Grand Power Xcaliber Vs Tanfo Stock 2

[EngineerEli]

If we're getting into the physics of it, we should consider some actual numbers. Slide (reciprocating mass) weights, barrel weights... Also I would be curious if we could figure out the relative slide velocity between the two. A large part of recoil with lightly sprung comp guns is when the slide hits the rear of movement and contacts the frame, then the dip as it returns to battery.

[valerko]

It's not all just about physics. It all boils down how gun "feels " when fired and who's holding it. Recoil is very subjective

[JRM83]

CZ shoots good. Tanfo shoots good. Grand Power shoots good. Glock shoots good.

There is a lot of speculation, pseudo-science, and actual science about something that just doesn't make all that much difference. Whatever marginal difference in recoil exists between the platforms is negated by shooter skill level.

[Wesquire]

Uh.... my vote of confidence goes to the physics degree.

My few classes in physics, statics, dynamics make me agree much more with him.

Probably felt recoil is mitigated by the rotating machanism taking a longer time, thus reducing the magnitude impulse. At a guess, the rotation probably starts sooner than the unlocking in the cz pattern. Even a few miliseconds here and there can make a felt difference.

Not questioning his physics knowledge, he is just misunderstanding how pistols work.

[Wesquire]

If we're getting into the physics of it, we should consider some actual numbers. Slide (reciprocating mass) weights, barrel weights... Also I would be curious if we could figure out the relative slide velocity between the two. A large part of recoil with lightly sprung comp guns is when the slide hits the rear of movement and contacts the frame, then the dip as it returns to battery.

The slide weights shouldn't change the actual recoil, just the feel. Heavier slides will have longer impulses. That's why I compared it to 115gr vs 147. Longer impulse is usually easier to shoot well on a noncomped gun

[rbebeau]

If we're getting into the physics of it, we should consider some actual numbers. Slide (reciprocating mass) weights, barrel weights... Also I would be curious if we could figure out the relative slide velocity between the two. A large part of recoil with lightly sprung comp guns is when the slide hits the rear of movement and contacts the frame, then the dip as it returns to battery.

Putting in numbers and doing a proper analysis would take years! There is a multi-billion dollar, global industry around making guns that shoot better. Convince CZ & GP to send me their Solid Works simulations and it would be a lot easier.

Uh.... my vote of confidence goes to the physics degree.

My few classes in physics, statics, dynamics make me agree much more with him.

Probably felt recoil is mitigated by the rotating machanism taking a longer time, thus reducing the magnitude impulse. At a guess, the rotation probably starts sooner than the unlocking in the cz pattern. Even a few miliseconds here and there can make a felt difference.

Not questioning his physics knowledge, he is just misunderstanding how pistols work.

I believe I said that the 'upwards force' is a resultant force. That means I collapsed a lot of other forces into one that was equivalent. It's kinda like in a car; The pistons in the engine go up and down - but the wheels have a force backwards.

Now let me be clear. I am arguing that the PHYSICS of rotary barrel work. The 'tilt style' barrels, the 'rotary' barrels, and the weird action that the Walter CCP uses all have sound thinking behind them. Whether one specific gun has less recoil than the other is a matter of the engineering ( the details of the design I outlined earlier ).

[Wesquire]

If we're getting into the physics of it, we should consider some actual numbers. Slide (reciprocating mass) weights, barrel weights... Also I would be curious if we could figure out the relative slide velocity between the two. A large part of recoil with lightly sprung comp guns is when the slide hits the rear of movement and contacts the frame, then the dip as it returns to battery.

Putting in numbers and doing a proper analysis would take years! There is a multi-billion dollar, global industry around making guns that shoot better. Convince CZ & GP to send me their Solid Works simulations and it would be a lot easier.

Uh.... my vote of confidence goes to the physics degree.

My few classes in physics, statics, dynamics make me agree much more with him.

Probably felt recoil is mitigated by the rotating machanism taking a longer time, thus reducing the magnitude impulse. At a guess, the rotation probably starts sooner than the unlocking in the cz pattern. Even a few miliseconds here and there can make a felt difference.

Not questioning his physics knowledge, he is just misunderstanding how pistols work.

