Any thing in the neighborhood of a slingshot to a .800 blunderbuss?

 

Specific questions bring specific answers.

 

Any caliber, any bullet weight, any rifle-that produces reasonable/competitive 1000 yard bp accuracy.



joe b.

 

ALL the records are held by the U.S. Gov. 45-70-405 so there's no doubt they work, but its just one of a hundred or more that are capable.

 

So, do you have any MV/BC data?

 

MV with BP cartridges is highly variable with barrel length and other factors. Cartridges of the world says 1350 fps with 30" barrel.
BC is surely known but I don't have it handy. BC of about 250 would be expected.

 

Lots of credible information online.


I'm afraid that asking for muzzle velocity and ballistic coefficient is just barking up the wrong tree. See what people are using and imitate that, as best you can. It is a different world than 1,000 yard competition with smokeless powder/cartridges.


This might help: Long Range BPCR .com Home Page

 

With BP the velocity is directly related to the case size, bullet weight & barrel length. In other words, a 45-70 takes 70 grains of BP or there abouts to fill the case so the bullet is against it with no air space. So the weight of the bullet & the barrel length will vary the velocity. Same with the other BP rounds like the 45-90, 40-65 & the host of others out there. Long heavy bullets do better at long ranges than short light ones. I don't think I have ever heard anyone at a BP shooting event mention muzzle velocity or BC, as they are irrelevant compared to bore size & how the bullet fits, what bullet your rifle likes best, lubricant used, seating depth, etc, etc. When the apex of your trajectory is 40' above your line of sight, BC becomes a mute point. As MikeG says, "Your barking up the wrong tree". Shooting long range BP is a world unto itself.

 

The heavy bullets carry at distance very well but they sure have to be aimed high. I have a 45-70 Browning BPCR and find the Rapine 500 gr gov't bullet shoots best. It is a hard gun to work with. Almost a micro groove so I need at least .460" bullets. Velocity is limited and adding more powder just reduces it. Adding and compressing more just adds to bullet weight until it will not all burn so flares exit the muzzle.

With smokeless from my 45-70 BFR revolver is faster and even at 500 meters I have to aim at a tree branch an estimated 26' above steel. At 1000, you need to scrape the moon.

I can only say it is a lot of fun. I once shot a 2-1/2" group at 500 with the revolver.

Work for accuracy and find the sight setting for 1000 is the best you can do.

The browning sight is top notch and Kermit made me an adjustable iris so I can change the hole size. My front sight has inserts to change. Now if I just had a 1 in 16" twist rate or so. Need a lot of spin for long ranges.