I’ve just started .69 round balls from a smooth bore. It just seems to happens to be the same charge as I’ve been shooting in my .45-70 lever gun with a 500gn bollit. Both with FF BP. The.45-70 has a lot more recoil. I was wondering why. Is it because tho 45-70 has a better seal ? Not too much difference in gun weight. Any ideas?
My guess is that there is more room in the 69 M/L for the powder to burn and it is not restricted by the crimped in boolit.
swamp
There is no problem so great, that it cannot be solved by the proper application of high explosives.
If the .45-70 boolit is heaver, it'll recoil a bit more to push it out the barrel at approx. the same speed.
Also, the friction from the longer bearing surface will tend to have a bit more resistance/recoil.
In school: We learn lessons, and are given tests.
In life: We are given tests, and learn lessons.
OK People. Enough of this idle chit-chat.
This ain't your Grandma's sewing circle.
EVERYONE!
Back to your oars. The Captain wants to waterski.
if I used calculators correctly the musket would have 2.3X the bore volume per length. so that would lower pressure alot
My guess would be the weight of rifles is different. Stock design will be different also and stock and butt plate shape will greatly effect perceived recoil. The RB in pure lead should be around 460 grains with pure. I have never owned a 69 cal but I cast for a friend that has several. Since it's a smooth bore the bullet doesn't need to as soft. He supplies his own lead. They are under under 450 grains.
Pressure on it's own doesn't effect recoil. The acceleration curve does. The 45/70 will seal better but the RD has more surface area so I don't have a clue which one will accelerate faster.
Last edited by M-Tecs; 06-22-2019 at 11:56 PM.
2nd Amendment of the U.S. Constitution. - "A well regulated Militia, being necessary to the security of a free State, the right of the people to keep and bear Arms, shall not be infringed."
"Before you argue with someone, ask yourself, is that person even mentally mature enough to grasp the concept of different perspectives? Because if not, there’s absolutely no point."
– Amber Veal
"The Highest form of ignorance is when your reject something you don't know anything about".
- Wayne Dyer
.69 round balls achieve only about 850 fps with a 70 grain load of FFg in my muskets. A 500 grain ,45-70 slug will get about 1250 fps with the same load so will naturally have more recoil if the guns are the same weight.
Up that .69 musket charge to 100 grains and then compare.
There are only three factors in the force of recoil. Projectile weight, projectile speed, and firearm weight. Powder is counted as projectile, and being as both are the same, either your velocity is lower on the 69 caliber (quite likely), gun weighs more, or both. "Felt recoil" is a whole other ball game, mostly used by advertising departments. When it comes to felt recoil, the recoil pad, stock shape, balance, everything plays a part in it.
Originally Posted by GregLaROCHE
The difference in felt recoil, beyond stock drop/design, is that the rifling resists the passage of the projectile more than a smoothbore does.
As Sir Isaac Newton once proved: "for every action, there is an equal & opposite reaction".
.
Now I lay me down to sleep
A gun beside me is what I keep
If I awake, and you're inside
The coroner's van is your next ride
Unless the rifling slows or speeds up the bullet vs a smooth bore, it does not effect recoil at all.
Pressure doesn't directly create recoil. A theoretical example would be if the bullet was locked in the cartridge. When the cartridge is fired it would just be a pressurized vessel with zero recoil generated. The reaction to the pressurization is the stress placed on the containment vessel and some heat generated by the pressure. Just like a high pressure SCUBA tank. On the opposite end of the spectrum would be a magnetic rail gun. No pressure created like a firearm but recoil is calculated exactly the same.
The acceleration (speed) of the ejectorate (mass of the projectile and mass of the powder) creates the recoil. The recoil (force) you feel is mass times acceleration. Pressure plays a part in how fast you can push the bullet out of the barrel and the acceleration curve , but it's still the acceleration and mass that is used to calculate recoil. The mass of the firearm does effect felt recoil. The firearm accelerates in the oposite direction (recoil) of the ejectorate.
Increasing friction will normally slow the ejectorate thus decreasing recoil. An example would be a form of rifling or friction that reduce velocity by half. Pressure would be much greater, however, recoil would be significantly less due to the slower ejectrate. The claim that the great pressure pushing back on the cartridge head overlooks the fact that even though the pressure is greater it is solely an internal stress.
Last edited by M-Tecs; 06-24-2019 at 11:10 PM.
2nd Amendment of the U.S. Constitution. - "A well regulated Militia, being necessary to the security of a free State, the right of the people to keep and bear Arms, shall not be infringed."
"Before you argue with someone, ask yourself, is that person even mentally mature enough to grasp the concept of different perspectives? Because if not, there’s absolutely no point."
– Amber Veal
"The Highest form of ignorance is when your reject something you don't know anything about".
