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abintx
09-18-2013, 11:43 PM
I have a Master Alpha Shooting Chrony that's a pain to set up and use, especially when there are other shooters at the range.

This looks easy to use: http://www.youtube.com/watch?v=rwFnrFf6DrU

and apparently compares very favorably with expensive chronographs: http://www.youtube.com/watch?v=MgL9T2ZO2wc&feature=related

Has anyone used one of these?

What did you think of it?

rooshooter
09-19-2013, 05:10 AM
I have most certainly used these and am in no hurry to go back to the old kind. I have used the barrel mounted ones at night time, bright sunshine and in the rain with good testing results.
I only use it to check speeds and don't really get to shoot groups with it, but some say it does affect the zeros and tune, some say it doesn't.

SGJennings
09-19-2013, 09:03 AM
The Magnetospeed is just so handy. Basically, keep it with you all the time and when you want to capture velocity, put it on. No fuss, no muss, no cease fire. Not affected by light conditions, target angle, etc. Very consistent.

Oh, and you can shoot good groups with one on the barrel.

http://i52.photobucket.com/albums/g39/Greg_Jennings/30Major3Shot_zpsdbfac022.jpg (http://s52.photobucket.com/user/Greg_Jennings/media/30Major3Shot_zpsdbfac022.jpg.html)

abintx
09-19-2013, 10:09 AM
I'm only looking for a convenient way to check velocity. This looks like a winning tool. Thanks. :)

John Kielly
09-19-2013, 05:55 PM
I'm emotionally with Francis on this. It's logical on so many fronts. I just wished that I hadn't watched a friend shoot F class with it at 1000 yards with no change to his elevation zero when it was on or off.

Andy Cross
09-19-2013, 07:28 PM
I bought a magnetospeed unit about a year ago. One of the first things I did was check the calibration with a signal pulse generator. Very accurate between 1500fps and 3800fps. Showed about 6% faster when the velocity was under 1500fps and about the same slow reading over 3800fps. Nor was it influenced by lighting, target angle etc. Sold my Oehler and don't miss it.

As far as grouping with it attached to the barrel. Forget it. The BR rifle essentially doubled its group size with it attached. The field rifles which don't shoot as well as the BR rifle did worse.But I don't care. If I am checking velocities I am not trying to shoot tight groups and vice versa
Andy.

HuskerP7M8
09-20-2013, 12:34 AM
Hi Andy,

After checking the accuracy of the unit, did you also try measuring the precision?

Thanks,
Landy

Andy Cross
09-20-2013, 06:57 PM
Hi Andy,

After checking the accuracy of the unit, did you also try measuring the precision?

Thanks,
Landy

I think what you are really asking is whether the shot to shot or in this case pulse to pulse variation varied very much. A couple of feet per second which is about what I would expect with the type of circuits being used. The circuits are not thermally shielded either so these variations could increase and decrease between hot and cold days. Nor did I check it to see how vulnerable it was to interference from such things as mobile phones etc. But for all intents and purposes it is ahead in many respects for convenience and accuracy compared to anything they have come up with in the past.
Andy.

glp
09-21-2013, 10:06 AM
From a dog lover, I hope this fellow doesn't shoot too many center fire rounds with his dog standing near. Good way to make the pooch deaf prematurely. I wonder if there is a life span to the barrel mounted sensor given the intensity of the muzzle blast of a centerfire? Good video and interesting product.

abintx
09-21-2013, 12:20 PM
Purchased the V1 yesterday. They don't seem to be discounted, however I found one at Midway USA for $265. Ten dollars less than the retail price of $275, plus Midway gave me a September discount [till the 25th] of $20. $245 total. Magnetospeed's HQ, incidentally, is here in Austin.

Texas Plinker
09-22-2013, 02:36 AM
I bought a magnetospeed unit about a year ago. One of the first things I did was check the calibration with a signal pulse generator. Very accurate between 1500fps and 3800fps. Showed about 6% faster when the velocity was under 1500fps and about the same slow reading over 3800fps. Nor was it influenced by lighting, target angle etc. Sold my Oehler and don't miss it.

