Interesting for someone that methodical to think it is good to have the shots leave at the top of the vibration cycle. It is not.
2025 100 yard .22LR discussion thread
- Thread starter grauhanen
- Start date
If the bullet leaves at the same point that's consistency, so really doesn't matter where it 'leaves' IMO.
I haven't read the whole thread for some time so I don't recall what post you're referring to. Just my thought on your post.
I haven't read the whole thread for some time so I don't recall what post you're referring to. Just my thought on your post.
I’ve shot that same rifle but with factory stock. It’s the 2nd most accurate 22LR I’ve ever handled. And with inexpensive ammo (Blazer 40gr Grey box). I also was impressed with the general build quality on it, aside from some odd machining of some tiny aspects.
And here I am passing mapleseed. Not only did I pass on all 3 attempts, I was also the only person attending who passed. AFAIR my worst score was 225/250. Im also only wearing a $25 Crappy tire sweater. Too bad i didn't get some Sitka - imagine how much I'd know then!
Guess what I used?
a $199 chinese rifle with a $199 Vortex chinese scope shooting CCI SV in a Home Hardware PINE stock that I rattle canned a week before the event. It was still off-gassing the day of the event. Every animal I gotten was shot through the heart while being offhand - last one was 180 yards.
Im not good at a lot of things, but I have a natural knack for marksmenship, calf raises, sarcasm, and putting people like you in your place
Of course, that's just my opinion. (which you didnt understand the first time)
Good shooting!
While there isn't unanimity about how tuners work, this is not an unusual view when it comes to explaining how tuners do their "thing".
The idea is that muzzle movement is elliptical. The timing of the shot should be so that it exits at a point in time where the muzzle movement slows and stops ever so briefly for a millisecond. This apparently occurs at the top of the oscillation movement.
grauhanen, You beat me to it, I'm running a load of laundry. I believe Shorty was referring to Post 70 on the Stowaway posts. Yes, the 'top' of the flex would have a slight 'delay' , as would the bottom, too. I don't have a tuner but I'd guess there is a pretty good 'tuner adj' at 2-points to account for the Top and Bottom of the flex.
If the barrel is always in the same position when the shot leaves then on target you will see vertical dispersion that precisely matches the variation in muzzle velocity. The post I'm referring to is the one you just shared on accurateshooter. Stowaway shared an animation showing barrel movement and shots leaving at the top of a sine wave representing a node in its movement cycle.
Many people having an incorrect view doesn't make their incorrect view correct. This is a very simple physics problem, and the physics dictates that you will get the best results, the least amount of vertical, when the shots leave during a barrel upswing, not when it is near static. As we've already discussed at great length on previous occasions, including sharing the math with you multiple times, including earlier in this thread where I gave you the math for a few distances.
The fact that tons of shooters think you'll get the best results if shots leave when the barrel comes to a node in its movement cycle doesn't mean they are correct. Lots of people thinking something doesn't make that something correct. You need more than consensus based on nothing. You also need theory and evidence. And there's a ton of evidence holding up the theory of physics. And the "stopped muzzle" theory isn't supported by physics. The "stopped muzzle" theory directly violates physics. It can therefore be discarded as being incorrect. The positive compensation theory relies on physics to work. Failing to understand anything involved in that is not reason for it to be discarded. If one understands everything involved with that theory it is difficult to come to any other conclusion than "This is what is actually happening." And that understanding is also what dispels the "stopped muzzle" theory.
As I said with my 10-metre-diameter barrel illustration earlier, if the barrel cannot move at all you will get vertical POIs that directly relate to muzzle velocity. That 10-metre-diameter barrel idea is no different than the "stopped muzzle" idea. Both involve the barrel being in the same position as shots leave. And both would result in vertical at the target being directly related to muzzle velocity. With positive compensation you can have two shots with differing muzzle velocities go through the same hole because they have differing launch angles. With the insanely large barrel or the stopped muzzle theory you cannot have two shots with different muzzle velocities go through the same hole because they have the same launch angles. And when you have the same launch angles the POI is directly tied to the muzzle velocity. A higher velocity will hit higher and a lower velocity will hit lower. You cannot have a 1050 fps shot and a 1085 fps shot go through the same hole with the insanely large barrel or the stopped muzzle. Physics dictates that to be an impossibility. There's no question about it. There's no discussion. There's no debate. Physics literally says that cannot happen in those circumstances. It is physically impossible. The only way for a 1050 fps shot and a 1085 fps shot to go through the same hole is if their launch angles differ by a certain amount. And back on page 2 in post #26 I showed the calculations that show what those launch angles are for 50 yards, and 100 yards, and 200 yards. Those differences in launch angle cease to exist in the case of the insanely large barrel or the case of the stopped muzzle. And that then means that those two shots will no longer go through the same hole. They instead will hit the target with quite different elevations due to their differing velocities. The fact that many people have trouble understanding that doesn't change that. It is still true even if someone doesn't understand it. The laws of physics still need to be obeyed even if someone doesn't understand physics.
