Sight in help with M29
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Good shooting partner
Sent from my SM-N986U using Tapatalk
Sent from my SM-N986U using Tapatalk
POI
You can expect the WC rounds to print higher (POI) on the target than the JHP's due to slightly longer barrel time during recoil.
I like my guns to print a little high so the gun isn't covering my POI!
Nice target!
You can expect the WC rounds to print higher (POI) on the target than the JHP's due to slightly longer barrel time during recoil.
I like my guns to print a little high so the gun isn't covering my POI!
Nice target!
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Maybe someone can explain something to me---explain----with easily documented proof------"due to slightly longer barrel time during recoil".
I interpret that to mean the recoil causes the gun to move before the bullet is long gone. I don't believe that.
Many thanks!!
Ralph Tremaine
OP
cjcutter1
Member
This is shot @15yards I adjusted elevation two full revolutions it did come up windage was lookin decent so I left alone I'm no ballistics guy at all ammo was running low that's 38 shots recoil was probably taking effect after awhile so I left it at that yes not ideal but will bullet rise more due to my closerange? BTW I'm a six o'clock hold guy.
Mr. Tremaine
For those of us that shoot our 44s at a distance much farther than the OP did, this phenomenon(simple physics) becomes apparent on every yardage change. The effect is more apparent using heavier bullets, large powder charge, and longer barrels! Physics states " for every action there is an equal and opposite reaction". When the powder ignites and the bullet starts to move there is an opposite, and equal, force exerted on the recoil shield of the revolver, commonly referred to as recoil! Recoil tries to force the gun rearward but the shooter resists forcing the gun upperwards! The amount of recoil is dependent on the weight of the bullet, powder charge, and length of time the bullet spends in the barrel! In my 10 5/8" 44 mag with a 240gr bullet, 23.5grs of H110, and changing the yardage from 25yds to 50yds the RISE of POI is probably 12"-18" but at 100yds the hit is on! With the same 100yd shot the first 25yd shot will not be on a 24x24 square paper!
jcelect
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This!
In real life I've shot a zillion rounds of pistol ammo in precision and action pistol competition and this is true!
On a recent range trip with a recent purchase of a 5" 629 I was shooting 225 grain LSWC's at around 850 fps! With the rear sight screwed down as far as it would go POI was 4 inches high at 25 yards! In order to get POI to POA I had to boost the velocity up to 1050fps!
This is real life!
's
In real life I've shot a zillion rounds of pistol ammo in precision and action pistol competition and this is true!
On a recent range trip with a recent purchase of a 5" 629 I was shooting 225 grain LSWC's at around 850 fps! With the rear sight screwed down as far as it would go POI was 4 inches high at 25 yards! In order to get POI to POA I had to boost the velocity up to 1050fps!
This is real life!
'sMaybe someone can explain something to me---explain----with easily documented proof------"due to slightly longer barrel time during recoil".
I interpret that to mean the recoil causes the gun to move before the bullet is long gone. I don't believe that.
/QUOTE]
While it does not move far while the bullet is in the barrel(about .050"), the gun starts to move as soon as the bullet starts to move ( Newton's Second Law of Motion)and receives all the momentum that you will subsequently feel as recoil. You can't trust your senses, because all this happens before you brain knows the gun has fired.
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In real life I've shot a zillion rounds of pistol ammo in precision and action pistol competition and this is true!
On a recent range trip with a recent purchase of a 5" 629 I was shooting 225 grain LSWC's at around 850 fps! With the rear sight screwed down as far as it would go POI was 4 inches high at 25 yards! In order to get POI to POA I had to boost the velocity up to 1050fps!
This is real life!
I'm no marksman but I've always shot 357 mag more accurately than 38 special. I've always thought it was because, due to the higher velocity of the 357, the bullet left the barrel before I had a chance to screw up. Maybe I was right.
THIS statement explains why only you can sight in your handgun! Each shooters resistance to recoil is different and it gets worse the farther out you shoot!
jcelect
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It seems like the same folks who came up with this equal and opposite business also had something to say about acceleration---so time becomes a factor---as does mass. Those of you who say the gun moves before the bullet's gone seem to be saying the force moves pounds (whatever the weight of the gun) within the same time span as it moved the grains (whatever the weight of the bullet). Right about now is when I say, HUH?!!
I reckon there's a fairly simple mathematical formula to demonstrate this sort of thing, but I don't know what it is.
Ralph Tremaine
I reckon there's a fairly simple mathematical formula to demonstrate this sort of thing, but I don't know what it is.
Ralph Tremaine
Newton's Second Law Of Motion - Derivation, Applications, Solved Examples
Sir Isaac Newton PRS (25 December 1642 – 20 March 1727 )
Defining Newton's Second Law of Motion
Newton's second law states that the acceleration of an object depends upon two variables – the net force acting on the object and the mass of the object. The acceleration of the body is directly proportional to the net force acting on the body and inversely proportional to the mass of the body. This means that as the force acting upon an object is increased, the acceleration of the object is increased. Likewise, as the mass of an object is increased, the acceleration of the object is decreased.
Acceleration is directly proportional to the net force and inversely proportional to the mass.
Newton's second law can be formally stated as,
The acceleration of an object as produced by a net force is directly proportional to the magnitude of the net force, in the same direction as the net force, and inversely proportional to the mass of the object.