As far as grouping with it attached to the barrel. Forget it. The BR rifle essentially doubled its group size with it attached. The field rifles which don't shoot as well as the BR rifle did worse.But I don't care. If I am checking velocities I am not trying to shoot tight groups and vice versa
Andy.

I have used my MagnetoSpeed numerous times at 600yd with my 6BR and the group sizes have been close to or the same with or without the MagnetoSpeed installed. The POI, point of impact of the group does change but corrections to the scope elevation and windage can correct the group POI.

I am adding to this post the results of a comparison I did several months ago with and without my MagnetoSpeed installed on my 6mm BR/30" barrel. I tested at 600 yds with calm to light right to left crosswinds and some light mirage. All in all the conditions were pretty good. When I returned home I measured the target/groups on my computer using the On Target Precision Calculator Target 2.1 Program. The first 4 shot group without the MagnetoSpeed measured 1.346" wide x .540" tall and the second 4 shot group with the MagnetoSpeed installed measured 1.390" wide x .506" tall. The group with the MagnetoSpeed was 4.281" down and 1.291" left center to center from the group without it. When I shot the second group the right to left crosswind was slightly increasing. I made no sighting corrections for the winds when I shot these groups. When I have done test like this before just resetting the scope will usually correct the group displacement. The group to group displacement also seems to vary according to caliber and loads and also will be smaller at shorter distances. Like I said this test was done at 600yds.

Vibe
09-22-2013, 11:38 AM
Hi Andy,

After checking the accuracy of the unit, did you also try measuring the precision?

Thanks,
Landy
I'm sure that the 6" spacing between the detectors comes into play here. As would the sensor excitation frequency.

Andy Cross
09-22-2013, 06:49 PM
I have used my MagnetoSpeed numerous times at 600yd with my 6BR and the group sizes have been close to or the same with or without the MagnetoSpeed installed. The POI, point of impact of the group does change but corrections to the scope elevation and windage can correct the group POI.

I am adding to this post the results of a comparison I did several months ago with and without my MagnetoSpeed installed on my 6mm BR/30" barrel. I tested at 600 yds with calm to light right to left crosswinds and some light mirage. All in all the conditions were pretty good. When I returned home I measured the target/groups on my computer using the On Target Precision Calculator Target 2.1 Program. The first 4 shot group without the MagnetoSpeed measured 1.346" wide x .540" tall and the second 4 shot group with the MagnetoSpeed installed measured 1.390" wide x .506" tall. The group with the MagnetoSpeed was 4.281" down and 1.291" left center to center from the group without it. When I shot the second group the right to left crosswind was slightly increasing. I made no sighting corrections for the winds when I shot these groups. When I have done test like this before just resetting the scope will usually correct the group displacement. The group to group displacement also seems to vary according to caliber and loads and also will be smaller at shorter distances. Like I said this test was done at 600yds.

It seems odd that something loosely attached to the end of the barrel has no effect on the grouping ability. Virtually every short range BR rifle I saw shoot with one attached essentially doubled the group size at 100 and 200 yards. Not that it really matters as no one tries to shoot tight groups while checking velocities. You are either doing one or the other.
Andy.

Andy Cross
09-22-2013, 06:56 PM
I'm sure that the 6" spacing between the detectors comes into play here. As would the sensor excitation frequency.

Yep the six inch spacing would have been chosen by the designer for a reason. I doubt if they tossed a coin to determine that. But it is a constant. The spacing doesn't vary. The gauss of the magnetic field - which is also a constant - would have been selected for the excitation band widths and amplitudes it would respond to as well as the material the bullet is made from.
Andy.

Texas Plinker
09-22-2013, 09:43 PM
It seems odd that something loosely attached to the end of the barrel has no effect on the grouping ability. Virtually every short range BR rifle I saw shoot with one attached essentially doubled the group size at 100 and 200 yards. Not that it really matters as no one tries to shoot tight groups while checking velocities. You are either doing one or the other.
Andy.