That would be the second worst way to have a tuner adjusted and would result in horrible vertical on target directly tied to muzzle velocity. The only way to adjust a tuner in a worse manner would be to have bullets leaving during a downswing of the barrel so that it amplified the vertical from muzzle velocity. You need shots to leave during an upswing of the barrel in order to cancel out the differences in vertical due to differences in muzzle velocity.
This is always true. It's why they remain incorrect. Correct or not, however, the point was that, in a world where there's no consensus on how tuners do what they do, the idea referred to was not unusual among the many who try to explain tuners.
_______________________________________
For the general reader, the majority of shooters who use tuners probably don't understand how they work. They are satisfied to believe that using them will somehow shrink their groups or score better on target. Most of these shooters will also believe that tuners can achieve more than is physically possible, such as reducing groups by 25 - 50%, which is far more than the 5 -10% that is realistic -- with very good ammo and a correct setting.
Positive compensation (PC) is real. It is the best explanation for understanding how tuners work. For those who are not familiar, it is the idea that rounds with different MVs can be made to have a very similar POI at the distance for which the tuner is adjusted. Of course there are limits to what PC can achieve. For example, PC only works on vertical dispersion and rounds with wide differences in MV between rounds can't be compensated for with a tuner.
Positive compensation does have implications for tuner utility when shooting at varying distances with the same setting. After all, if a tuner shrinks groups due to positive compensation, it works for one distance only. In other words, the same setting can't work at all distances .22LR is used.
Of course if tuners do in fact work at various distances without readjustment then something else in addition to, or instead of, positive compensation may well be involved. This is a question that's been raised from time to time on this forum.
A further note on horizontal dispersion. They do have some effect on horizontal dispersion, but it isn't an intended behaviour, as we are not concerned with that side of things. The mere act of adding some mass to the muzzle tends to bias dispersion in the vertical direction due to gravity and the added mass preloading the barrel downwards. And that preloading downwards biases the start of barrel movement in the upwards direction once the firing cycle begins. When fiddling around with a tuner you usually do see locations in the adjustment range that do have an effect on horizontal dispersion, but we tend to ignore that since we're concerned with what's happening in the vertical. The tuner is slowing things down overall, so it should have an effect on both horizontal and vertical, but we only tune to attempt to remove as much vertical as possible since that should be the dominant dimension.
Great post
Good shooting for your "New Eyes" ! ! I was amazed when I saw what "Black and White" REALLY was vs the 'Beige and White' I had grown accustomed to. Just a thought - when I got my eyes 'done' I found that I'm more comfortable with sunglasses even on overcast days. I use 'over-the glasses' sun-glass goggles because I've found 'Costco Readers' help seeing the fine crosshairs on my Athlon 8-34x56 . . . even after eyepiece focusing.
While I can read the finest line at they eye doctors with zero prescription, the eyes are definitely more sensitive to light; but still needing extra light and +2.25 readers for fine work, but the my glasses also correct for astigmatism at all distances. I have magnetic polarized shades that fit the glasses, they were bought as a pair. What a wonderful age we live in!!
Congratulations. It's a good and better than average first entry. Those following this Challenge will no doubt be looking forward to the improvements which are sure to come.
Wind flags are indispensable at 100 yards. Unfortunately rounds sometimes go where they do for reasons unrelated to wind or MV.
Thanks but the results are poor for this gun. Partly weather and me not wanting to get wet. It was my first attempt so I posted to track progress. The barrel is a 20” Kukri profile Bartlein. The handle is MDT XRS which I painted. Great bang for the buck imo. Shot the challenge again on Monday. Early in the am before the wind and put up flags this time, although they didn’t move hardly at all. I used a different lot of Lapua Long Range I’ve been squandering. The average was 0.716”! I only compete against myself but after receiving a derogatory PM I’ll share pics of targets but won’t submit any in the challenge. Everything was the same other than weather, ammo and used Jerry’s MPod which on carpet seems to work. Cheers
