Loading 45-70 450gr for Trapdoor - Help

[bowiemaker]

I have a nice original 1884 trapdoor rifle and I want to load BP ammo for it. I cast a bunch of bullets using the Lee 457-450-F double cavity mold. According to the literature that came with my reloading dies, the maximum overall length of the cartridge is 2.550". I measured some 405 gr cartridges from Buffalo Arms and they were 2.51". That included 2.10" for the case and 0.41" of lead extending beyond the case.

My problem is that the 450 gr bullets are 1.08" long. If I seat them to what I thought was the crimp line .50" from the base, the overall cartridge length would be 2.70". To get to the 2.50" length, I would have to seat the bullet 0.72" deep. That seems like a LOT of compression if I am loading anywhere close to 70 gr of  Goex 2f. I am not even sure I can compress it that much. (I do have a compression die on the way.)

Any advice or recommendations?

[Blackpowder Burn]

Bowiemaker,

First, try making up a dummy round and see if it will chamber.  Single shot rifles are not limited to the same OAL as lever guns, etc.  OAL is often dictated by the maximum length the action will handle, not what will chamber.  If it won't chamber, then try loading about 55 grains of BP.  You should be able to compress that and it is the standard Trapdoor carbine load when combined with a 405 grain bullet.

[Ranch 13]

From your picture it looks like you're trying to seat the bullet to deep. The first band should be exposed at the case mouth. The real question is will the nose of the bullet fit in the bore of the rifle.
You can easily compess 70 grs of 2f black in a 45-70 case with a compression die.

[Bruce W Sims]

@ Ranch:

Given what you just shared, how "forgiving" would the result be to shoot the round as is.

Just wondered....

Best Wishes,

Bruce

[Ranch 13]

If the case isn't bulged and it will chamber, there wouldn't be much wrong with shooting it as is. Accruacy might not be great , and there could be some leading.. but nothing catastrophic would happen.

[bowiemaker]

Does anyone know if the original 500 gr bullets for the trapdoor were seated that deep or if the cartridge was longer than 2.51" ?

I purchased and read JS Wolfs excellent book on the trapdoor but could not find that information. He stated that powder was compressed up to .65" but I would have to compress more than that if I were to maintain a 2.5" overall length. He also states that flash holes have to be enlarged and magnum primers used to get good ignition of highly compressed powder.

I have not loaded any rounds yet as I am trying to figure out the proper procedure first. I think I will load a dummy round at the 2.7" length just to see if it will chamber.

[Ranch 13]

The 2.55 length is mostly intended for the round to cycle thru the 86 Winchester, and not necessarily for a single shot.
As long as the round will chamber in your trapdoor you're good to go.

[Cliff Fendley]

The 500 grain like the Lyman 457125 has a smaller diameter nose than the driving bands. It will chamber in the trapdoor or other single shot just wont work in a lever action.

I believe the lee mold you have is the same way.

[bowiemaker]

I made a dummy round to test the chambering. At 2.7" it would not chamber. At 2.6" it was forcing the nose into the rifling. It does have to be 2.54" to chamber without forcing the trapdoor closed. So I have learned that I will need to seat the bullet pretty deep into the case. Now when my compression die arrives I will have to figure out how much powder I can use in the available space. I thought maybe someone had already been down this road with the 450 gr bullets and could recommend a load.

[Ranch 13]

What is the diameter of the nose on that bullet?
Have you tried dropping one in the muzzle end to see if the nose will go to the grease grooves.
Haven't ever loaded a 450 gr bullet in the 45-70 , but sure have shot a long ton of 480 and 535 grs, all loaded over 70 grs of 2f.

[bowiemaker]

These are .457 and they do drop into the muzzle up to lube grooves.

[Bruce W Sims]

If the case isn't bulged and it will chamber, there wouldn't be much wrong with shooting it as is. Accruacy might not be great , and there could be some leading.. but nothing catastrophic would happen.

R...thanks../B.