I believe I said that the 'upwards force' is a resultant force. That means I collapsed a lot of other forces into one that was equivalent. It's kinda like in a car; The pistons in the engine go up and down - but the wheels have a force backwards.

Now let me be clear. I am arguing that the PHYSICS of rotary barrel work. The 'tilt style' barrels, the 'rotary' barrels, and the weird action that the Walter CCP uses all have sound thinking behind them. Whether one specific gun has less recoil than the other is a matter of the engineering ( the details of the design I outlined earlier ).

Again, you are completely missing how the tilt actually works. It isn't a resultant force. It is no force at all. The barrel simply falls down when the lugs aren't locked. I'm not questioning your knowledge of physics, but you just don't understand how the tilt/rotation are working.

[busdriver02]

You guys are arguing tacks. Bullet and gas goes one direction, gun goes the other direction. Total momentum for both directions is the same. Everything else is a matter of human perception. If the rotating barrel system acts to slightly delay unlock and slide cycling, you'll get a softer shooting but less flat gun. Same concept as a flat bottom firing pin stop on a 1911.

But it still has more recoil than the heavier gun. Conservation of momentum and all.

Edited November 16, 2015 by busdriver02

[Wesquire]

You guys are arguing tacks. Bullet and gas goes one direction, gun goes the other direction. Total momentum for both directions is the same. Everything else is a matter of human perception. If the rotating barrel system acts to slightly delay unlock and slide cycling, you'll get a softer shooting but less flat gun. Same concept as a flat bottom firing pin stop on a 1911.

But it still has more recoil than the heavier gun. Conservation of momentum and all.

That's exactly why I said you really only have to know the total weight and the bore axis to compare recoil and (to an extent) muzzle flip. There's not any other relevant forces going on. The stock 2 indisputably has less recoil than the GP. The GP, having a lighter slide, will be 'snappier' (some consider this "flatter" since the muzzle is flipped for less time). The stock 2 will be softer, and the muzzle will not have the same peak height of flip as the GP. I consider THAT to be flatter.

Basically:

Actual recoil: Stock 2 100%. The physics here are undeniable.

Muzzle flip: GP will 'flip' faster and higher. Stock 2 will flip slower and lower. Overall the Stock 2 will flip with less effect because the weight of the gun 'mutes' more of the momentum than the GP.

Edited November 16, 2015 by Wesquire

[busdriver02]

Momentum=Mass x Velocity. It isn't muting anything. Slide lightening does the opposite of what you think it does. Lighter slide will have more velocity, but when you figure the impulse when it hits the frame you end up with less force. Likewise the lighter slide lowers the CG of the gun.

If I stick to the momentum model... When the slide hits the frame they essentially become one mass. The higher that center of mass above your hand the more it will want to rotate up.

Edited November 16, 2015 by busdriver02

[Wesquire]

Momentum=Mass x Velocity. It isn't muting anything. Slide lightening does the opposite of what you think it does. Lighter slide will have more velocity, but when you figure the impulse when it hits the frame you end up with less force. Likewisr the lighter slide lowers the CG of the gun.

The more weight the gun has, the less velocity it will move at. Thus, it DOES 'mute' the momentum. The mass side of the equation isn't a problem. The velocity is. That is undeniable. Lighter slides do move faster, I haven't said otherwise. I'd like to know why you think it results in less force though. The same momentum is transferred, the lighter slide is just moving faster...which makes the recoil more 'snappy' and less soft.

[busdriver02]

It doesn't really matter when you look at the gun as a whole. As you said, momentum transfer is momentum transfer. But as you drop the slide mass, acceleration change isn't linear. Solve for slide velocity for momentum then plug that into f=ma.

It's really only useful if you're trying to figure out how much the frame is getting beat up.

[busdriver02]

That said, by your own logic if a lighter slide is just transferring the same momentum it shouldn't effect recoil feel at all.

The lighter slide lowers the CG, which makes the gun less "flippy." A lighter gun that has zero muzzle rise tendancy would still hit your hand harder than a heavier gun with zero muzle rise tendancy.

ETA. Phone typing about physics is freaking hard... this part dropped out from the last one. A plastic frame stops the slide a teeny tiny bit slower than steel on steel. That will effect the feel at that moment.

Edited November 17, 2015 by busdriver02

[Wesquire]

That said, by your own logic if a lighter slide is just transferring the same momentum it shouldn't effect recoil feel at all.