Your statement about "something loosely attached to the end of the barrel" makes me wonder if you were installing the bayonet correctly. The instruction manual says to pull the cinch strap up through the strap adjuster until ALL the slack is taken up around the barrel. Then tighten the Thumb Nut against the Screw Frame until tight. Test the grip of the strap by tugging on the bayonet; if it is unmovable then proceed. If not, continue tightening the Thumb Screw. I know that when I follow the installation instructions my bayonet is extremely tight and unmovable and not "loosely attached to the end of the barrel" as you indicated. If it is "loosely attached" it probably will affect your grouping.

The figures that I gave you are what they are and I have repeated similar groups several times. I know other shooters that have had similar experiences as I have had with the Magetospeed and although I have not, there are some who have shot in competition with it installed.

HuskerP7M8
09-22-2013, 09:58 PM
I think what you are really asking is whether the shot to shot or in this case pulse to pulse variation varied very much. A couple of feet per second which is about what I would expect with the type of circuits being used. The circuits are not thermally shielded either so these variations could increase and decrease between hot and cold days. Nor did I check it to see how vulnerable it was to interference from such things as mobile phones etc. But for all intents and purposes it is ahead in many respects for convenience and accuracy compared to anything they have come up with in the past.
Andy.

Andy,

Thanks and also sorry. My question wasn't concise enough and you had to assume what I was inquiring about.
Here's where I'm coming from and it's probably more info than anyone wants to hear about. LOL

Some time ago (7 or 8 years?), I decided to build a testing facility with tunnel and I wanted to incorporate a dual chronograph system capable of "accurately" measuring MV and "precise" enough to gather ballistic data for calculation of drag coefficients when one of the units was positioned downrange. I wanted to use a chronograph system in conjunction with some very sophisticated analytical software written by an experimental physicist I've worked with for quite some time and a semi-automatic electronic targeting system that would allow me to capture the x,y coordinates on a Cartesian Plane for every single shot I fired.

Anyway, to make a very very long story much shorter, I wrote several lengthy posts on another forum detailing everything I'd done over about a two year period to measure accuracy, precision, and calibrate the two chronographs. It generated a lot of feedback, PM's, and inquiries thru email asking my opinion on various chronograph systems.
In several of those inquiries about the MagnetoSpeed I expressed my concern that the MagnetoSpeed chronograph's sensor distance (as Vibe pointed out) was one of my major concerns, as was the clock speed.

I "think" you've answered my question regarding accuracy and the degree of precision appears to satisfy the demands of most, for a very convenient and very practical method of gathering velocity data. I still have a lot of questions concerning the precision of the unit, but of the dozen or so shooters I've visited with....all seem to be satisfied with the MagnetoSpeed.

Thanks,
Landy

Andy Cross
09-23-2013, 12:20 AM
Your statement about "something loosely attached to the end of the barrel" makes me wonder if you were installing the bayonet correctly. The instruction manual says to pull the cinch strap up through the strap adjuster until ALL the slack is taken up around the barrel. Then tighten the Thumb Nut against the Screw Frame until tight. Test the grip of the strap by tugging on the bayonet; if it is unmovable then proceed. If not, continue tightening the Thumb Screw. I know that when I follow the installation instructions my bayonet is extremely tight and unmovable and not "loosely attached to the end of the barrel" as you indicated. If it is "loosely attached" it probably will affect your grouping.

The figures that I gave you are what they are and I have repeated similar groups several times. I know other shooters that have had similar experiences as I have had with the Magetospeed and although I have not, there are some who have shot in competition with it installed.

You mention cinch strap and thumbscrew. Those terms are contradictory to making an attachment tight and unmovable. Just touch the end of the bayonet lightly with a finger. You can see it move. Which in my opinion is loose. I couldn't get the system any tighter. But as I mentioned it doesn't matter as it won't be shot with it attached anyway.
Andy.

