Smooth bore accuracy

[Jenrick]

I'm sure this has already been answered, but I'm not having any luck with the search engine here on THR.

When shooting a smooth bore flintlock what accuracy can be expected at 50 through 100 yds? I know shooting a small ball un-patched with a lot of windage isn't going to have very good accuracy, but what about a good fit with a patch? How much effect does muzzle length have on things, besides just sight radius? Compared to flint lock rifles, are smooth bores moderately less accurate, or is the difference mainly when shooting for groups (eg. both perform well enough when hunting that it doesn't really matter)?

Thank you to the BP brain trust in advance,

-Jenrick

 

[arcticap]

I can't provide you with specific answers because every gun is different.
A smooth rifle with rifle sights loaded with a very tight patched round ball (PRB) can be extremely accurate at 50 yards. The looser the PRB then the looser the groups.
I'm specifically referring to the .56 TC Renegades with a 26 inch barrel that can shoot 1-2 inch groups at 50 yards.
Very few smoothbores can shoot as well as a rifle can out to 100 yards. It's not impossible for the best shooters with the best barrels and loads but highly unlikely.
Beyond 60 -70 yards accuracy usually tails offs.
And the tightest loads often require swabbing in between shots to maintain accuracy.
That's why looser PRB's are more often used for ease of loading.

The caliber matters because heavier balls aren't affected by wind as much and carry more inertia to maintain their trajectory. That probably applies to longer barrels too.

Many smoothbores don't even have a rear sight which make consistent accuracy very difficult.
And reproduction flintlock stocks aren't designed to provide the best sighting plane.
With some smoothbore models folks often complain that they don't have a rear sight to use as a reference point when aiming. So their head and eye is never in the same position when aiming for each shot.

What caliber or model are you asking about?
Is it a fowler or is it a smooth rifle that has both front and rear sights?

 

[4v50 Gary]

Like Articap said, every gun is different. With practice, you may be able to hit a man sized target at 75 yards. Author Lawrence Babits did it with his replica Brown Bess. He hit his target five out of six times. BTW, Babits didn't use his ramrod but tapped the butt against the ground to settle the charge and ball.

 

[Mike OTDP]

The MLAIC Miquelet event is shot at 50 meters with smoothbore flintlock muskets. They are getting about 3-inch groups.

 

[Cosmoline]

I concur with the 50 yard figure. It's entirely possible to get a smoothbore that will give good groups or even really good groups at that range. The best would likely be a smooth rifle (rifle furniture and rear sight with a small or medium bore smooth bore barrel) with a tight patch. But something seems to happen beyond 50-75 yards and accuracy falls off badly. I'm not sure what the physics are but it seems to be consistent with the smootbores I've had. For hunting in tight brush where there won't be shots beyond 25 or 50 yards, I don't think you gain anything from a rifled bore.

The advantages are of course very quick and easy loading and the ability to throw all kinds of things in there, from birdshot to buckshot to buck and ball. I've also found that I can roll for quite a bit longer with smooth bores than with rifled bores before fouling gets too bad. Heck the fouling makes the smooth bore shoot better and better.

 

[Akeela]

Firing at army targets in 1860, .69 Cal. smooth bore muskets loaded with Buck and Ball scored more hits at both 100 and 200 yards than did .58 Cal rifle-muskets.
Rifle muskets hit the target seventy-four percent of the time at 200 yards and 98 percent at 100 yards. The obsolete, inaccurate smooth bores charged with B&B hit the 200 yard targets 98 percent of the time and at 100 yards, the buck and ball rounds hit the target 230 percent of the time (more rounds per shot, you see)
The rifle-musket can spit out one ball every 33 seconds the musket puts out 4 rounds in the same amount of time.
For 100 shooters on the firing line, that works out to 300 rounds per minute for rifle-muskets and 1200 for muskets.
On average, Civil War battles commenced at less than 80 yards. At that range, with one ball for your mark and 3 bucks for Area Defense, Buck and Ball rules.
Another advantage for smooth bores is that the danger zone for them is the whole 200 yards (eyeball to ankle - including skipping off the ground like flat stones across a lake), whereas the rainbow trajectory of the rifle musket has a danger zone near the muzzle and one at the end of its trajectory. In between it threatens only birds. Careful sight setting is required to score rifle-musket hits. With smooth bores, one levels the piece, points it at the foe, and shoots. The .69 Buck and Ball is no tack driver at any range, but at the common ranges at which the war was fought, it was absolutely deadly.

Firing B&B over 110 grains of musket powder sends the balls down range flying flat and supersonic.. The balls arrives before before the sound of discharge.

When Col. Mordeci tested musket velocit in 1860 he did it by shooting a small ballistic penduliun at ranges up to and including 500 yards. He got speeds of over 300 f.p.s. at 500 yards and 1400 to 1600 f.p.s. at the muzzle. That means he had to hit his target at up to 500 yards. So much for smoothbore inaccuracy.

A
K
E E L A

 

[Pete D.]

Smoothbores

I have two smoothbores. One is a drop in .54 cal. barrel for my Lyman GPR flintlock. It will give me hand sized groups at 50 yards with little trouble.
The other is a flintlock "fowler" in 20 gauge (.600 RB); it will do the same.

About military smoothies - it is helpful when talking about their supposed inaccuracy to remember that the basic military rifleman tactic at the time - at least for the British - was volley fire. With all of those RBs in the air, individual accuracy was less important.
Pete

 

[1911Tuner]

Theoretically, there's no reason that a smoothbore firing a round ball shouldn't be very accurate. If the ball is perfectly round and mirror-finished, it'll fly true. The problem with smoothbores loaded with lead balls is that...first, the lead isn't smooth. There are all kinds of asymmetrical surface imperfections that catch the air and cause the ball to twitch this way and that.

