Springfield Trapdoor 45\70 ??
I took in on a trade over the weekend a very nice trapdoor rifle that has been customized into a carbine. It is a very clean, tight, weapon with a great bore. My question is regarding ammo, as I would like to shoot it. Is the modern off the shelf 45\70 ammo safe to shoot in these old guns or do I have to use black powder re-loads. Thanks guys for any input on this.

Use ammo marked 45/70 Government!

Like Njret said 45/70 Government Dustin

While the factory loads are probably safe in this rifle, I'd personally use blackpowder handloads. Given this is a relatively weak action even by 1800s standards, it would be safer to use blackpowder loads.

i use factory loads in mine all the time, as these are loaded well below what is capable for the cartaridge, never a problem but i watch for signs on the cases for danger. and as stated above make sure the y are GOvERNMENT

As others stated, buy 45/70 Government marked ONLY. Do NOT buy 45/70 marked for MARLIN because it is way too hot. I shoot factory loads all the time in my 2 original trapdoors. BP loads are good IF using it for cowboy action shooting but if hunting with it I personally would want factory loads due to the smoke from the BP loads NOT allowing you to see the game for a minute or two. Now as to the 45/70 MARLIN marked loads, they are for Marlin lever guns and great for Sharps rifles. IF you decide to keep it, buy the dies and begin reloading, you will find it a joy to shoot.