Accuracy?

[Skychief]

The farthest I've grouped mine, sans a rear sight, was 60 yards.

From a rest, the gun will print 3 1/2" groups.

Without a rest at that range? Ha! Not even in the neighborhood, but that's ME, with THAT gun.

Good luck, they're an addiction, Skychief

 

[smo]

The farthest I've grouped mine, sans a rear sight, was 60 yards.

From a rest, the gun will print 3 1/2" groups.

Without a rest at that range? Ha! Not even in the neighborhood, but that's ME, with THAT gun.

Good luck, they're an addiction, Skychief

Sky, at least you know what it's capable of. :thumbsup: I haven't managed to get mine that close yet. More tinkering to come...

 

[Skychief]

Exactly smo! :thumbsup: I most certainly haven't mastered the offhand shooting of it though. I can't come close to shooting it as accurately as my shorter, lighter weight guns.

A lot more practice is needed, for sure! :surrender:

Best regards, Skychief

PS, I wrote a thread about finding the load that shot the small groups, titled 'Roundball Nirvana'. Might be of interest to some, including the OP.

 

[Toomuch51]

In a competition situation I have found that most smooth bores can (off hand & PRB & no rear sight) pretty much keep up with a rifle out to about 40 - 50 yd. with game getting accuracy to 80 - 100 yd.
By this I reference coffee cup groups (aprox. 3") at 50 yd. and saucer (6 - 9") at 75 yd.

Of course this was when my eyes still worked right.

 

[RAEDWALD]

All other things being equal the distance at which the ball becomes unstable from a smooth bore is a function of the speed of the ball and it's size.

Not wanting to encourage unsafe loads but the larger the load the faster the ball starts out. So the further before it slows enough to enter the transonic zone, whereupon it will become unstable. A larger ball, at the same muzzle velocity, will maintain it's speed further than the lighter smaller ball by virtue of it's greater mass to surface area.

A round ball ballistics calculator that lets you vary bore and charge will demonstrate this. Though not all calculators allow for the range of velocities which are transonic. It is a wide range on either side of the actual local speed of sound.

Like all things black powder; the answer to your question is the broad principle above but the old variables of wind, powder, windage, weather and so forth rarely causes them to answer to the helm as predicted. Then there are the trade offs such as recoil for extra speed and/or size, extra heat haze in a string of shots with more powder burned in a wider barrel and doubtless more.

At closer ranges accuracy can also be found with a light load in a smaller bore which starts out slow enough to never become transonic let alone supersonic although this can be sensitive to wind.

 

[Loyalist Dave]

..., clover leaf groups at 50 yards, and very decent groups at 70 yards, but 100 yards, forget it

The British Army used to award a soldier who, after fashioning custom rounds for his musket, hit the target 5 out of 6 shots at 90 yards. The badge was a green plume or "flash" on his hat at his cockade, and designated him a "marksman". They didn't award many of these "badges".

The target was a 2' wide, 6' tall rectangle, and a hit anywhere counted. :shocked2: I guess if you smacked a fellow at that range anyplace with 3/4 ounce lead ball, or a heavier one, it would take the "fight" out of him, eh?

Sorta gives you an idea what the British Army thought was a proper range for accurate smoothbore fire.

LD

 

[tenngun]

Even hunting falls in to that thinking. Most of us want quick clean oneshot kills. However a fat ball though a deer will put meat on a table, even if you have to track the deer for a day, something we would not want to do today.

 

[Rifleman1776]

Mounting and sight picture the exact same from shot to shot

Yep, hold and sight picture. IMHO, most fowlers are not designed, or made, for rifle accurate shooting. I have not yet developed a consistent hold or sight picture with my fowler. My groups are sometimes good but can be at different places on the target. Now, almost a year of not shooting anything due to surgeries and other illnesses, I'll be starting over and need to learn wat works for me.

 

[hanshi]

I will also admit that a smoothbore can be quite frustrating to find a good load for: prb, unpatched, etc. I try to find the most consistent load even though it may not be the most accurate. A load that throws one or two fliers out of five shots, IMO, is worthless even if three of those shots make a tiny group. I now shoot three shot groups with the smoothbore rather than five shots. Sometimes five shots do okay but would I really get all five in the bush?

 

[George]

Sometimes five shots do okay but would I really get all five in the bush?

But...but...what if the first shot in the bush is the dreaded flier?

Spence

 

[George]

So the further before it slows enough to enter the transonic zone, whereupon it will become unstable. A larger ball, at the same muzzle velocity, will maintain it's speed further than the lighter smaller ball by virtue of it's greater mass to surface area.

It's an interesting theory, and if it were true, it might explain at least some of the problem. For me, it never pans out in the field. Maybe you can answer the question which always occurs to me when I shoot my smoothbore at long distance. If the theory is true, why don't I see it messing up my shots the same way it apparently does for other shooters? My flintlock smoothbore has a MV of 1475 fps, well above the speed of sound, and at 100 yards still has almost 1000 fps, well below the speed of sound. So, my balls always pass through the trans-sonic zone, but they never suddenly fly off god knows where. I've never seen that happen, and thus my question.... why don't my results in the field ever show the theory in action?

