1884 trapdoor

[bigted]

Just wanted to post this in a cautionary warning.

Finished watching a fellow on YouTube shooting the rifle with a smokeless powder load of the upper 50's grain of IMR 3031 behind the Hornady 300 grain jacketed bullet.

Now I am telling this cautionary tale as a warning as I believe that this is way over the top in power for the old trapdoor design.

Now I think we could probably get by with a bit more than most manual allow but this particular load is WAY powerful and I hate em in my Ruger #1 let alone a less stoutly built trapdoor.

I hesitate posting the grains of this powder as I'd surely hate to see or hear of a newbie with a bit less experience with these old shooters.

Please be careful with these old sweethearts.

[salpal48]

I have seen This many Times @ ranges.. Guys who Claim there Loaders ,Pushing Old BP rifles to The max and Having Trouble.
I don't Give advise, Whatever happens makes No difference to Me. as Long as I am not Next to them

[Outpost75]

I shot an original 1884 Trapdoor for years and 50 grs. of IMR-3031 with a 300-grain jacketed bullet does not exceed SAAMI MAP and is a safe load, although jacketed bullets are hard on the old soft steel barrels.

Data from Lyman Cast Bullet Handbook, 4th Edition (2010) p. 214 lists the following Trapdoor Loads:

#457191 292 grain #2 alloy, OAL 2.55" 48 grs. IMR3031 1467 fps, 11,400 cup; 53 grs. 1706 fps, 16,800 cup

#457122 330-grain #2 alloy, OAL 2.55" 43 grs. IMR3031 1338 fps, 10,600 cup; 47.5 grs. 1532 fps, 15,300 cup

#457124 385-grain #2 alloy, OAL 2.54" 40 grs.IMR3031 1254 fps, 9,100 cup; 44.5 grs. 1449 fps, 15,800 cup

Lee #457-450F #2 alloy OAL 2.85" 37.2 IMR3031 1209 fps, 12,500 cup; 41.3 grs. 1372 fps, 16,500

#457125 500-grain #2 alloy OAL 2.835" 38 grs. IMR3031 1075 fps, 12,400 cup; 42 grs. 1332 fps 17,900 cup.

[quail4jake]

That load is way over the top for a trapdoor! I load IMR4198 (don't remember how much) behind those 300 gr XTPs @ 2200fps for the repro sharps which handles it fine but it's a big whallop...I'd not like to see that in an Allin action. I hope someone rethinks it...

[Outpost75]

That load is way over the top for a trapdoor! I load IMR4198 (don't remember how much) behind those 300 gr XTPs @ 2200fps for the repro sharps which handles it fine but it's a big whallop...I'd not like to see that in an Allin action. I hope someone rethinks it...

See Lyman pressure tested Trapdoor level loads above and on referenced page if you want other powders.

[bigted]

The load this feller was shooting is WAY above the listed 53 grains IMR 3031. Think very close to the 60 mark and you get my worrie.

[Hardcast416taylor]

I prefer to shoot cast boolets at sane powder levels in my `84 TD. There has never (to my knowledge) been a `J` bullet load fired thru it. I guess it all comes down to not wanting my TD wrapped around my head!Robert

[M-Tecs]

Per the Hodgdon Web site 59.5 grains of IMR 3031 is 22,000 CUP using a Sierra 300 bullet That is well under the 28,000 psi max for trapdoors.
That is a Hodgdon recommended TD load. As Outpost75 stated above jacketed bullets are hard on the soft steel in these old barrels.

Lyman manuals generally stop at 18,000 but the 28,000 PSI SAAMI standard is based on safe Trapdoor loads.

187408

[bigted]

WOWW!! guess he was not that far off the mark afterall. I would have never guessed this.

Ol Elmer once wrote that a 45-70 case clear full of IMR 3031 under ANY bullet that didnt compress it was a very safe load in the Winchester 1886 rifle. Guess i have learned sumptin today.

[Premod70]

The trapdoors as everybody knows were developed for black powder pressures that never run over 18,000 psi and that is on a good day. The pressure curve for black powder is a spike and the fastest smokeless powder is a long gradual curve in comparison, the longer time for strain overtaxes the very low quality metals of the trapdoors. The loads of IMR 3031 discussed here will eventually destroy a trapdoor and the shooter as well. Do yourself a favor and heed Lyman's loads or better yet shoot black powder; pushing the limits has no purpose, there are too many Ruger #1's out there to think otherwise.

[M-Tecs]

The loads of IMR 3031 discussed here will eventually destroy a trapdoor and the shooter as well.


Someone needs to inform SAAMI, Hodgdon and the ammo manufactures that they are wrong on what the SAAMI spec for the 45/70 should be.

SAAMI was founded in 1926. Total about 700,000 TD's were produced. This is just a guess but I am fairly certain that TD's out numbered all other rifles chambered for the 45/70 when SAAMI came up with the 45/70 spec. Other than the H&R TD's I am not aware of any Factory rifles chamber in 45/70 between 1935 when Winchester dropped the 86 and Marlin intoducing the 1895 in 45/70 in 1972. The SAAMI 28,000 spec. was targeted to the TD.

In the Army testing for 30/40 Krag cartridge use in TD's a couple of thousand rounds of 40,000 CUP did produce frame stretch.

