14 April 2022, 22:21
RJM.@Jax.FL35-40 or 38-55 barrel length on BPCR silhouettes
What is
....Good,
......Better,
.........Best,
a 26"
a 28"
or a 30" Barrel
14 twist..
Shooting a 35-40 or 38-55 using Black Powder
on silhouettes.
Exclude sight radius considerations.
Clearly the 30" barrel providing a 34" sight radius would be better using a verier tang sight but at what length would the best velocity be obtained.
I know from other research that an increase of about 25 fps per inch is obtained shooting smokeless but not sure if the same holds true for BP
THX for your comments...
RJ
Even more so; if by "best" you mean "most", then 30 inch. If by "best" you mean
most efficient" then it is much less.
Go with the 30 inch. No reason not to as long as you make weight.
15 April 2022, 04:59
RJM.@Jax.FLDPCD,
Thanks..!
Describe "Efficient" please...?
Faster I get... but efficient ...?
I believe harmonics is more of a factor the longer barrel you go...
That being said I want to try to keep whatever bullet I'm using just above the transonic range out as far as I can, if for nothing else stability.
I wonder if the point of diminishing returns
can be calculated with 45-50 grains of Swiss 1 1/2 in a 35 or 38 caliber barrel with projectile weights the same..
Thanks again for your input.
RJ
quote:
Originally posted by dpcd:
Even more so; if by "best" you mean "most", then 30 inch. If by "best" you mean
most efficient" then it is much less.
Go with the 30 inch. No reason not to as long as you make weight.
Don't worry about harmonics in a BP rifle. Efficiency is gain per inch. Or gain per grain. Since you mention diminishing returns, you already know what it is.
Go with the 30 inch. That is what I use.
19 April 2022, 13:17
RJM.@Jax.FLThank You both.. !
quote:
Originally posted by dpcd:
Don't worry about harmonics in a BP rifle. Efficiency is gain per inch. Or gain per grain. Since you mention diminishing returns, you already know what it is.
Go with the 30 inch. That is what I use.