Andy Cross
09-23-2013, 12:29 AM
Andy,

Thanks and also sorry. My question wasn't concise enough and you had to assume what I was inquiring about.
Here's where I'm coming from and it's probably more info than anyone wants to hear about. LOL

Some time ago (7 or 8 years?), I decided to build a testing facility with tunnel and I wanted to incorporate a dual chronograph system capable of "accurately" measuring MV and "precise" enough to gather ballistic data for calculation of drag coefficients when one of the units was positioned downrange. I wanted to use a chronograph system in conjunction with some very sophisticated analytical software written by an experimental physicist I've worked with for quite some time and a semi-automatic electronic targeting system that would allow me to capture the x,y coordinates on a Cartesian Plane for every single shot I fired.

Anyway, to make a very very long story much shorter, I wrote several lengthy posts on another forum detailing everything I'd done over about a two year period to measure accuracy, precision, and calibrate the two chronographs. It generated a lot of feedback, PM's, and inquiries thru email asking my opinion on various chronograph systems.
In several of those inquiries about the MagnetoSpeed I expressed my concern that the MagnetoSpeed chronograph's sensor distance (as Vibe pointed out) was one of my major concerns, as was the clock speed.

I "think" you've answered my question regarding accuracy and the degree of precision appears to satisfy the demands of most, for a very convenient and very practical method of gathering velocity data. I still have a lot of questions concerning the precision of the unit, but of the dozen or so shooters I've visited with....all seem to be satisfied with the MagnetoSpeed.

Thanks,
Landy

When you really have to know what speed an object is travelling at, its rate of acceleration, deceleration, energy losses etc then you have to spend some serious money on systems using broad beam tracking lasers and the like, connected to computers with insane clock speeds. Spending 300K would not be out of the question. But for most of us the consistency produced by the magneto type chrono's should be adequate.
Andy.

Texas Plinker
09-23-2013, 01:46 AM
:D
You mention cinch strap and thumbscrew. Those terms are contradictory to making an attachment tight and unmovable. Just touch the end of the bayonet lightly with a finger. You can see it move. Which in my opinion is loose. I couldn't get the system any tighter. But as I mentioned it doesn't matter as it won't be shot with it attached anyway.
Andy.

Cinch strap and thumbscrew are the terms used by the MagnetoSpeed manufacture in their instruction manual. If you think those terms are contradictory to making an attachment tight and unmovable as they state then maybe you should do all us MagnetoSpeed owners a favor and ask them to correct those terms in their manual.

Then above you said "it won't be shot with it attached anyway" so how will you make it work, hold it in front of the barrel. Just joking.

Andy Cross
09-23-2013, 02:54 AM
Cinch strap and thumbscrew are the terms used by the MagnetoSpeed manufacture in their instruction manual. If you think those terms are contradictory to making an attachment tight and unmovable as they state then maybe you should do all us MagnetoSpeed owners a favor and ask them to correct those terms in their manual.

Then above you said "it won't be shot with it attached anyway" so how will you make it work, hold it in front of the barrel.

I don't believe that magnetospeed had any intentions of making the unit attache tightly enough so that it was considered unmovable. Just tight enough to keep it in place when subjected to muzzle blast and recoil. But when you think about it that's all that's needed isn't it.

Let me clarify the last bit for you. It won't be shot attached to the barrel at any other time other than when you are checking the velocities. Well I wouldn't imagine any shooter thinking otherwise. Would you ? So yes of course I will attache it to the barrel when using it. Hold it up in front of it give me a break.
Andy.

Texas Plinker
09-23-2013, 10:32 AM
Let me clarify the last bit for you. It won't be shot attached to the barrel at any other time other than when you are checking the velocities. Well I wouldn't imagine any shooter thinking otherwise. Would you ? So yes of course I will attache it to the barrel when using it. Hold it up in front of it give me a break.
Andy.
Give me a break, I was just joking with you.

Vibe
09-23-2013, 12:50 PM
Not that it really matters as no one tries to shoot tight groups while checking velocities. You are either doing one or the other.
Andy.

Why wouldn't you want to do both? That's exactly the information you'd need to verify to know how you achieved the accuracy, and what kept you from it. But I do agree, the current mounting system might not be the best route to that.

Texas Plinker
09-23-2013, 01:30 PM
As far as grouping with it attached to the barrel. Forget it. The BR rifle essentially doubled its group size with it attached.
Andy.