Trapdoors are stronger than most believe. I purchased a TD from an individual that got a deal on 5,000 rounds of 405 grain jacketed Winchester factory ammo. He fired over 4,000 rounds through it. At the time I read factory 45/70 was under Max but well above 20K. When I purchased it we installed a Douglas barrel on it and put over 20K of cast and about 500 jacketed throught it. The action is still very servicable and a lot of those loads were above the 22,000 PSI in the video. With SAAMI spec. and under loads the only thing that will destroy a TD is wear.

http://www.trapdoorcollector.com/cgi-bin/afrasca/bulletin/config.pl?read=16056
For a detailed modern attempt to blow up a Springfield 45-70 look in a copy of the GUNS ILLUSTRATED 1996 28th. edition annual. It took quite a bit of effort to cause damage. The final load was 50 grs. of bullseye and a heavily crimped 500 gr. bullet and at that the damage was less than would be believed. OH, do not try this load at home they were professionals.

http://www.trapdoorcollector.com/cgi-bin/afrasca/bulletin/config.pl?read=16056

https://www.loaddata.com/Cartridge/45-70-Government-Trapdoor-Rifles-Hodgdon-Data/6782

http://www.ballisticstudies.com/Knowledgebase/.45-70+U.S+Government.html

http://www.shootingtimes.com/ammo/ammunition_ballisticians_notebook_the_45-70_government_100710/

http://castboolits.gunloads.com/showthread.php?61694-Trapdoor-Strength

http://castboolits.gunloads.com/showthread.php?196900-45-70-Trap-door-official-SAAMI-pressures post #4 has actual tests.

http://www.trapdoorcollector.com/cgi-bin/afrasca/bulletin/config.pl?read=16184

http://www.freerepublic.com/focus/news/843705/posts

From Hodgdon on the use of 3031 in Trapdoors. The load in question was a different load, however, the reply adresses TD pressure.

All of our data is developed using SAAMI spec. pressure barrels and we abide by the pressure standards set by SAAMI whether they be CUP or PSI.

SAAMI CUP standards for the 45-70 Government is a Max Average Pressure of 28,000 CUP. As you can see the load in question is well below the SAAMI MAP for the cartridge. The bullet was a hard cast plain base lead bullet made by a local company in business here locally at the time.

IMR 3031 is of an appropriate burn rate for this application and due to its grain structure ( a fairly long extruded granule) it will of course have what I would consider a great loading density (case fill).

Understand that it’s not my job to critique or even comment on loading data created by others. The load in question like all of the Trapdoor data we currently have published has stood the test of time and we stand behind it as we do with all of our data.

Dave Campbell

Customer Service Representative

Hodgdon Powder Company

6430 Vista Drive
Shawnee, KS 66218
913-362-9455 Ext. 117
dcampbell@hodgdon.com

Correlating PSI and CUP. For the 45/70 CUP and PSI are the same 28,000
https://www.shootingsoftware.com/ftp/psicuparticle2.pdf

http://saami.org/specifications_and_information/publications/download/Z299-4_ANSI-SAAMI_CFR.pdf page 22

[bigted]

I do know that Wolf, in his book published BP loads above the Lyman spec's for trapdoor design rifles. If memory serves ... The top BP loads are 28+ k in pressure. The 1898 loads of IMR 3031 being 40 grains under the 500 grain boolit ... This produced 26,700 cup MAX pressure. Interestingly ... The 3Fg 70 grains load under the same 1881 500 grain boolit produced 29,600 cup pressure ... These are armory loads in original old trapdoor rifles.

[John Allen]

I just use black powder it is what they originally used why change? I will stick with the holy black.

[Chill Wills]

The trapdoors as everybody knows were developed for black powder pressures that never run over 18,000 psi and that is on a good day. The pressure curve for black powder is a spike and the fastest smokeless powder is a long gradual curve in comparison, the longer time for strain overtaxes the very low quality metals of the trapdoors.

I am not sure the part I highlighted in red is accurate.

I have seen time/pressure traces for BP and a number of different smokeless powders. I do not have them to post.

If my memory is still good, I think the range of smokeless powders bracketed the black powder.
Black certainly reaches peak fast and tapers off.
Again, from what I think I remember; On the very fastest end of smokeless pistol powders, peak pressure climbed faster.
Most of the medium powders and all of the (slow) rifle powders took longer to peak.

I am no metallurgist however regarding the text above in blue, I think that the slower impulse to max safe pressure stresses the metal the least.

Just one layman comment about the old Springfield's and any/all the old rifles we like to shoot. No one knows what kind or how many rounds have been shot through some of these old rifles and metal fatigue is always on my mind.

[Tom Herman]

Chill,

I saw some graphs of black powder vs. smokeless rise times posted here a few years back.
IIRC, the black powder (2F) was actually a slow rise time, and the Trail Boss had a much faster rise time and a greater peak pressure (by several factors).
There were also graphs of I believe IMR 4198, which showed an almost identical rise time and pressure as 2F...
My take away from this, was to avoid fast rise time, high pressure spike powders, and stick to either 2F or those powders that emulated a Black Powder ignition curve and pressure characteristics.
There were four powders listed as being acceptable, and I settled on the 4198 as it appeared to be best (it certainly is what is listed in most of the Cartridges of the World smokeless loads for BP rifles), and unlike 3031, it was actually available locally!
I've used it to case form 11mm Danish Remington from .45-70 casings, and I'm still here to tell about it.