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Get or give advice on equipment, reloading and other technical issues.

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KHGS
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Re: Groups

Post by KHGS »

AlanF wrote:Dave,

If you are not seeing a change in tune by adding or removing the Magnetospeed, it would imply that making minor adjustments to a conventional rotating tuner wouldn't affect that barrel either? Because in affect a tuner adjustment is adding weight to one position on the barrel and removing same from another.

Alan


I think it is all about the weight & location of the tuner in relation to barrel stiffness (size & weight). The bayo of the Magnetospeed is quite light & if located on the barrel muzzle tightly & in the correct place it has little effect on tune & poi when it is mounted on the heavy barrels used in F Open. I believe that heavy barrels require more tuner weight to tune than light (Palma) barrels. There are other factors (theories) to consider too!!!! :)
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Norm
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Re: Groups

Post by Norm »

Will the Magneto Bayo effect your barrel? I think its just something you have to try on your particular barrel.
Give it a try with and without the Bayo and you will soon know.
Playing with the projectile clearance and Bayo mounting position may also change things. I run with a fair bit of clearance and the thing still reads ok. This may be the reason why I see less effect than others?
I also use non slip rubber to secure the straps so that they do not move under recoil. This is especially important with the big bangers.
AlanF
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Re: Groups

Post by AlanF »

Norm wrote:Will the Magneto Bayo effect your barrel? I think its just something you have to try on your particular barrel.
...

I think you're right. You could be lucky or unlucky.
pjifl
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Re: Groups

Post by pjifl »

I just do not see any degradation in grouping when using a Magnetospeed and have shot 17 X's out of 20 with one on a barrel. Also have seen others do something similar. Maybe with light barrels you will see a difference.

What I do believe is important is a good method of fixing to the barrel. Or at least making sure the original fixing method is tight.
It is not uncommon to see them loosening after a few shots and moving.

Being rather dissatisfied with the system as supplied, I have developed a quite superior system.
Originally, this was to get around large barrel weights with a specially shaped Bayo, but I am now convinced it eliminates one source of error and makes for more consistent barrel vibration and grouping.

A warning. It is patented......

About 4 wraps of tensioned Duct Tape.

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BATattack
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Re: Groups

Post by BATattack »

I have thought that maybe the reason it doesn't have a huge impact on accuracy is because the rubber mounts and soft strap reduce the amount of vibration transfer between the barrel and magneto speed and vise versa. If the magneto speed was ridged mounted with hard plastic or steel clamps it might have more influence on tuning.
AlanF
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Re: Groups

Post by AlanF »

pjifl wrote:I just do not see any degradation in grouping when using a Magnetospeed and have shot 17 X's out of 20 with one on a barrel. Also have seen others do something similar. Maybe with light barrels you will see a difference.

What I do believe is important is a good method of fixing to the barrel. Or at least making sure the original fixing method is tight.
It is not uncommon to see them loosening after a few shots and moving.

Being rather dissatisfied with the system as supplied, I have developed a quite superior system.
Originally, this was to get around large barrel weights with a specially shaped Bayo, but I am now convinced it eliminates one source of error and makes for more consistent barrel vibration and grouping.

A warning. It is patented......

About 4 wraps of tensioned Duct Tape.

Peter Smith.

Good, I'll try about 5 wraps so as not to infringe the patent :D .

I had actually toyed with the idea of leaving the bayo on the barrel (without cable connected) for competition shooting. For purposes of the rules, it would just be a barrel weight, albeit an elaborate one.
AlanF
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Re: Groups

Post by AlanF »

BATattack wrote:I have thought that maybe the reason it doesn't have a huge impact on accuracy is because the rubber mounts and soft strap reduce the amount of vibration transfer between the barrel and magneto speed and vise versa. If the magneto speed was ridged mounted with hard plastic or steel clamps it might have more influence on tuning.

That's a good point Adam.
williada
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Re: Groups

Post by williada »

Guys, consider the tuner test I put below where tiny, tiny amounts influence a tune. This test was done with a variable tuner. A variable tuner works like a lever, the further out the more leverage or it saves adding more fixed weight to a barrel. A weight called a fundamental weight is a fixed weight and yes depending on the barrel profile and weight the right weight can be found to adjust tune. In fact any weight can slow the action of the muzzle. My variable tuner was made based on the fundamental weight, but its adjustment capability gives more flexibility in tuning.

