SxS round ball shooting

[Britsmoothy]

Um, on a pattern board, how else? Though I could have written more clearly, as the patterns aren't so much "messed up" as "moved" in most cases. I find them "messed up" because it makes it harder to hit with them when using shot.

I patterned my current 11 gauge gun prior to filing the muzzles to regulate POI for ball. My shot load consisted of 4 1/2 drams of Fg, 2 card wads, #4 shot equal in volume to the powder, 1 overshot wad. With the bead centered in a 30" circle at 30 yards, about 65% of the shot stayed in the 30" circle (pattern from the left barrel was a bit low, right barrel was a bit high, but both were centered on the vertical axis).

After filing the muzzles to regulate POI of a ball load at 50 yards, I again patterned the gun in the same manner at the same range. Pattern from the left barrel had moved up and hard right, and was now appx 30% in the circle, most of it hitting outside the circle at roughly 2 o'clock. Pattern from the right barrel had moved slightly down and hard left, and was about 50% in the circle centered on the edge of the circle at 9 o'clock. It is no longer a gun I would chose to take birding if I had an option.

Ahh I see. So you just meant the filing moved the pattern, not messed the pattern.
Yes, filing to move a ball may not correlate the same for a shot load

 

[smo]

Doesn’t that seem strange?

It’s my understanding that filing the barrel too move impact of a smoothbore is caused by the redirection of gasses as the load leaves the bore.
Unless one load (shot) is heavier than the other…(ball)
I would have thought it would it would shoot both too the same point of aim..

 

[Britsmoothy]

Doesn’t that seem strange?

It’s my understanding that filing the barrel too move impact of a smoothbore is caused by the redirection of gasses as the load leaves the bore.
Unless one load (shot) is heavier than the other…(ball)
I would have thought it would it would shoot both too the same point of aim..

Yes sir but,....
Many other things are going on too.
Acceleration forces may be different, the pressure curve/dwell/time difference between the two projectiles etcetera.
Muzzle position as the recoil force or inertia starts etcetera.

 

[smoothshooter]

Bores are roughly .753" (some variance due to wear/corrosion/etc). Shooting a nominally .735" roundball from a Lyman mould, actually mic's about .738" when cast in scrap lead salvaged at the local range. Current load uses an 11 gauge Circle Fly overshot wad with a slight nick in the edge to allow gas to escape, followed by a patched (patch thickness .017-.018", lubed with neatsfoot oil) round ball. Average of the 10 most-recent 10-shot groups is 5.69". I've been saying for years i need to put better sights on the gun, just haven't got the final "push" to do so, the bead works well enough for what I do with it.

This is basically the load column I used in my Brown Bess, after burning up several hundred pounds of powder over the course of several years of testing. My experience has been that a load that generally works well in a single-barrel fowler or smooth rifle will usually work with some fine-tuning in a double. Most people aren't going to file the muzzles to regulate the gun (it messes up shot patterns), so they work up a load for whichever barrel shoots closest to point of aim.

At what distance were you shooting your ball groups?

 

[LongWalker]

At what distance were you shooting your ball groups?

I used the old trick of filing the muzzle to regulate it, and can usually keep 10 shots ( 5 "right and left" combos) on a paper plate at 50 yards--I know if I miss, it is me rather than the gun/load.