Then, there's the sudden pressure slamming into the ball, deforming it, and giving the air an even larger area to affect.

Finally, a tightly patched ball will be deformed by the ramrod itself as it's seated. By the time that poor lead ball hits the air, it barely resembles a "ball" any more. It's subject to go anywhere.

 

[zimmerstutzen]

There are competitors out there who can shoot very small groups with their smooth bores, even out to 100 yds. It takes practice, and a thorough knowledge of your gun. At 50 yds with my smooth bore flint lock trade gun I can shoot about a 5 inch group. HOWEVER, with my 50 caliber smooth rifle I can easily shoot 2 inch groups. It has front and rear sights. But at 100 yds the group opens up to a pie plate.

 

[MutinousDoug]

There's a guy whose name escapes me on Youtube that posts videos of himself shooting all kinds of things. One of his vids show him shooting a 12 ga smooth bore slug gun (Bennelli, I think) at a 24"x48" metal sheet or plate. He shoots about 20 times and hits the plate 16 of them. There is no group; he uses the entire plate to get his hits.
I would expect similar accuracy from a .69 cal musket.

 

[Busyhands94]

the best possible combination for accuracy in a smooth bore would be a well made round ball, and a nice tight patch. i have heard fellows at the Civil War reenactments say they live fire their muskets, and they are quite accurate. i have also achieved good accuracy with a smooth bore airgun and lead BBs. nice small groups.

 

[1911Tuner]

i have heard fellows at the Civil War reenactments say they live fire their muskets, and they are quite accurate

Civil War era muskets are rifled.

 

[col.lemat]

???

I always thought rifles were rifled and muskets were smothbored. But then again what do I know I wernt there.

 

[Sam Cade]

I always thought rifles were rifled and muskets were smoothbored.

Yes.

Unless its a rifle-musket.

After the advent of the Minié ball, smoothbore muskets were rifled or fitted with new barrels. That gives you a rifle-musket.
New production weapons of musket pattern with rifled barrels were also rifle-muskets.

 

[col.lemat]

Is some body saying that the smothbore was never used in the war? the quote was the civil war reenactors when live fireing their muskets

 

[Cosmoline]

There are competitors out there who can shoot very small groups with their smooth bores, even out to 100 yds.

In my own experience there seems to be some kind of physics barrier somewhere near 75 yards that makes grouping with a smoothie more and more difficult. The best smooth rifles with perfectly selected and loaded ball and a very steady hand can stretch out, but the challenge mounts with each yard. It's not like a rifle where the basic rules seem to apply at 200 or 600. My knowledge of physics is on par with Gabby Hayes', but there's some other kind of physics involved with the non-spinning projectile. I don't understand it but it definitely seems to throw a lot more variation into the ballistics. Drives some people crazy, others love it. The shooters who can actually pull off tight groups out of smooth bore ML' at 100 and beyond are to my mind among the very best shooters of all. You have to use "the force" to do it, not just rely on the known data from BC and velocity.

 

[Sam Cade]

Is some body saying that the smothbore was never used in the war?

Well sure it was, but the Minié ball made it obsolete long before the war began.

 

[Sam Cade]

My knowledge of physics is on par with Gabby Hayes', but there's some other kind of physics involved with the non-spinning projectile.

That's part of the problem. They do spin. In an unpredictable way.

http://en.wikipedia.org/wiki/Magnus_effect

 

[mykeal]

Not sure why you're citing the Magnus effect. Are you saying the Magnus effect is what causes the ball launched from a smoothbore to spin?

You assert that balls from a smoothbore do spin, unpredictably, then cite the Magnus effect. The Magnus effect is well known and highly predictable - it's the first thing freshmen aerodynamics engineers are taught - so I don't understand it's application here.

 

[Sam Cade]

Not sure why you're citing the Magnus effect. Are you saying the Magnus effect is what causes the ball launched from a smoothbore to spin?

No.

You assert that balls from a smoothbore do spin, unpredictably, then cite the Magnus effect. The Magnus effect is well known and highly predictable - it's the first thing freshmen aerodynamics engineers are taught - so I don't understand it's application here.

The axis of spin that a round ball fired from a smoothbore takes is unpredictable. The Mangus effect generated by this spin accounts for some of the odd behaviors of round ball from smoothbore.

 

[mykeal]

Ok, so what causes spinning about an unpredictable axis? And how do the experienced and successful smoothbore shooters overcome this situation?

 

[Sam Cade]

Ok, so what causes spinning about an unpredictable axis?

Uneven friction as the ball leaves the muzzle,imperfections in the surface of the ball.

And how do the experienced and successful smoothbore shooters overcome this situation?

Better fitting, better finished balls in well lubricated evenly cut patches to start.

 

[mykeal]

Thanks, Sam.

 

[Austin97]

you're not gonna get great accuracy with a smooth-bore at 50 or 100 yards

 

[StrawHat]

The North South Skirmish Association has matches for smooth bores and they do alright. So does the International muzzle loader group. I am not sure what distances they shoot to, but not that close.

I have a friend who has used a 69 cliber Charleville to harvest deer since the 70s. His load is a cast lead round ball with two thin patches. He has won quite a few matches with that load and it is also his hunting load. He has used that load successfully to 100 yards.