| ironoxide |
| (.224 member) |
| 05/09/19 06:50 AM |
On subject of smoothbore vs rifled felt recoil
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I read it in James Forsyth 19th century classic "The sporting rifle and its projectiles". I heard it is mentioned in the Greener's "The gun and its development" and some other 19th century books. I also recently read it repeated on one reputable hunting website that for a given bore size, projectile weight, powder load and gun weight the felt recoil is less in smoothbores than rifles.
Personally I think it is a myth. I have never observed it and I don't understand what kind of mechanism could cause a reduction in felt recoil in smoothbores. 19th century sources claim that as a rifled barrel resists the projectile movement it somehow makes the "push back" of recoil stronger. Although on first look this sounds logical it is not how recoil works. There are multiple components to recoil.
One, the momentum of the bullet being propelled forward against the breech of the gun has to be matched by the gun. Here only weights and velocities of both items matter. The resistance in the barrel plays no role whatsoever.
Second, once the projectile exits the barrel we have a rocket like effect of gasses exiting the barrel pushing back. Again no way "resistance" can come into it.
Third, the momentum of the burnt and unburnt powder being propelled forward has to be matched by the gun going backwards. Also no relation to rifling.
The only actual difference in recoil when shooting a rifle vs smoothbore is the angular component. When the projectile starts being spinned up by the rifling the gun acquires the same twisting momentum at opposite direction. Basically we have the rifle trying to be rotated by recoil somewhat. I've noticed this, but overall I don't think this effect is responsible for the existence of the myth of lower recoiling smoothbore.
Am I mistaken about this? Am I missing something? I'm surprised that seemingly wrong statements from 19th century books are repeated verbatim in various places without being challenged. Finally, if "classics" are wrong about this, what else they are wrong about?
I would be very interested to find out what others think about it.
| DarylS |
| (.700 member) |
| 06/09/19 03:45 AM |
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Re: On subject of smoothbore vs rifled felt recoil
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There are a few inconsistencies in Forsyth's book as pertaining to ballistics as we know them today.
I assume that if there is indeed a difference in recoil between a rifled 14 bore or identical build to a smooth 14 bore, both with identical patching and ball weight, it would most likely be unnoticeable to the shooter.
Another "Book" claim re: velocities:
We have tested the claims of higher velocity with a smooth bore with a given charge against a rifle of the same size, with the same length of barrel and charge. The results were within normal shot to shot variation.
| Heelerau |
| (.300 member) |
| 07/09/19 07:48 AM |
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Re: On subject of smoothbore vs rifled felt recoil
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I have noticed for years that there is less recoil from a rifle or smooth bore shooting ball than rifle shooting a conical bullet. Eg my enfield Pat 58 has more recoil than a .62 smoothbore both shooting service charges. The smooth bore is in fact a heavier charge.
| DarylS |
| (.700 member) |
| 07/09/19 10:53 AM |
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Re: On subject of smoothbore vs rifled felt recoil
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Ball weight is so much the deciding factor.
At most, a .62 smoothie will be shooting a 300gr. ball, while the Enfield carried a 560gr.(I think) Pritchert "conical ball".
| 3DogMike |
| (.400 member) |
| 08/09/19 11:10 AM |
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Re: On subject of smoothbore vs rifled felt recoil
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Just my experience only, and for what it is worth:
Some years ago I had a W.W. Greener 8bore brass case gun (rifle) that was smoothbore in the right tube and fully rifled in the left tube.
I could not discern one bit of difference in recoil ........ this was with period 10Dram BP loads and bore/groove size round balls.
- Mike
| Sarg |
| (.400 member) |
| 08/09/19 10:29 PM |
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Re: On subject of smoothbore vs rifled felt recoil
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That is very interesting & a good firearm to judge the recoil effect I’d say ?
Do you have any photos ?
Sounds like a cool rifle/gun , I did many years back see a Greener like that & it was a hammerless as I remember !
| 3DogMike |
| (.400 member) |
| 08/09/19 11:34 PM |
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Re: On subject of smoothbore vs rifled felt recoil
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Quote:
That is very interesting & a good firearm to judge the recoil effect I’d say ?
Do you have any photos ?
Sounds like a cool rifle/gun , I did many years back see a Greener like that & it was a hammerless as I remember !
Hello Sarg,
Photos? Well that was long enough ago that any pics were using a real film camera.....I will have to sort thru old photos to see.
Yes, the Greener was a hammerless action as well. Never did contact Greener to get historical info, more’s the pity.
Quite the spectacular display if it was fired at twilight.....looked like a Roman Candle going off.