I guess part of my problem with your response is your attitude that a good group cannot be achieved with the MagnetoSpeed attached. I am not saying that everyone and every rifle can have good groups with it installed but it is possible and it does happen and by many shooters. SG Jennings post #4 includes pictures of his group with it installed and my post #12 gives the measurements of groups with and without it installed. I guess your comment "Forget it" is pretty conclusive of your opinion on whether it can be done.

dmoran65
09-23-2013, 02:19 PM
Quote Originally Posted by Andy Cross
Not that it really matters as no one tries to shoot tight groups while checking velocities. You are either doing one or the other.
Andy.

I guess I must be an odd duck, because I conduct +90% of all my testing and developments with at least one chronograph in place, and strive by the data's feedback.

Don't even need a chronograph to just check speed. MOA to target from a zero feed into a ballistic program will give very accurately predicted speed without setting any chronograph up or strapping anything on a barrel. And actually more accurate speeds then many chronograph setups will.

Editing in: The above is also a good way to check/calibrate a chronograph to accuracy.

Donovan Moran

Charles E
09-23-2013, 03:25 PM
Why wouldn't you want to do both? That's exactly the information you'd need to verify to know how you achieved the accuracy, and what kept you from it. But I do agree, the current mounting system might not be the best route to that.

Actually, to be precise for tuning, you want bullet time-in-bore. We're just sorta kinda inferring that from MV, but ceteris ain't always paribus.

You'd think with all the cool stuff coming down the pike, we could get a gismo that would tell us that, too. Bet you one of the guys on the board could make one -- Convince Jerry Hensler that he needs it for rimfire & it'd be done in a month or less. Or alinwa, he's another that'll go to the ends of the earth for an answer. Or Vibe, one of the Keiths, PBike, on & on.

dmoran65
09-23-2013, 03:38 PM
Actually, to be precise for tuning, you want bullet time-in-bore. We're just sorta kinda inferring that from MV, but ceteris ain't always paribus.

Strain gauges on a barrel (aka: pressure trace) do just that, in-bore barrel times/exit times.
I have an RSI system myself (bought it in 2006, but should update to the newer wireless units).

Donovan

Vibe
09-23-2013, 05:13 PM
Strain gauges on a barrel (aka: pressure trace) do just that, in-bore barrel times/exit times.
I have an RSI system myself (bought it in 2006, but should update to the newer wireless units).

Donovan
I was thinking the same thing. Particularly since this image was posted on another board recently.
http://varmintal.com/22lr-chamber-pressure.png
I guess if you wanted to be REALLY anal about it, multiple strain gages would also indicate a specific acceleration curve. That particular image refers to rimfires, but the gist is the same.

But a measured muzzle velocity, and a different POI, would naturally indicate a differing "Time in Barrel".

The only additional input would be a Kolbe muzzle angle indicator. :D

Normmatzen
09-25-2013, 05:22 PM
I, too, have a MagnetoSpeed and since getting it, I haven't looked back! Sold the old Chroney!

I use mine on a couple hunting rifles as well as my 6BRX long range bench rest gun.

I, as well as others, have found the point of impact raised about a MOA with the MagnetoSpeed attached. One MOA at the target is a very small angle indeed and my theory is that as the bullet passes over the two inductors and induces a very slight current into the inductors creating a very slight up-kick due to repulsion from inductor to "moving charge" ( the bullet).
In addition, I find that any error caused in barrel tuning is hidden in my skill, or lack of same. I think two factors are at play. I have a tuner on my barrel and 1, the light weight of the Bayo compared to barrel plus tuner makes for a very small error in tuning. 2, If the barrel is tuned precisely the slight tuning error is eliminated by the Q of the tuning. That's why we tune so carefully, so any deviation from perfect load is still within the compensation of the tune. After all, I check my tune by shooting small groups with variations of powder charge of 0.3 gn and tune to smallest vertical. I don't think the light, loosely coupled (rubber MagnetoSpeed mounting pads), create significant error to the actual tune.
I have heard of folks actually competing with the Bayo on the barrel. My friend and mentor in Australia shoots F Class and for practice they have informal "meets" and he competes with it on with no degradation in scores. He, too, has a tuner.