The lighter slide lowers the CG, which makes the gun less "flippy." A lighter gun that has zero muzzle rise tendancy would still hit your hand harder than a heavier gun with zero muzle rise tendancy.

ETA. Phone typing about physics is freaking hard... this part dropped out from the last one. A plastic frame stops the slide a teeny tiny bit slower than steel on steel. That will effect the feel at that moment.

It effects the feel of the recoil because the amount of time the slide is moving is different. Spread the same force over a longer time and it will feel softer. That simple. Lower CG has nothing to do with it. Put the same amount of weigh on the magwell as on the dust cover...the dust cover weight will reduce the flip more even though the CG is higher. Funny how Vogel put more weight on the slide of his limited glock. Someone should tell him that causes more muzzle flip. http://automaticaccuracy.net/wp-content/uploads/2014/03/IMG_20140326_141707759.jpg

[ericjhuber]

Uh.... my vote of confidence goes to the physics degree.

My few classes in physics, statics, dynamics make me agree much more with him.

It gets better. He also has a degree in applied mathematics.

[busdriver02]

Go watch a slo mo video of a gun cycling. Theres no real muzzle rise prior to the slide hitting the frame. You don't feel much at all until that point.

As far as Vogel's slide weight contraption, maybe he likes the way it swings? I'm going to go out on a limb and say he doesn't have a problem with recoil control regardless.

Edited November 17, 2015 by busdriver02

[Wesquire]

Go watch a slo mo video of a gun cycling. Theres no real muzzle rise prior to the slide hitting the frame. You don't feel much at all until that point.

As far as Vogel's slide weight contraption, maybe he likes the way it swings? I'm going to go out on a limb and say he doesn't have a problem with recoil control regardless.

Yeah, that's also why Vogel filled the flashlight with lead, not to help recoil. Lol. What's your point about the flip? Obviously the momentum hasn't transfered as much until the slide hits. Edited November 17, 2015 by Wesquire

[busdriver02]

My point is making the slide faster/lighter doesn't make the gun snappier. Making the slide slower/heavier doesn't make it softer. At least not directly as a function of slide speed.

Changing total mass of the gun and moving the center of mass does. It just so happens to be heavily influenced by the slide, since it's the heaviest part. So if someone wanted to add a crap load of weight to a gun, after running out of room on the dust cover the slide might start looking like a decent comprise. Especially if the slide rides decently low to the shooters hand.

Edited November 17, 2015 by busdriver02

[Wesquire]

My point is making the slide faster/lighter doesn't make the gun snappier. Making the slide slower/heavier doesn't make it softer. At least not directly as a function of slide speed.

Changing total mass of the gun and moving the center of mass does. It just so happens to be heavily influenced by the slide, since it's the heaviest part.

I'd like to know your thought process about that. A fast slide and a slow slide are going to transfer their momentums at different speeds. The light slide is snappier. The cycle speed is faster. Same momentum transferred faster = more snappy. It is that simple. The momentum isn't all transferred the instant the slide hits the rear. It is transferring momentum until the recoil spring overcomes the momentum and pulls the slide forward. The heavier slow slide will be at the rear longer, making the impulse spread over more time i.e. Softer.

Here's a video of me shooting my stock 3. I was experimenting with different grip pressures. However, there really wasn't a huge change in flip from shot to shot. That's because it is a heavy ass gun. Shooting my glock or a grand power... the flip is much much more when my grip isn't on point.

https://youtu.be/7X_chtLsU3Q

Edited November 17, 2015 by Wesquire

[busdriver02]

Keep the slo mo pistol video in mind. The recoil spring does very little and actual slide rearward travel time isnt dramatically different across the range of spring weights most people use. In any case the spring seat is usually in line with your hand, so it wont contribute to muzzle rise meaningfully.

Momentum is transferred to the frame (and then shooter) when any delaying mechanism functions (rotating barrel do-dad?maybe, beats me), the hammer cocks(with a well fit flat bottom FPS this acts a little like a lever delay), and the barrel drops out and impacts the frame. The barrel mass is by far the largest of those. Everything else is the slide whacking the frame. Fast slide, slow slide, doesnt matter

The only thing that affects the "rate" that momentum gets transferred is elasticity of the frame material. But it isnt much. Either way, it's not instantaneous, but it's really freaking fast. Fast enough to be modeled as a collision in my opinion.