This statement is expressed in equation form as,
a=Fnet/m The above equation can be rearranged to a familiar form as
F=ma Since force is a vector, Newton's second law can be written as
F^ =ma^ The equation shows that the direction of the total acceleration vector points in the same direction as the net force vector.
The expanding gas in the barrel exerts the same force on the gun as on the bullet, in opposite directions. The difference in mass results in ma (bullet) = ma (gun), so the acceleration of the bullet is larger than the acceleration of the gun by the inverse ratio of the masses.
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My wife has way smaller hands,wrists and arms that I. She constantly shoots higher than I do. Most revolvers shoot low for me.
Try this. Take a Ransom rest and fire a variety of loads. The heavier loads will hit higher. Then zero it for a load with the clutch tension really tight, then shoot it with the tension way looser. Impact goes up. I made my own Ransom rest and did some fun experiments. It uses regular Ransom inserts. My clutch disk is from a John Deere fan clutch BTW
You seam to be hung up on the fact that the gun weighs way more than the bullet. Very true, But as you know even 1/100 of an inch of sight on a 6" barreled gun with a 2" frame (8" total radius) means 3/100" every 2ft. So in say, 67 ft thats 100/100 of an inch.
In other words, although the gun is heavy the recoil differences do not have to change the movement very much to have an effect down range.
Try this. Take a Ransom rest and fire a variety of loads. The heavier loads will hit higher. Then zero it for a load with the clutch tension really tight, then shoot it with the tension way looser. Impact goes up. I made my own Ransom rest and did some fun experiments. It uses regular Ransom inserts. My clutch disk is from a John Deere fan clutch BTW
You seam to be hung up on the fact that the gun weighs way more than the bullet. Very true, But as you know even 1/100 of an inch of sight on a 6" barreled gun with a 2" frame (8" total radius) means 3/100" every 2ft. So in say, 67 ft thats 100/100 of an inch.
In other words, although the gun is heavy the recoil differences do not have to change the movement very much to have an effect down range.
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jcs266
Member
Elmer Keith talked about these things in the 1940's n 50's - i grew up reading his books. The man forgot more than 99% of us ever knew about ballistics, etc.
Another phenomenon he talked about that blew me away was "barrel vacuum" in shotguns... i can't even explain it.
Another phenomenon he talked about that blew me away was "barrel vacuum" in shotguns... i can't even explain it.
It's not so much that I'm hung up on the disproportionate weight of the gun and the bullet as that seemed to be a logical explanation for the photographs I've been seeing-------------for years.
The first one was of what appeared to be a Model 94 Winchester---and it was being presented as proof of the hypothesis recoil has no effect on the path of the bullet. The photo shows the front end of the rifle resting on a post---and a fired bullet in the air in front of the muzzle----which was still resting on the post. Subsequent photos over the years show bullets in the air---and no (apparent) movement of the guns--although these later photos were not being presented in support of any hypothesis.
I recall subsequently contacting a firearms engineer (Remington, I think) who confirmed the hypothesis, but clearly didn't want to spend any time discussing it. Perhaps he was busy---or perhaps he supposed I was too damn dumb to understand it. If his explanation had tracked with the presentation up above, he'd have been right on target.
Ralph Tremaine
The first one was of what appeared to be a Model 94 Winchester---and it was being presented as proof of the hypothesis recoil has no effect on the path of the bullet. The photo shows the front end of the rifle resting on a post---and a fired bullet in the air in front of the muzzle----which was still resting on the post. Subsequent photos over the years show bullets in the air---and no (apparent) movement of the guns--although these later photos were not being presented in support of any hypothesis.
I recall subsequently contacting a firearms engineer (Remington, I think) who confirmed the hypothesis, but clearly didn't want to spend any time discussing it. Perhaps he was busy---or perhaps he supposed I was too damn dumb to understand it. If his explanation had tracked with the presentation up above, he'd have been right on target.
Ralph Tremaine
ggibson511960
Member
Simply stated, light loads shoot high at short range, and low at longer range.
Most of the recoil impulse of a handgun is reacted (Newton's Law) by angular acceleration and rotation of the handgun/forearm combination of mass. That's why the muzzle rotates and flips up more than it moves back. At 25 yards a .44 Magnum's extended bore line is about a foot below point of aim, about right for a standard velocity round, but not low enough for light kicking loads that take longer to get the bullet out of the barrel and still rotate the handgun and forearm.
The phenomenon is counterintuitive but real. The effect is less pronounced in handguns launching lighter bullets because the ratio of bullet mass to angular moment of inertia is lower. Lots of rifles shoot varying bullet weights to near same POI. If you could hold the handgun with near infinite stiffness all loads would shoot to the same POI at short range, but we can't. .44's kick too hard.
Most of the recoil impulse of a handgun is reacted (Newton's Law) by angular acceleration and rotation of the handgun/forearm combination of mass. That's why the muzzle rotates and flips up more than it moves back. At 25 yards a .44 Magnum's extended bore line is about a foot below point of aim, about right for a standard velocity round, but not low enough for light kicking loads that take longer to get the bullet out of the barrel and still rotate the handgun and forearm.
The phenomenon is counterintuitive but real. The effect is less pronounced in handguns launching lighter bullets because the ratio of bullet mass to angular moment of inertia is lower. Lots of rifles shoot varying bullet weights to near same POI. If you could hold the handgun with near infinite stiffness all loads would shoot to the same POI at short range, but we can't. .44's kick too hard.
OP
cjcutter1
Member
So bottom line my shooting ain't to bad??? ��
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