sporter tuning

[William Colbert]

Being a fairly new competitor I feel I can ask questions that others may not.

Can a sporter be tuned somewhat by rear bag placement and by adjusting the battery stop in or out? Heard about fiddling with the action screws just wondering about this idea. Look forward to hearing your comments!

Thanks,
William

 

[GordonE]

William
Bag placement is important but Tuning is doubtful. Action screw tuning is a joke.
Gordon

 

[linekin]

William, I can't answer your questions but did see something in a couple rifles this year in how they "feel" in the rest.
That cz I was shooting hated free recoil & I found a little pressure on the butt settled it down.
The Cooper had a specific "feel" in the front rest it liked.
So I guess in a way when the rest & bag is set up right it would sure seem like you were tuning. The rifles seems to shoot better when they have "it".
Keith

 

[GordonE]

Keith
Are you confusing TUNING with Gun Control?
Gordon

 

[linekin]

Keith
Are you confusing TUNING with Gun Control?
Gordon

Most likely. There just seemed to be a spot where the rifles would shoot a bit better. Nothing to do with tuning I know but with the "settled " down. I could see where it would seem like you were in a better tune.
But your right. Its control.
Keith

 

[GordonE]

Keith
No Disrespect meant to you. This Tuning thing is an EXCUSE for a poor Gun. You just can't tune Junk. A Sporter is no different than a gun with an adjustable tuner. When it shoots learn how to shoot it. A good Action, Good barrel, Good chamber did i say good chamber. Straight and true to the Groves. Not ligned up with a carpenters level. The Shoulder of the Tennon needs to line up DEAD NUTS with the Bolt Counter Bore. Hope that REBEL WIND BAG IN GEORGIA. With his Internet"SAVVY" Learned something.
Gordon

 

[mwezell]

I'm a firm believer that how the gun moves in the rest is directly related to tune. Think about a couple of things that support this. First is velocity. Shoot over a chrono, both pinning the gun hard and by free recoil method. What do you see?
Second, the gun and/or barrel are forced to vibrate differently, pinned hard vs. free recoiled, as energy is allowed to expel by the guns movement or lack thereof, based on how it's held in the rest.
Take it FWIW, but I've seen enough that I'll stay with this until proven wrong.--Mike

 

[GordonE]

Mike
If you pin the Gun to the rest stop with or without a Chronograph it will shoot higher. Where is Tuning? With the velocity spread in rimfire ammo
it would be hard to have any consistancy.
Gordon

 

[mks]

Gordon,
While I shoot a little 22RF, my experience tuning with rest position relates to CF. Using ladder tests on one rifle, two different front rest positions minimized vertical at 100 and 200 yards, respectively. So with that rifle, I used a different rest location for each yardage at matches. After my tests, 6mmbr ran a story on long range tuning with rest position (that story was rerun recently), so I wasn't the first to have this idea. This is not related to gun handling or consistency, but to the dynamic interaction of the stock with the muzzle angle to improve compensation for a particular yardage. Seems like one could do the same thing with a 22RF by chronographing rounds and correlating elevation on target to muzzle velocity, with the objective of having rounds of a range of velocity strike the target at the same elevation by finding the best rest location. To me, this is in principle as much tuning as moving a muzzle device. Have you ever tried anything like this?

Cheers,
Keith

 

[GordonE]

Keith
When you reload your ammo the seating depth is the same every time. Rimfire varies a lot. Not sure it would show on a chronograph. The weight on the muzzle also changes the length of the barrel.
Gordon

 

[mks]

Gordon,
Perhaps not (seating depth -> muzzle velocity). The theory is that seating depth changes the pressure curve, which should affect both bullet exit time and muzzle velocity. Don't know if anyone has ever actually measured this. The difference might be small compared to variations in powder charge.

Tony Boyer talks about ladder-like tuning with a range of seating depth and powder charge to find the powder charge such that elevation on target is insensitive to seating depth. With 22RF, we can't change powder charge, but we could measure seating depth and purposely test rounds with different seating depth. And vary tuner setting, rest locations, stock weight distribution, etc. until vertical dispersion is minimized. Anything that changes bullet exit time and/or muzzle velocity is subject to tuning the rifle/rest system.

Keith

 

[tim]

Gordon,
Perhaps not (seating depth -> muzzle velocity). The theory is that seating depth changes the pressure curve, which should affect both bullet exit time and muzzle velocity. Don't know if anyone has ever actually measured this. The difference might be small compared to variations in powder charge.

Tony Boyer talks about ladder-like tuning with a range of seating depth and powder charge to find the powder charge such that elevation on target is insensitive to seating depth. With 22RF, we can't change powder charge, but we could measure seating depth and purposely test rounds with different seating depth. And vary tuner setting, rest locations, stock weight distribution, etc. until vertical dispersion is minimized. Anything that changes bullet exit time and/or muzzle velocity is subject to tuning the rifle/rest system.

Keith[/QUOTE

A. You missed why the seating depth/ OAL may be important. It has little to do with tuning.
B. Once your gun is tuned, its tuned.

 

[tim]

I'm a firm believer that how the gun moves in the rest is directly related to tune. Think about a couple of things that support this. First is velocity. Shoot over a chrono, both pinning the gun hard and by free recoil method. What do you see?
Second, the gun and/or barrel are forced to vibrate differently, pinned hard vs. free recoiled, as energy is allowed to expel by the guns movement or lack thereof, based on how it's held in the rest.
Take it FWIW, but I've seen enough that I'll stay with this until proven wrong.--Mike

For what it's worth,pinning a gun is a prime example of a CF technique that's worthless in the RF world. I've never seen, even heard of a top flight shooter doing this and it's something I have always paid attention to.
There's 3 ways to shoot a .22, be it sporter or heavy gun, free recoil, light hold, moderate hold.
Pin it or firmly hold it with shoulder you won't be consistant over the long run IMHO.
One of the great things about IR Sporter shooting is that you will learn volumes about .22 BR gun handling that usually translate well to heavy wguns shot over 2 piece rests.

