Reloading .45-70 Trapdoor Carbine

[4fifty8]

• model S900 Trapdoor Carbine Pedersoli modern re-creation https://www.davide-pedersoli.com/en/product/springfield-trapdoor-carbine-22
• referenced Trapdoor load data Lyman Cast Bullet Handbook & Speer manual #14
• target load 405gr CamPro / 1.9cc~24.5gr 2400 / BR-2 / Starline brass
• hunting load 500gr Hornady / 32gr Re7 / BR-2 / Starline brass
• ***safe in my rifle only***
• adjustable rear sight & fixed front sight
• figured out hold for 500gr ok at close range off hand
• rear sight ladder raised figured out hold for 405gr consistently hit 100m 6" dia. gong off hand
• lotsa fun

 

[dan belisle]

I have an H&R version. They are fun guns, just avoid stout loads. - dan

 

[fingers284]

I have an H&R version. They are fun guns, just avoid stout loads. - dan

Yaup...three shooters in my club have replica Trapdoors, two of them H&R and one Pedersoli and all of them have had trapdoors fly open when fired. All with smokeless powder but none that I would characterize as 'stout loads.

 

[Snider shooter]

Having trap doors fly open is one of two things. Defective gun or loads that are over pressure for a trap door. I have an original TD and it hasn’t opened up during firing with black or smokeless loads. The one H&R I seen fly open was using loads meant for win 1886 rifles. Modern made TD’s aren’t any stronger than the originals, it’s due to the design.

 

[4fifty8]

According to Speer manual #14 original 1873 Trapdoor Springfield rifles in good condition loads should be held to 21,000 CUP max.

Manufacturer rates S900 @ 31,908 psi maximum operating pressure. I have fired .45-70 Marlin level loads (SAAMI 28,000 CUP max) no problem in my S900.

 

[dan belisle]

[/B]

Yaup...three shooters in my club have replica Trapdoors, two of them H&R and one Pedersoli and all of them have had trapdoors fly open when fired. All with smokeless powder but none that I would characterize as 'stout loads.

My 1886 loads can't be used in my trapdoor. Way too much for that design. I just load them down. - dan

 

[4fifty8]

Today checked off hand accuracy at 50m with CamPro 405gr / Alliant 2400 @ 1425 fps mv. Fun plinker.

 

[4fifty8]

Today checked off bench accuracy -

• CamPro 405gr / Pyrodex @ 1325 fps mv - smoky...
• Barnes 400gr SSP / 2400 @ 1250 fps mv
• rear sight ladder raised to use aperture - challenging

 

[QueensHorseman]

I’ve been considering a pedersoli trapdoor. Thanks for your posts.

 

[4fifty8]

^^
Much appreciated.

Pretty good quality & fun shooting, would be a hoot to down game with.

Historical note original Springfield Model 1873 cavalry carbines designated as .45-55.

"Cavalry units armed with the Sharps carbine were re-equipped with a carbine version of the M1873, which had a reduced barrel size of twenty-two inches. It fired a variant of the .45-70 cartridge, the .45-55, with a reduced powder charge of fifty-five grains as opposed to the normal seventy grains." https://armyhistory.org/the-springfield-model-1873-rifle/

 

[dan belisle]

^^
Much appreciated.

Pretty good quality & fun shooting, would be a hoot to down game with.

Historical note original Springfield Model 1873 cavalry carbines designated as .45-55.

"Cavalry units armed with the Sharps carbine were re-equipped with a carbine version of the M1873, which had a reduced barrel size of twenty-two inches. It fired a variant of the .45-70 cartridge, the .45-55, with a reduced powder charge of fifty-five grains as opposed to the normal seventy grains." https://armyhistory.org/the-springfield-model-1873-rifle/

Good to know, thanks. - dan

 

[4fifty8]

Visited Little Bighorn Battlefield National Monument, Visitor Center & Museum a few years ago. Fascinating step back in time. https://www.visitmt.com/listings/general/battlefield/little-bighorn-battlefield-national-monument