September 24, 2011, 07:35 AM
I bought the big canister of Trail Boss, actually 3 of them. I like the propellant in all my CAS loads and use it for almost all the low pressure lead ammo I reload. I have never tried AA5744 but a LOT of friends have used it with great success so I will get a can next time I order some supplies. I like the idea of a bulky load that has little chance of allowing the propellant to move around in the case and no need to add a filler. The TB does this for me and I found that I may be an old dog but learned at least one new trick. Wish they had it around years ago.:D

old scout
September 24, 2011, 08:38 AM
I need to get away from the metric system, I was thinking "GRAMS" not GRAINS for my calculations on the powder. Thanks for the education and info.

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