Im new to the blackpowder game,Im Trying to get some loads for the long haul together,Got some excellant ones out to the 200 yardline,But im curious,What velocity am im looking for for the long range stuff?Im hopeing to go to 1000 yards very soon And was wondering what velocity range should I need in the 45,s for that range?Ive got a 45 70 and 45 90,Would like to walk them both out.
Any help would be most appreciated.

Wow,  1375 with 540grs is AWFULLY fast for a BP rifle!  1300 would be more than enough (and a more realistic goal with a 45-90).
I'd try for a minimum of 1200fps with a good design (good BC) bullet - the lower your MV, the better your ES will need to be.  Anything higher would be better, of course - as long as your ES continues to be good.
And yes, the 45-70 can do it, no issues there - I know some people shooting with MV's in the 1170's and getting more than decent LR results.
FWIW, a heavy bullet is not enough - you need a bullet that is aerodynamically efficient and stable at those ranges.

Jeff4570,

Welcome to the wonderful world of Black Powder shooting. 

As a newbie to this there is one thing you should be aware of, assuming that is, that you are not 'au fait' with it already. 

In loading Black Powder cartridges. there should never be any airspace. If the powder charge and a lube disc do not meet the base of the fully seated bullet then that space must be taken up with Cork, Card or Felt wads.

Failure to do this can and does cause 'ringing' of the barrel. This is not a musical note, but damage which can spoil accurace and or make extraction of fired cartridge cases difficult if not nigh impossible. There is no such thing as a 'squib load' in BP cartridge shooting

If your in a gunclub, there are almost certainly others shooting Black Powder, you can learn a lot just by watching and asking questions.

Black Powder shooting is an addiction, and there is no cure. 

Harry

Actually, there's not really a risk with airspace and BP (sorry Harry) - This technique was even advised by W. W. Greener in case of not having a powder of the correct granulation (only too fine) available for loading.  Of course,  that doesn't mean you should use very small amounts of powder in large cases - I personally want at least 70% of the available powder space to be filled.
Still, for competition use, no airspace still is a good idea, as it is a good way to reduce ES and improve general consistency (read accuracy) - and the only way to load without neck tension.
So, if you want to shoot at 1,000, it would be better to heed Harry's advice, even if only in order to have loads that perform.   
I do use loads with airspace, but mainly in cases so big that I either would have to put in such a ridiculously large amount of powder (ever shoot 120grs of Fg in a 577-450 Martini?  Quite an experience...), or just reduce the charge.  A wad column is no option in a bottleneck case, and most fillers potentially even more dangerous.
For match rifle, I use full-case loads as that works best accuracy-wise.  As a rule, the more powder you use, the better the rifle will shoot...

Thank u