I feel Norm’s Magnetospeed acts like a fundamental weight and by chance you can stumble onto a fundamental weight that suits a tune.

The point some miss, and its evident from the tuner test below, that tunes follow an arc and its the position of your tune group on that arc which will determine that rifle’s compensation profile. So it follows irrespective of group size the rifle will be better or worse at different distances.

Comments have been made there’s only a bit in the elevation differences. I can assure you if you are getting spreads around a minute the bullseye is going to be tickled rather than the X and you won’t be able to absorb subtle wind changes.

Image
DenisA
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Re: Groups

Post by DenisA »

AlanF wrote:
I had actually toyed with the idea of leaving the bayo on the barrel (without cable connected) for competition shooting. For purposes of the rules, it would just be a barrel weight, albeit an elaborate one.


I had thought of this too Alan and just to eliminate the POI difference that may be a result of the bayo, why not mount it back to front in the same mounting position so the bayo doesn't come forward of the crown. Provided theres enough room that it wont recoil in to the front rest.

I haven't done it because I've also found that it doesn't effect group size but does push the group up to 1moa high.
pjifl
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Re: Groups

Post by pjifl »

I think it would breach the rules using one during a high level competition if you can observe velocities because this could allow you to better interpret high and low shots. But I see nothing wrong as long as the shooter cannot see the readout of V after each shot.

Best to tee it up with the RO and other shooters first.


Peter Smith.
bsouthernau
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Re: Groups

Post by bsouthernau »

pjifl wrote:I think it would breach the rules using one during a high level competition



It might be considered to be in breach of 14.1.5 and/or 20.47 although taken in context both of these are referring to WIND measuring devices. I won't be trying it out. :)

Barry
Brad Y
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Re: Groups

Post by Brad Y »

AlanF wrote:
I had actually toyed with the idea of leaving the bayo on the barrel (without cable connected) for competition shooting. For purposes of the rules, it would just be a barrel weight, albeit an elaborate one.


That would have to be one heck of a long gun case!
AlanF
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Re: Groups

Post by AlanF »

Brad Y wrote:
AlanF wrote:
I had actually toyed with the idea of leaving the bayo on the barrel (without cable connected) for competition shooting. For purposes of the rules, it would just be a barrel weight, albeit an elaborate one.


That would have to be one heck of a long gun case!

Yes, even without it, the muzzle on my 34" Bartlein arrives at the mound well before I do :D .
aaronraad
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Re: Groups

Post by aaronraad »

pjifl wrote:I think it would breach the rules using one during a high level competition if you can observe velocities because this could allow you to better interpret high and low shots. But I see nothing wrong as long as the shooter cannot see the readout of V after each shot.

Best to tee it up with the RO and other shooters first.


Peter Smith.


Can I patent the 6th piece of duct tape over the readout during a shoot?

Can't be any worse than the 'time delay' data available from electronic targets, which I assume is hidden from the user at the time. 'Time delay' certainly makes windage effects simpler to calculate and projectiles with big BC errors easier to identify than just reading a muzzle velocity alone.
Be careful what you aim for, you might hit it! Antipodean Industrial - Home of the G7L projectiles
Norm
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Re: Groups

Post by Norm »

After reading some of the comments here about positioning the Bayo. I did some more testing with my Magneto today and got some interesting results.
Initially I was getting a nice tight velocity spread with the bayo fitted 25mm back from the muzzle, so I tried moving the bayo forward to level with the muzzle as some others have mentioned. Immediately I got a step change in my velocity readings.
Basically with the Bayo level with the end of the muzzle I get around 30fps faster readings than if the bayo is 25mm back from the muzzle.
I found this to be repeatable in the two positions I tried. Moving the bayo back and forward resulted in a similar step change in velocity. I never tried other positions so maybe someone else might like to give that a go.
Given this I think is important to make sure that your bayo does not move on the barrel under recoil if you want to get good data on ES and SD. The absolute velocity of your readings however may not be exact depending on where you mount the bayo fitting.
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