[bowiemaker]

My goal is to work up an accurate and consistent load. Our NCOWS group is planning some 250 yard buffalo gun shoots. My Springfield is a model 1884 infantry rifle with a 32 1/2" barrel made in 1887. As I understand it, the carbines usually shot the 405 gr bullets and the rifles usually shot the 500 gr. although 405 gr were also used in the rifles. It looks like I will have do some testing to find a good 450 gr load.

[Ranch 13]

If you use the 405 gr government bullet, with 70 gs of 2f black, it is amazing at how well those buffington sights are regulated.

[frimath]

I could be really really wrong, but I seem to recall the Army using 305 grain bullets for carbine/ cavalry !! I have a copy of a book by a fellow named Wolfe and it deals with loading specifically for the US issue Trapdoor. It's a terrific book and if you are going to reload holy black for the trapdoor you simply must (!) get that book!  The carbine rounds were down loaded from the 70 grains to , I think, 55 grains. I seem to recall that Sgt John Ryan had traded some Army issue rifle rounds for carbine rounds for use in his Sharps rifle, which he used to good effect as a counter sniper weapon against Souix/ Cheyanne sharpshooters at the Little Big Horn. But I digress,, one of the things Wolfe recommended in his excellent book was to enlarge the flash hole in the brass casing. I've tried this along with a couple of his other recommendations and I was pretty pleased with the results. Additionally, you " simply must" slug that bore.  Over the years I have seen several different rifle in particular that had greatly varied bore dia. Softer lead is another route you may want/ have to explore if you have an oversized bore.  Loading holy black is a little bit of voodoo and a little bit of luck and sometimes a good deal of experimentation , especially in regard to these trapdoors. I wish you hours of fun in this endeavor.  But...........get that book!!  Hope this helps a little bit.  Johnny F

[frimath]

BTW you " simply must" use a compression die and figure on compressing a good half inch or whatever it takes to push whatever size bullet you are going to use , 405-450-500-525 grain, to cover all of those grease grooves.  See Wolfe! Regards Johnny F

[bowiemaker]

I did purchase and read Wolfs book. He deals mostly with the 405 gr hollow based bullets and seemed to have the best accuracy with them. He does not cover a 450 gr load as he was striving to duplicate the original military rounds and accuracy.

I do not have the means to slug and accurately measure 3-groove bore.  I did drive a .452 bullet from the muzzle and it was snug. The .457 bullets that I am loading took some effort to drive through the barrel.

I am going to load some with standard flash hole and primers and some with enlarged flash holes and magnum primers for comparison when my compression die arrives. That, along with trying various amounts and compressions of BP should give me something to work with.

The 450 gr may have been a mistake but since I will be shooting 250-300 yards I thought that would be a good compromise between the 405 and 500 gr. If I can't get good results with the 450 I will probably buy the 405HB mold but since I have about 300 of the 450s already cast I'll see how they perform.

[Ranch 13]

Don't waste your time or wreck any cases with that flashole drilling stuff. That was a misquided effort by Wolf to replicate the affect of the old Berdan primers, but the big thing he overlooked was that those primers were actually weaker than todays primers, so by compounding the larger flash holes with the force of the magnum primers he went backwards..
Most of the folks that chase the fine accuracy needed to hit the x rings out to 1000 yds and beyond go with large pistol primers, or thin paper wads between the primer and the powder charge.
Remington 9 1/2 , and CCI br2 primers work quite well for me, and have had some good results with CCI and Winchester large rifle and large pistol primers.

[Bruce W Sims]

For the most part I am following much of what is being shared here. It DOES beg a question, however.
I am left wondering what standard of performance is reasonably expected from this trapdoor piece
before a person starts working to wring every last quirk from the mix. The reason I ask is that
I tend to look for "typical" performance in a piece to appreciate what the Average Joe could reasonably expect.
I don't know that everyone wants to have an "Adobe Wells" event each time they shoot...but maybe they do. In
the meantime I am left to wonder what a "standard performance" might be.  Anyone?

Best Wishes,

Bruce

[Ranch 13]

Standard performance would be something along the lines of 2-4 minutes of angle groups at what ever distance the person chooses to shoot.