- Wayne Dyer
wouldn't hitting rifling from behind push the gun forward ?!?
also I still think, looking at it as a rocket, which I guess a gun is a rocket of sorts with a clog in the exhaust. that the smaller bore would generate a higher specific impulse and hence more recoil all else being equal.
mostly I think were not getting anywhere, especially when mass and velocity values are floating
Yes, it's no different than the mass of the powder hitting a muzzle break.
For the rocket motors orifice size determines the velocity of the ejectorate
http://www.jacobsrocketry.com/rocketry_overview.htm
"There is one more component actually in the rocket motor and that is the combustion chamber but in this simplest version, the combustion chamber is the void area in the center of the propellant. To produce usable thrust, the pressure inside the motor must be higher than the outside atmospheric pressure (considerably higher). The higher pressure inside forces the products of the burning propellant out through a small opening (the nozzle) at a high velocity. The thrust of the engine is dependent on how much mass is ejected out the nozzle in a given time and the velocity. The velocity is dependent on the pressure inside the case and the diameter of the nozzle throat. How much mass is ejected is dependent on the burning area and the burn rate of the propellant. The burn rate depends on the specifics of the propellant such as the chemicals in the mix, the ratios of the chemicals and the particle sizes used to make the propellant plus the pressure. The burn rate of rocket propellants increases as pressure increases. The burning area is controlled by the shape of the propellant. As you can see, even in the simplest rocket motor, there are a number of interacting specifics going on that a rocket motor designer has to keep in mind and figure into the design."
https://www.sciencelearn.org.nz/reso...t-acceleration
Last edited by M-Tecs; 06-24-2019 at 11:27 PM.
2nd Amendment of the U.S. Constitution. - "A well regulated Militia, being necessary to the security of a free State, the right of the people to keep and bear Arms, shall not be infringed."
"Before you argue with someone, ask yourself, is that person even mentally mature enough to grasp the concept of different perspectives? Because if not, there’s absolutely no point."
– Amber Veal
"The Highest form of ignorance is when your reject something you don't know anything about".
- Wayne Dyer
No, rifling has no effect on recoil unless it effects the velocity. M-Tecs is correct in that the pressure curve is considered to effect the so called felt recoil. I have my doubts anyone is that sensitive.
As for actual calculated recoil, no. It is calculated by projectile weight, projectile velocity, and firearm weight. Technically its initial velocity and final velocity, but all bullets obviously start at zero. Those variables calculate both recoil force and recoil velocity.
A muzzle brake is a whole different principle.
so thought experiment.
what if a rifle had a barrel shaped like a U where it starts off firing toward you then makes the corner on your shoulder and heads straight away from you.
what variables of recoil aren't cancelled out from happening in both directions.
And the butt plate
I started out with nothing and I still have most of it left.
Paralyzed Veterans of America
Looking for a Hensly &Gibbs #258 any thing from a two cavity to a 10cavityI found a new one from a member here
@SSGOldfart, that is felt recoil, not really recoil at all. Just what you feel.
@bmortell, that level of physics is beyond me, but I do know that a barrel bent in a U shape and fired recoils forward. I learned this from a Mythbusters episode. I believe this has more to do with momentum than it does recoil.
Yep for felt recoil it's makes a notable difference. I own a Marlin Guide Gun, a Browning 1886 carbine and a Browning 1886 rifle. All in 45/70. The 86 rifle has a crescent butt plate and it brutal with anything over mild loads. The carbine has a flatter wider butt plate it's better than the crescent but it's still a steel butt plate. The Marlin has a recoil pad. The Marlin in the lightest of the three but felt reoil is the least. The 86 rifle is the heaviest but the crescent butt plate magnifies felt recoil greatly.
Last edited by M-Tecs; 06-25-2019 at 12:27 AM.
2nd Amendment of the U.S. Constitution. - "A well regulated Militia, being necessary to the security of a free State, the right of the people to keep and bear Arms, shall not be infringed."
"Before you argue with someone, ask yourself, is that person even mentally mature enough to grasp the concept of different perspectives? Because if not, there’s absolutely no point."
– Amber Veal
"The Highest form of ignorance is when your reject something you don't know anything about".
- Wayne Dyer
Posting Permissions
| BP | Bronze Point | IMR | Improved Military Rifle | PTD | Pointed |
| BR | Bench Rest | M | Magnum | RN | Round Nose |
| BT | Boat Tail | PL | Power-Lokt | SP | Soft Point |
| C | Compressed Charge | PR | Primer | SPCL | Soft Point "Core-Lokt" |
| HP | Hollow Point | PSPCL | Pointed Soft Point "Core Lokt" | C.O.L. | Cartridge Overall Length |
| PSP | Pointed Soft Point | Spz | Spitzer Point | SBT | Spitzer Boat Tail |
| LRN | Lead Round Nose | LWC | Lead Wad Cutter | LSWC | Lead Semi Wad Cutter |
| GC | Gas Check |
Reply With Quote