 

[mks]

A. You missed why the seating depth/ OAL may be important. It has little to do with tuning.
B. Once your gun is tuned, its tuned.

Tim,

A. OK, why do you think seating depth is important?

B. I will have to disagree. Tuning depends not on just the equipment, but also on internal and external ballistics. That is why many shooters adjust their tuners based on temperature.

Cheers,
Keith

 

[tim]

Tim,

A. OK, why do you think seating depth is important?

B. I will have to disagree. Tuning depends not on just the equipment, but also on internal and external ballistics. That is why many shooters adjust their tuners based on temperature.

Cheers,
Keith

Really? Tell me, perhaps, first of all, how exactly that's done on sporters? The best ones shoot day on and day out and they shoot scores every bit as good as heavy guns.

Remember, we have different lots to play with MV, but what happens with different seating depths that MAY impact performance? I've given you two good hints, do a little thinking.

As to many shooters adjusting.....I'd be willing to bet you many many more never touch them. According to the worlds "self proclaimed best Schmid in the world" tune once & done. He might be wrong about a lot, this ain't one of them.

 

[mwezell]

For what it's worth,pinning a gun is a prime example of a CF technique that's worthless in the RF world. I've never seen, even heard of a top flight shooter doing this and it's something I have always paid attention to.
There's 3 ways to shoot a .22, be it sporter or heavy gun, free recoil, light hold, moderate hold.
Pin it or firmly hold it with shoulder you won't be consistant over the long run IMHO.
One of the great things about IR Sporter shooting is that you will learn volumes about .22 BR gun handling that usually translate well to heavy wguns shot over 2 piece rests.

Tim, if you re-read what I posted, I think you'll see that I'm not advocating pinning of the rifle except for chrono readings. My point is velocity does change a small amount depending on how hard the gun is held, or not. Pinning it hard will give slightly higher velocities. At least it does for me and I believe this is basic physics.
My point was that if pinning the gun can change the velocity, is it not fair to assume the barrel will react differently, too? There is less energy being expended during the movement of the rifle, pinned vs. free recoiled. Where does that energy go, in terms of vibration?

 

[mwezell]

Obviously, you strongly agree with him on this. Would you explain why you feel this way. It does not seem to apply to cf. How would the two differ in this regard? Why would we expect an object(gun/barrel/etc.) to respond the same way in different temps and under different load variables?
Thanks in advance!--M

 

[mks]

Really? Tell me, perhaps, first of all, how exactly that's done on sporters? The best ones shoot day on and day out and they shoot scores every bit as good as heavy guns.

Remember, we have different lots to play with MV, but what happens with different seating depths that MAY impact performance? I've given you two good hints, do a little thinking.

As to many shooters adjusting.....I'd be willing to bet you many many more never touch them. According to the worlds "self proclaimed best Schmid in the world" tune once & done. He might be wrong about a lot, this ain't one of them.

Tim,
I don't shoot a sporter, or even know what the rules are. Are you saying that tuners are not allowed? The muzzle is probably the most effective place to put a tuner, but an adjustable weight elsewhere on the rifle might work.

No need to be mysterious, I am honestly interested in why you think seating depth is important.

Sure, I know shooters who don't move their tuners, but I know from my own testing that tune changes. Higher temperature means more pressure, shorter muzzle exit time and higher muzzle velocity. This causes bullets to exit on a different part of the muzzle angle curve, which throws off tune. It makes sense. Nice articles on tuning 22's are here: http://www.geoffrey-kolbe.com/articles/rimfire_accuracy/tuning_a_barrel.htm and http://www.varmintal.com/a22lr.htm

If the "Schmid" is still sticking to that story, then he has painted himself into a corner that he can't get out of. I lost respect for him when he wouldn't have an adult conversation with Varmint Al and the rest of us on this forum a few years ago. It's sad.

Hope you are not offended by this, it is not intended that way. But I know that he has some VERY loyal supporters. Let's keep the conversation on the principles of tuning, shall we?

Keith

 

[Bill B]

Tim,

A. OK, why do you think seating depth is important?

B. I will have to disagree. Tuning depends not on just the equipment, but also on internal and external ballistics. That is why many shooters adjust their tuners based on temperature.

Cheers,
Keith

Hmmm, my 2500X was tuned last Feb up here in NY (meaning friggin' cold), I shot it thru spring summer and fall, from Maine to South Carolina, from the Catskill mountains to coastal SC. Never touched the tuner. It shot consistently well regardless of temp, elevation or humidity. I know the cause of every miss; misjudging the wind or mirage. You know what I would call a shooter that adjusted their tuner based on temperature - clueless.

 

[mwezell]

Hmmm, my 2500X was tuned last Feb up here in NY (meaning figgin' cold), I shot it thru spring summer and fall, from Maine to South Carolina, from the Catskill mountains to coastal SC. Never touched the tuner. It shot consistently well regardless of temp, elevation or humidity. I know the cause of every miss; misjudging the wind or mirage. You know what I would call a shooter that adjusted their tuner based on temperature - clueless.

Were you shooting the same ammo at all times?
I'm sorry you feel that I'm clueless. The method I use has worked well for me, though...and I'm happy that your's works for you.--Mike Ezell