In Defense of Magnetospeed - A Compendium to Set the Story Straight

[Lapua40X]

I've owned a couple of Magnetospeed chronographs; even blew one up and rebuilt it. So I know and understand the product very well. I get upset when I read comments about the product from those who think they know what it is, how it works and how to use it, but do not. The greatest misinformation I see deals with the influence it has over groups on target. Usually something like "it can't be used to test loads for velocity and accuracy simultaneously". Well, truth is that if you can handle a bit of simple mathematics when evaluating impacts on target that type of statement is, IMO, irresponsible (or worse).
So I did some testing at the range this morning to demonstrate the folly of such notions.
My rifle was set for a 100 yard zero. I shot three rounds at the orange circle target to validate that it was properly on target. Subsequently, I mounted my Magnetospeed on the rifle and moved to an adjacent target and fired ten rounds. (I hope you all will forgive me for the 7 o'clock booboo. Just a cheek weld error on my part.)
I hope the naysayers will observe that, aside from the fact that the ten round group is about 1.5 moa above my aim point at the horizontal center line of the target, the group has suffered no adversity - the integrity of accuracy remains intact.

 

[rockable]

I have shot good groups with mine , as well. I just have to adjust about 3 moa of elevation in to compensate on my Savage varmints. I have had trouble with it reading reliably on 40 grain bulet's in my Swift, but that is understandable. Otherwise, no complaints from me.

 

[eric n]

What's a 10 round group look like with it off?
I got tired of testing it, my results are different. Can't say I know why but I get horizontal.

 

[BenPerfected]

In testing with one of my RF guns, the MagnetoSpeed actually measurably improved accuracy....likely the additional weight. It did move the POI.

 

[Quickoz]

I think it will be different for every barrel. It moves PoI for me but I dont use it for group teating but times I have the rifle does shoot well too. But I dont use it when verifying accuracy.

 

[Doug Beach]

I've used mine on two sling guns. Both Barnards with medium Palma barrels. One a .308, the other a 6br. I get a 4moa elevation change (shoots higher w/ it attached). Groups are the same size or smaller. I have fired a 200-17x at 300, and a 200-14x at 600, with the chrono attached. I put it on, adjust my elevation, and go.

 

[eric n]

Top is without magneto, bottom is with it attached. The group with magneto is a little larger then usual but reflects the norm for my testing.
Maybe I'm slightly out of tune, different barrel length, or magneto not attached in the sweet spot. I just can't seem to get it to work.
I'm glad it works for you, sure wished it did for me. It is very convenient and I will get another one. (Hope the pos that stole it shoots it off)

 

[boltfluter]

I've owned a couple of Magnetospeed chronographs; even blew one up and rebuilt it. So I know and understand the product very well. I get upset when I read comments about the product from those who think they know what it is, how it works and how to use it, but do not. The greatest misinformation I see deals with the influence it has over groups on target. Usually something like "it can't be used to test loads for velocity and accuracy simultaneously". Well, truth is that if you can handle a bit of simple mathematics when evaluating impacts on target that type of statement is, IMO, irresponsible (or worse).
So I did some testing at the range this morning to demonstrate the folly of such notions.
My rifle was set for a 100 yard zero. I shot three rounds at the orange circle target to validate that it was properly on target. Subsequently, I mounted my Magnetospeed on the rifle and moved to an adjacent target and fired ten rounds. (I hope you all will forgive me for the 7 o'clock booboo. Just a cheek weld error on my part.)
I hope the naysayers will observe that, aside from the fact that the ten round group is about 1.5 moa above my aim point at the horizontal center line of the target, the group has suffered no adversity - the integrity of accuracy remains intact.

View attachment 983913 View attachment 983914

How do your results really prove anything? The fact that your point of impact does move proves that it is effecting the harmonics of the barrel. In your case it does not seem to effect your group size. In my opinion, you cannot make a blanket statement that all rifles will respond like your rifle barrel has. In essence anything attached to the muzzle will act like a tuner of sorts.

Regards, Paul

www.boltfluting.com

 

[Lapua40X]

What's a 10 round group look like with it off?
I got tired of testing it, my results are different. Can't say I know why but I get horizontal.

It looks just like the 3 round group, just a bit larger. I'm still not good enough to put 'em all into one hole.

 

[bigngreen]

Rotate the bayo a quarter of a turn and shoot a group and watch where it goes.

 

[Lapua40X]

...In my opinion, you cannot make a blanket statement that all rifles will respond like your rifle barrel has. In essence anything attached to the muzzle will act like a tuner of sorts.

Regards, Paul

www.boltfluting.com

Point well taken, Paul. I guess me remarks did take on the appearance of a blanket statement. But that was unintentional. I agree that you cannot be assured that tying something onto the end of the barrel (regardless of how light it might be) will not affect the barrel harmonics. The change in elevation alone testifies to that. Furthermore, as pointed out by others, I too develop the initial load with the chrono off of the barrel and only install it when the load prints well and I want to validate the velocity. That, IMO, is the proper way to use the chrono. But to make debasing remarks about the utility of the product because, at least for some rifles, you can't do both things at the same time (this remark also offered commonly as a blanket statement) is not entirely true. I used a 26 inch Bartlein 1:9 Palma contour .284 for this demo. Thanks for the contribution to the discussion.

 

[JamesnTN]

I've proven it changes group size. Here's an example shot at 500 yards from my 284 Shehane.

This is without the MS

Now here's same load same sitting but with the MS on the barrel

If you want to see real results do the test out at 500-600 yards and you'll see it does make a difference.

 

[chkunz]

The data you have presented is not statistically sufficient for proof. You say this is just an example and that is ok, but please provide more information on the rest of the data that this example represents. Statistically this is important to know if there is enough data to make a conclusion with reasonable statistical probability.

 

[Milo 2.0]

I've proven it changes group size. Here's an example shot at 500 yards from my 284 Shehane.

This is without the MS

Now here's same load same sitting but with the MS on the barrel

If you want to see real results do the test out at 500-600 yards and you'll see it does make a difference.

IMO, you had a flier, group size woulda been almost identical had you put the left one in with the rest.

 

[JamesnTN]

IMO, you had a flier, group size woulda been almost identical had you put the left one in with the rest.

Look at the different shape of the groups take away the flyer you mentioned and see the vertical where as the other group was nice and round

 

[DaveTooley]

James

I wish I had that much confidence in my wind reading, gun handling and reloading skills. It looks like you have a very accurate rifle though.

 

[bigngreen]

I beleive the POI change is gas reflecting of the bayo not harmonics, I've seen groups rotate around with the direction of the bayo, if rotated up the groups went low, rotated right groups go left.

 

[Eric Leonard]

I trust the groups with the MS attached I just do not trust the zero,,

 

[Tommie]

Changing mass will have an effect on barrel harmonics. If group size remains the same and POI doesn't change then it's an extremely lucky set of circumstances. But there's no rule that adding mass will cause things to go south. The added mass could improve grouping. But change of some sort is the most likely outcome.

 

[chkunz]

I beleive the POI change is gas reflecting of the bayo not harmonics, I've seen groups rotate around with the direction of the bayo, if rotated up the groups went low, rotated right groups go left.

Where is the bullet when the gas is being deflected off the bayo?