Spence

 

[azmntman]

I believe you live right :idunno: :slap:

 

[Artificer]

Spence,

I think the wad you load before you load your PRB has something to do with the accuracy you have found.

Also, if you have a very definite "spot weld" or position of your cheek on the stock when you shoot, that will also greatly enhance accuracy.

Do you use some point on the breech to align the barrel to the front sight when you shoot?

Gus

 

[George]

Gus, whether or not I have a proper weld or a wad system which works unusually well is not the point. Whatever problem the trans-sonic turbulence might cause re accuracy happens after the shot is fired and the ball is in the air, and if the theory were correct, would happen regardless of any wadding system or aiming and shooting practice. A perfect wadding system, total gas seal, etc., and a perfect performance by the shooter would all be completely wasted, the ball would still turn left halfway to the target. It would also still happen if you strapped the gun or just the barrel into a totally immoveable rest in order to completely eliminate the human element.

The trans-sonic turbulence problem, whatever it is, is not a shooter problem. It's also not a gun problem. If you fired the ball from any kind of mechanism that gave it the same muzzle velocity, with air pressure or centrifugal force...whirling rock on a string...for example, it would still happen.

Spence

 

[Artificer]

Spence,

I am not sure if "trans-sonic turbulence" is a real or noticeable problem with ML'ers and especially the large round balls most of us shoot in smoothbores. There are plenty of other things that will cause inaccuracy both before and after a ball leaves a smoothbore gun, even at the comparatively short ranges (125 yards or normally less) that most of us shoot.

As you remember, I have often written about the two accuracy loads in most ML guns. One very light charge that that the gun likes and can be used for target work at 25 and sometimes 50 yards w/a smoothbore and a heavier charge for hunting. Now the fact that with a light charge that one will get good accuracy with at short range, may come from the fact the ball is subsonic all the way to the target. However, it may be that barrel harmonics are very smooth and even with light charges. I don't know which is more important, but I suspect the latter.

If "trans-sonic turbulence" was something noticeable, I would expect accuracy to get better as we put heavier charges of powder and this even beyond the heavier accuracy load for hunting. But in the real world, once one hits a certain point with a heavier charge, increasing the powder charge only makes the groups open up wider.

Gus

 

[Artificer]

Spence,

I am not sure if "trans-sonic turbulence" is a real or noticeable problem with ML'ers and especially the large round balls most of us shoot in smoothbores. There are plenty of other things that will cause inaccuracy both before and after a ball leaves a smoothbore gun, even at the comparatively short ranges (125 yards or normally less) that most of us shoot.

As you remember, I have often written about the two accuracy loads in most ML guns. One very light charge that that the gun likes and can be used for target work at 25 and sometimes 50 yards w/a smoothbore and a heavier charge for hunting. Now the fact that with a light charge that one will get good accuracy with at short range, may come from the fact the ball is subsonic all the way to the target. However, it may be that barrel harmonics are very smooth and even with light charges. I don't know which is more important, but I suspect the latter.

If "trans-sonic turbulence" was something noticeable, I would expect accuracy to get better as we put heavier charges of powder and this even beyond the heavier accuracy load for hunting. But in the real world, once one hits a certain point with a heavier charge, increasing the powder charge only makes the groups open up wider.

Gus

 

[George]

I agree that it's unlikely trans-sonic turbulence is a factor in ML accuracy. I don't know enough modern physics to understand why that might be the case, but it has without question been my personal experience.

I feel the same about the usual culprit blamed for the supposed inherent lack of accuracy in smoothbores, the dreaded knuckleball effect. I've shot a lot of smoothbores and have never seen it.

While I'm swimming upstream I might as well take a few more strokes...it has also never been my experience that BP guns of any type have only two accuracy loads, one heavy and one light.
I choose the power level I load for by the trajectory I want, and so far I've never had a problem getting good accuracy with whichever load that turns out to be, high, low or middlin'.

Spence

 

[54ball]

Smooth bore shooting has been compared to primitive bow shooting. It requires practice.
This is something I have discovered in my smoothnore shooting, It's a far better point and shoot gun than a pin point piece of precision equipment.

Example.....
Let's say you are shooting at a Buff target at 55 yards. You make a hit time after Time after time. The group may even be impressive.

Now try to shoot a target the same size as the group you just shot on the "Buff" target. Instead of the large Buff, your shooting at a dinner plate...Maybe a little smaller. Now there are misses time after time.

I think a lot of this has to do with sight limitation both on the gun and the capability of the shooter. I found the single bead just seems to go away at 55-60 yards. If the barrel is very hot ....forget it, the mirage will distort and stretch my single bead sight into infinity.

I much prefer a smooth bore with a rear sight. While I could hit consistent with just the bead I found my success in hunting to be less than impressive. My problem was position. With a rear sight I found the gun much more forgiving as far as shooting position.

Make no mistake though, it's still a smoothbore with all it's quirks. The addition of rear sight does not make it a rifle.

 

[tenngun]

I have a rear sight on my fusils, most of the time I get palm sized groups st fifty yards, I still get flyers but would keep it on a dinner plate, or boiler room of a deer.

 

[hanshi]

That is just about how it works for me, too; hand size groups at 50 but with occasional fliers. But usually the fliers only open the group two or three more inches.