Looking for a Bullseye Powder load in the 45/70

[brstevns]

Looking for some Bullseye powder loads for use in a ruger #1 45/70. Something around 1100-1200 fps using a bullet weighing 430gr if possible.

[Outpost75]

Can't help you on a 1100-1200 fps, but for a subsonic load for use with a suppressor 10 grains of Bullseye with #457122 gives about 1000 fps. I do not recommend a heavier bullet or powder charge in the .45-70 with Bullseye!

[brstevns]

Can't help you on a 1100-1200 fps, but for a subsonic load for use with a suppressor 10 grains of Bullseye with #457122 gives about 1000 fps. I do not recommend a heavier bullet or powder charge in the .45-70 with Bullseye!

Thanks, was wondering about the heavy bullet, Maybe I could use the Lee 340 gr. ?

[Outpost75]

Thanks, was wondering about the heavy bullet, Maybe I could use the Lee 340 gr. ?

I would think that should be OK, especially since the Ruger is a strong action, but I would be inclined to reduce the charge initially by a grain or so, fire a couple at first to make sure that bullets indeed exit the barrel, then if all appears well, fire ten over the chronograph and look at the velocity variation, firing 5 rounds powder forward and the other 5 rounds powder back. In a pooled sample of 5 rounds each fired "nose tap" vs. "base tap" if the combined sample standard deviation exceeds 5% of the mean velocity, you will then need to use a fluffed tuft of Dacron, about 1 grain, preferably WEIGHED, then tucked LOOSELY into the case to occupy the free airspace, and try again to see if the pooled velocity standard deviation is reduced to something within 1-3% of the mean, which is entirely acceptable.

Whenever using an inert space filler in a straight case it is absolutely essential NOT to poke the filler down against the powder, and to use the minimum amount, which when fluffed, prevents the powder from migrating past the filler, AND in which the fluffed, inert filler is COMPLETELY consumed upon firing, with no visible fibres being ejected from the muzzle. Failure to adhere to these precautions may result in the filler material acting like a projectile, and the bullet base behaving as if a bore obstruction, causing a ring bulge in the chamber.

Ideally you want to select a powder which ignites easily and tolerates the free airspace in the case, producing uniform velocities. Bullseye generally meets these requirements in well balanced loads, but in longer, heavier bullets you may get pressure spikes as the bullet base upsets into the throat and deforms before the front end of the bullet starts moving. I ringed the chamber in an 1884 Trapdoor once that way, so beware once bullet weight in a .45-70 gets above about 320 grains, fast powders in a large case can spike...

[Kosh75287]

Bullseye generally meets these requirements in well balanced loads, but in longer, heavier bullets you may get pressure spikes... I know that Bullseye CAN be used for the application you mention, but you may find that a slightly slower-burning powder like Unique will be more forgiving in your work-up. In the range of 9.5-14.0/Unique/435gr.Cast would probably work just as well, and be easier to work up. You can STILL get yourself in trouble using Unique in a large rifle case, but I'm of the opinion that loads using it as a propellant will display earlier and more overt warning signs of pressure spikes than Bullseye is likely to. JMHO.

[Outpost75]

I know that Bullseye CAN be used for the application you mention, but you may find that a slightly slower-burning powder like Unique will be more forgiving in your work-up. In the range of 9.5-14.0/Unique/435gr.Cast would probably work just as well, and be easier to work up. You can STILL get yourself in trouble using Unique in a large rifle case, but I'm of the opinion that loads using it as a propellant will display earlier and more overt warning signs of pressure spikes than Bullseye is likely to. JMHO.

Agreed, but the OP asked specifically about Bullseye and I was trying to give the benefit of my experience.

As for Unique, I have used it for step-down ballistics testing in cases as large as the .50 BMG down-loading the APIT M20 bullet to the lowest velocity which would exit the barrel of a manually-operated M2HB, but that is another story...

[brstevns]

Thanks guys. I will use Unique for the heavy bullets and keep Bullseye for the 300-340 gr ones.