I imagine that if one were hunting in dry brush with such a cannon that there would be a high probability of starting a wild fire.
- Mike
| Sarg |
| (.400 member) |
| 09/09/19 11:03 PM |
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Re: On subject of smoothbore vs rifled felt recoil
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Hello Mike, be great if you found those photos, I had some on my computer of the other or maybe your old Greener 8 bore before I had a computer melt down !
It was a cool old girl !
| szihn |
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| 14/09/19 01:47 AM |
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Re: On subject of smoothbore vs rifled felt recoil
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I make and restore muzzleloaders to earn about 90% of my living and I have a few decades of experience. I also have been a barrel maker in the past and so I have some experience in both the making of barrels and the loading and shooting of them
So here are the facts:
The faster the twist is in a barrel the more resistance it is going to create between the forward movements of the ball or bullet in relation to it's powder charge.
If the rifling is very slow the difference is very slight, but you can feel some difference between two guns of the same weight with one having a twist of about 1 in 40" to one that has a very long twist,(say 1-96") or no rifling at all.
HOWEVER as a rule, smooth bore guns were made with lighter barrels.
Making a gun of the same bore diameter as another that you compare it to, but with one gun weighing a noticeable amount less is ALWAYS going to make the light gun kick more if the ball weight and powder charge is the same in both.
So the scientific fact that a rifled gun is going to develop more recoil is usually off-set by the fact that in most cases, 2 guns of the same bore size will show that the smooth bored gun is lighter.
In a smoothbore you need no extra wall thickness to cut grooves into, but also, the styling of smooth bores (Fowlers for the most part) was different then rifles in the old days so in the real world, given 2 guns of equal bore, the rifle kicks less, not more, if the power charge and projectile weight is the same in each.
In many cases the power charge of a rifle is greater then it is in a smooth bore, so the real world often shows that any rifle that kicks harder then a smooth bore is because of heavier projectile weight and/or powder charge, not so much the fact it's rifled.
| DarylS |
| (.700 member) |
| 14/09/19 02:45 AM |
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Re: On subject of smoothbore vs rifled felt recoil
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The only test we actually did on a similar subject was for and velocity differences between rifled and smooth.
The "premise" from the 1860's book, stated that a smoothbore gun will deliver higher velocity per charge, than the same bore size gun with rifling.
Our tests showed virtually identical velocities with the same powder charges and ball.
A 20 bore smooth bored gun and .62 calibre rifle were used in the test. The rifled gun needed much thicker patching to use the smooth bored gun's ball,
of course, yet the velocity difference between them, was within variations of shot to shot velocity spreads - less than 20fps, certainly nothing meaningful.
NitroX
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| 14/09/19 11:10 AM |
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Re: On subject of smoothbore vs rifled felt recoil
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Simple physics. Rifling means more friction going forward. Means more force backwards ie recoil.
| 3DogMike |
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| 19/09/19 12:36 PM |
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Re: On subject of smoothbore vs rifled felt recoil
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Quote:
Simple physics. Rifling means more friction going forward. Means more force backwards ie recoil.
??? Friction could certainly raise pressures.....
I'm only an aviator and not a ballistician, but I'm not so sure about friction & "more force backwards ie: recoil", something about Newton's Third law and all that?
Besides, once the rilling is engraved and the ball is rotating I'm thinking friction would be the same as smoothbore "if" one is talking about a lead projectile obturating to fill the bore
Yes-No?
- Mike
| DarylS |
| (.700 member) |
| 20/09/19 05:05 AM |
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Re: On subject of smoothbore vs rifled felt recoil
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Forsyth spoke of rifling as being a hill the ball or bullet had to climb, thus increasing recoil and reducing velocity over a smoothbore of identical gauge.
We tried the test as I noted above, but the subjective recoil test phase was not possible due to different ergonomics & weight of the 20 bore guns used. There was literally no difference in velocity. Thus, from the test, we felt recoil was most likely similar as well- but not tested.
I think Mike's 8 bore would have given a more accurate representation on both aspects & should be believed. It is the perfect test vehicle.
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NitroX
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| (.700 member) |
| 20/09/19 11:35 AM |
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Re: On subject of smoothbore vs rifled felt recoil
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Quote:
Forsyth spoke of rifling as being a hill the ball or bullet had to climb, thus increasing recoil and reducing velocity over a smoothbore of identical gauge.
Yes it is simple physics.
| DarylS |
| (.700 member) |
| 21/09/19 02:45 AM |
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Re: On subject of smoothbore vs rifled felt recoil
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Yes it is, but how much actual, measurable difference first of
all and secondly, will it be noticeable - that's the key question?