Does recoil amount and velocity affect muzzle velocity?

[Bravo 4]

Why don't you build (or maybe someone on here has one, like this fella...hint hint) a free recoil rail and test it out. You can add various degrees of resistance if you wanted to see if that makes any difference and test it against a solid stop with no rearward movement. I too am curious about the barrel mounted chronies that move with the rifle's recoil, you could even test that theory as well against a stationary tripod mounted unit. There are all kinds of possibilities or hypotheses that can be tested.

 

[Clark]

Why don't you build (or maybe someone on here has one, like this fella...hint hint) a free recoil rail and test it out..

It is such a simple problem for Newton's third law, that it is not worth testing.

I was in honors physics under Lowel Brown before he wrote his book on quantum mechanic field theory. He was really anti gun, and all simple physics problems involved guns back then in 1974.

Now physicists explain these problems with baseballs.

 

[Bravo 4]

It is such a simple problem for Newton's third law, that it is not worth testing.

I was in honors physics under Lowel Brown before he wrote his book on quantum mechanic field theory. He was really anti gun, and all simple physics problems involved guns back then in 1974.

I disagree, if he is anti gun then maybe he isn't as smart as some may believe...I kid of course.

 

[Clark]

That old liberal is still alive
https://en.wikipedia.org/wiki/Lowell_S._Brown

He showed us a left hand cork screw particle in his bubble chamber. His Chinese colleague wanted to call it a "screw off", but Lowell would not let him and thought that was funny.

 

[bigngreen]

Why don't you build (or maybe someone on here has one, like this fella...hint hint) a free recoil rail and test it out. You can add various degrees of resistance if you wanted to see if that makes any difference and test it against a solid stop with no rearward movement. I too am curious about the barrel mounted chronies that move with the rifle's recoil, you could even test that theory as well against a stationary tripod mounted unit. There are all kinds of possibilities or hypotheses that can be tested.

Every 1000 yard bench rest rifle does exactly this, but they are 17+ lbs in a small cal so it's small numbers.
I was apart of a series of chronograph tests, these test weren't for rifle accuracy so when we first started we didn't get into a solid shooting possition, at first it looked like we were having a serious chronograph issue the velocities were so wild but all chronographs were tracking, simply getting prone and firmed up eliminated the velocity swings, quite interesting!!!

 

[Edd]

Every 1000 yard bench rest rifle does exactly this, but they are 17+ lbs in a small cal so it's small numbers.
I was apart of a series of chronograph tests, these test weren't for rifle accuracy so when we first started we didn't get into a solid shooting possition, at first it looked like we were having a serious chronograph issue the velocities were so wild but all chronographs were tracking, simply getting prone and firmed up eliminated the velocity swings, quite interesting!!!

How many fps were the swings and what were the cartridges?

 

[Bravo 4]

bigngreen,
I gotcha on the rail guns, but looking at the video of Terminator products the free recoil pushes the rifle back considerably. That seems to be about as extreme as it could be for the likes of what we (as hunters) would face with comparable rifles, not that the recoil would push us back in measurements of feet. One of my rifles however will give you a good shove to the rear if anything but prone and bipod loaded forward. There it is very manageable. Off an adjustable bench rest or tripod it's quite unpleasant, enough so that most folks are afraid to pull the trigger when it's witnessed.

 

[toddc]

How many fps were the swings and what were the cartridges?

My lightweight Lapua ES went from the 50 fps range to under 15 with a soft to hard hold. I have always built very heavy bench guns to hunt with. This 14lb Lapua was a hybrid walkabout + LR deer rig. The ES was driving me nuts as the load density pointed to low ES. Since my Edges usually weighed in the 40s I shot them free recoil.....doesn't work for ES with a 14lber.

 

[Timber338]

My lightweight Lapua ES went from the 50 fps range to under 15 with a soft to hard hold. I have always built very heavy bench guns to hunt with. This 14lb Lapua was a hybrid walkabout + LR deer rig. The ES was driving me nuts as the load density pointed to low ES. Since my Edges usually weighed in the 40s I shot them free recoil.....doesn't work for ES with a 14lber.

These numbers are right in line with what I see with my lighter hunting rifles.

 

[Wedgy]

Arrow speeds are higher and more consistent when shot from a fixture rather than a human arm holding the bow. Similar idea...I don't know.
Manufacturers use this number for their IBO speeds which are like EPA mileage estimates that you will never get. They also use very light arrows.

 

[ohiohunter]

^ and they will sneak in an extra 1/2" draw length.

For every action there is and equal and opposite reaction.

The launching platform matters, the more solid the more motion forward.

Compare a simple y shaped sling shot to a wrist rocket.

For recoil, the more energy moving forward the more energy pushing back. Factor in all the variables and everything is relative and mostly linear. So the bigger and bad *** your caliber the bigger and bad *** you'd better be to handle it.

 

[Clark]

For recoil, the more energy moving forward the more energy pushing back. Factor in all the variables and everything is relative and mostly linear. So the bigger and bad *** your caliber the bigger and bad *** you'd better be to handle it.

The momentum of the projectile + the momentum of the center of mass of the gas = the momentum of the free recoiling rifle.

The kinetic energy of the projectile + the kinetic energy of the gas does not equal the kinetic energy of the free recoiling rifle

example :
a 30-06 bullet may have 2500 kinetic energy foot pounds
a 30-06 rifle may have 20 kinetic energy foot pounds.

example:
a 30-06 bullet and gas may have a momentum of [.025 pounds][3000 fps] = 75 pounds fps
a 30-06 rifle may have a momentum of [10 pounds ][ 7.5 fps] = 75 pounds fps

The momentum equations look like
M1V1 = M2V2

The energy equations look like
E = 1/2 mv^2

Because the bullet energy speed is squared, it has much more energy than the rifle recoil, but the same momentum.

https://en.wikipedia.org/wiki/Recoil