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Discussion Starter · #1 ·
If I use trapdoor data for a 385gr. lead bullet for a 350gr bullet. How much will it vary in fps? Is there a way to guess? I don't have a crono yet.
 

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Big Mike, since you gave the big out, I will guess, based on shooting just those weights across a chrono this week.
the 350 g was right at 45 to 70 fps slower with the same powder charges. before people start chewing strips off me, the extra weight raised the pressure and gave faster velocities, IN MY GUN.
 

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Discussion Starter · #4 ·
As close as I can calculate. This is pretty hypothetical, is that bullet and data I could get 1575 fps and around 1900 foot pounds.Now whether my guide gun likes that is another question. I'm trying to work up loads with the components I have for Whitetail.
 

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45 caliber 70 grains of black powder, and a 405gr RNPB boolit

why mess around with anything else
That combination was made in heaven and will summarily kill anything in the Western Hemisphere.
 
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can't add to the last two posts. just practice good hygiene with the BP. and that means good cleaning.
 

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45 caliber 70 grains of black powder, and a 405gr RNPB boolit

why mess around with anything else

Can you really get 70grs of black in a modern .45-70 case & still seat the bullet to feed through a Marlin? I can't get 40grs of black in a modern .45 Colt case?
I agree though the old 405gr BP load was & is powerful enough to kill anything on this contenent. This load has proven it'll completely penetrate a Bull Bison & they are big animals.
The difference between killing & stopping is considerable though, & here I'd want more velocity.

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Big Mike
Having not chronographed any 385 or 350gr bullets, but a LOT of 405gr bullets I'd just guess the velocity difference won't be great. I think it'll only be about 40fps difference. If the 385gr bullet is lead & the 350gr is a jacketed, the difference may be none as the jacket will probably give more resistance to the bbl. than the lead bullet?
 

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Discussion Starter · #9 ·
Thanks Frank, the 350 is lead.I shot some of my first 405gr jsp this weekend. Even at 52gr of powder it beat the heck out of me.Thought I'd try some lead bullets and see what I get.
 

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I back my plain bases with a veggie wad, so I use 68gr of 3f by volume, not weight. (By weight Its less)
Im also known to add 2gr green dot at the primer, for a tad more FPS, but Id not do that in a trap door, only my 1895s.
do as i say, not as I DOH
 

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Discussion Starter · #11 ·
I think I led everybody astray. My fault, I'll blame it on inexperience. I'm shooting a 1895 GS looking at trapdoor velocities with modern powder.
 

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Big Mike do you have a Lyman Reloading Handbook 49th edition? It's a great manual & has all 3 levels of .45-70 data.
I often load Trapdoor loads to enjoy, I have worked up 3 loads I really like one is a heavy hunting load, accurate, but not really pleasant. I also have two lighter loads that ARE fun one is only 1088fps with a 405gr lead bullet, & the other is just over 1400 with my JSP hunting bullet. The later two loads are fun. These 3 loads will do anything I want done with the .45-70.

You don't have to run them at max to have a good load. A heavy load is nice for the bigger stuff, but paper & small game really don't require a 405gr JSP @ 1720fps. I think you can find a very nice load in the trapdoor range that'll still be fun to shoot & effective on game the size of deer too. You will probably end up with more than one load if your are shooting for fun as well as hunting.
Good shooting.

Do you have a Past recoil pad? They aren't all that expensive & really help muffle recoil, they slip on & give about 3/8" padding. I like them a lot.
Good shooting.
 

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Discussion Starter · #13 ·
Thanks Frank. Yeah the Lyman 49 is what I'm looking at. I'm looking at the 385gr data for my 350 Dardas. I found other data where I can take my jacketed bullets down few grains. I'd love to get one of these bullets to around 1400fps or so. I still want to keep the energy level acceptable.
 

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big Mike, I'd recommend that you try Trail Boss to get what you are looking for. easy to load with and easy on the shoulder. just puts fun back in an extended day of shooting a 45-70.

I just went and loaded some 350's with trail boss here are the results
14 grains TB 80% load max being 17.5
velocity 960 fps
accuracy 3shot @ 50 yards ,75 inch
feels like cowboy loads out of a 92 win. I will bump up the loads some and see if I can get 1400fps.
if my math is right I think 1170 is about top fps to be expected with trail boss loaded per manufactures directions.
I have talked with guys that use compressed loads of TB but why bother when you can go to other powders to achieve faster fps.
 

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Discussion Starter · #15 ·
Powder is a shot in the dark as to what becomes available. I've been shooting some with 13 grains of Unique and that's a pretty sweet load too.
 

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I have never used Unique in rifle loads, going to give it a try. I lucked on trail boss cheap and bought a bunch. just fun to shoot no matter what the round.
I need to buy some more 350's though. the rounds I loaded tonight finished them. Midsouth has some in stock so guess I will make an order tomorrow. they shoot so fine out of both my 45-70's
 

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Discussion Starter · #18 ·
Question for you. I'm looking at these trapdoor level loads. I shouldn't be concerned about max loads in an 1895 with a cup of 24000? I know max is always s concern. But shouldn't be an issue should it.
 

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Thanks Frank. Yeah the Lyman 49 is what I'm looking at. I'm looking at the 385gr data for my 350 Dardas. I found other data where I can take my jacketed bullets down few grains. I'd love to get one of these bullets to around 1400fps or so. I still want to keep the energy level acceptable.


I'm pretty sure you can reach 1400fps & still stay in the "trapdoor" level using IMR4198, H4198, Varget, IMR3031, & probably others.
I use H4198 & Varget for just over 1400fps & the Rem. 405gr JSP, these loads are pretty pleasant.
 
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