My gunsmith have two rifles built on ruger no 1 for sale. Both have a weight of 10 pounds with a 26" heavy barrel. One of them is in caliber 45-70 and the other is in caliber 45-90. The cost is the same for both.

I don�t know what to choose. I plan to use 350 grains and 405 grains bullets from Woodleigh and like to get 2200 fps and 2100 fps out from it. I don�t know if it�s possible to reach this out from a 45-70 without to get to much pressure. Maybe there is not place for powder enough in that case.

I know that the ruger no 1 is good for very high pressure, but maybe the caselife gonna to be very short. If I choose 45-90 I can use starting loads for 458 WM and get very low pressure and reach those velocity.

Anyone here who knows about load data for those bullets and 45-70 or 45-90?

Wich one shall I choose?

You can get factory ammo in both calibers from PMC.
I stock them both and it is pretty reasonably priced.
If you want something cool and old western, go for the 45-90.
I have a reamer in "458 RCBS" also known as 45-120 so you should not have a problem finding someone to chamber for you.

-Spencer