Which means the momentum of the slide before it hits the frame will equal the momentum of slide and frame together after. Then your hand gets involved, which is where the center of gravity part matters. The further the CG is from your hand (a pivot point) the more it will want to rotate about that point.

We haven't touched on how the mass is distributed around the gun yet! Mass far from the CG will increase "rotational inertia" and make it more resistant to muzzle rise. Full length dust covers, muzzle devices, big ass unobtainium magwells all do this.

Keep in mind when changing the weight of a slide(in either direction), you're changing multiple parameters. And every parameter that changes may not be helpful. Engineering is like that, a soup sandwich of compromises.

Edited November 17, 2015 by busdriver02

[Wesquire]

Keep the slo mo pistol video in mind. The recoil spring does very little and actual slide rearward travel time isnt dramatically different across the range of spring weights most people use. In any case the spring seat is usually in line with your hand, so it wont contribute to muzzle rise meaningfully.

Momentum is transferred to the frame (and then shooter) when any delaying mechanism functions (rotating barrel do-dad?maybe, beats me), the hammer cocks(with a well fit flat bottom FPS this acts a little like a lever delay), and the barrel drops out and impacts the frame. The barrel mass is by far the largest of those. Everything else is the slide whacking the frame. Fast slide, slow slide, doesnt matter

The only thing that affects the "rate" that momentum gets transferred is elasticity of the frame material. But it isnt much. Either way, it's not instantaneous, but it's really freaking fast. Fast enough to be modeled as a collision in my opinion.

Which means the momentum of the slide before it hits the frame will equal the momentum of slide and frame together after. Then your hand gets involved, which is where the center of gravity part matters. The further the CG is from your hand (a pivot point) the more it will want to rotate about that point.

We haven't touched on how the mass is distributed around the gun yet! Mass far from the CG will increase "rotational inertia" and make it more resistant to muzzle rise. Full length dust covers, muzzle devices, big ass unobtainium magwells all do this.

Keep in mind when changing the weight of a slide(in either direction), you're changing multiple parameters. And every parameter that changes may not be helpful. Engineering is like that, a soup sandwich of compromises.

You are completely wrong about the rate of momentum transfer. The slide stays back longer on a heavier slide because it is still transferring momentum. The cycle rate is just a function of how fast the momentum shifts are being transferred. That is "snap". Now, you might prefer the snap, but it is there nonetheless.

[busdriver02]

Sorry, I missed the video.

If it sounds like I'm arguing that a lighter gun will recoil less, that's not my intent. It won't, ever. What I mean is how the shooter perceives that recoil can "feel better." So if all you did was lighten the slide on your pistol, the total velocity due to recoil would increase. The CG would get lower however, so it might feel flatter and easier to call shots; or if you're recoil sensitive, that same mod might make it feel snappy and unpleasant.

If you then added the same weight back to the frame of the gun, it would have less muzzle rise and the same recoil as before.

[Wesquire]

Sorry, I missed the video.

If it sounds like I'm arguing that a lighter gun will recoil less, that's not my intent. It won't, ever. What I mean is how the shooter perceives that recoil can "feel better." So if all you did was lighten the slide on your pistol, the total velocity due to recoil would increase. The CG would get lower however, so it might feel flatter and easier to call shots; or if you're recoil sensitive, that same mod might make it feel snappy and unpleasant.

If you then added the same weight back to the frame of the gun, it would have less muzzle rise and the same recoil as before.

Lighten the slide and it will cycle faster, the momentum transfer will also have a higher peak. It will not be as soft. This may be preferable but not to most.

[busdriver02]

The dwell you see in slo mo videos with the slide aft isn't momentum transfer happening. Thats the slide accelerating from a stand still. The recoil part is well over at that point.

[metalnwood]

I dont know much about the design of pistols, I am just getting in to the sport myself but I know a little about engineering and when I saw the design and read it accounted for less recoil I thought it was based on the simple mechanism on the barrel to turn linear movement in to rotational movement.

Some of the forces that would act to push the pistol back are also rotating the barrel which hits a hard stop.

How much is absorbed I dont know but it must be something.