Andy Cross
09-25-2013, 10:25 PM
I, too, have a MagnetoSpeed and since getting it, I haven't looked back! Sold the old Chroney!

I use mine on a couple hunting rifles as well as my 6BRX long range bench rest gun.

I, as well as others, have found the point of impact raised about a MOA with the MagnetoSpeed attached. One MOA at the target is a very small angle indeed and my theory is that as the bullet passes over the two inductors and induces a very slight current into the inductors creating a very slight up-kick due to repulsion from inductor to "moving charge" ( the bullet).
In addition, I find that any error caused in barrel tuning is hidden in my skill, or lack of same. I think two factors are at play. I have a tuner on my barrel and 1, the light weight of the Bayo compared to barrel plus tuner makes for a very small error in tuning. 2, If the barrel is tuned precisely the slight tuning error is eliminated by the Q of the tuning. That's why we tune so carefully, so any deviation from perfect load is still within the compensation of the tune. After all, I check my tune by shooting small groups with variations of powder charge of 0.3 gn and tune to smallest vertical. I don't think the light, loosely coupled (rubber MagnetoSpeed mounting pads), create significant error to the actual tune.
I have heard of folks actually competing with the Bayo on the barrel. My friend and mentor in Australia shoots F Class and for practice they have informal "meets" and he competes with it on with no degradation in scores. He, too, has a tuner.

It's a pity we live on virtually opposite sides of the globe. Otherwise I would get you to shoot your magnetospeed chrono on my PPC with any of the 4 barrels I have for it at the moment. You would find I was not dreaming about the lousy grouping with it attached. At 100 yards in light consistent wind conditions you won't get better than a mid to high .3
Andy.

abintx
09-25-2013, 11:18 PM
I'm all for keeping it simple. Put it on the barrel, capture velocity for two 10 round groups, average each group, average the two averages ... if you want. Take it off the barrel. Record the averages for reference. Then move on to something more important.

SGJennings
09-26-2013, 12:28 AM
Going to have to have one of those RSI wireless pressure trace dealies. That's awesome info.

Andy Cross
09-26-2013, 08:45 AM
I'm all for keeping it simple. Put it on the barrel, capture velocity for two 10 round groups, average each group, average the two averages ... if you want. Take it off the barrel. Record the averages for reference. Then move on to something more important.

I never considered the poorer grouping ability with it attached to the barrel to be important. Just a fact. But the shot to shot variations in velocity, standard variations etc I do consider important. I think this information is as important as many other aspects of precision shooting. Why would one want to just move on. Doing that defeats the purpose of gathering the information in the first place.
Andy.

dmoran65
09-26-2013, 11:26 AM
Hope I don't come across to abrupt here, and am in no way discrediting any brand of chronograph or any individuals uses of them. To each our own......

I have spent a lot of time shooting over chronographs and have had as many as 7 chronographs set inline at one time (while testing chronographs), and can report there is a lot of variances between all chronographs on a whole (even between the same models). Also can report that setup and consistent setup can greatly improve most all brands/models accuracy levels. With dual/triple "eye" sensor types, controlled lighting and/or artificial lighting can greatly improve there accuracy and repeatability. I repeatedly find direct sunlight and certain sunlight angles can be very detrimental to any "eye" censored type, no matter what the brand/model.

What I look for in any chronograph setup, no matter what the brand or price tag, is how well it will pattern or simulate with the actual POI's on the target. Where to say if a bullet prints higher on the target, does the chronograph also say that by the velocity.
If a chronograph setup doesn't target simulate to say at least 75% of the actual POI's on the target, I deem any of the ES, SD, and Average data are in to large of error to be creditable.
In all honesty I want target simulation probability to be 85% or greater before I will look upon any ES, SD, Av, as factual data.

I've been able to get good consistence, repeatability, and target simulation from even the very inexpensive chronographs when a good setup is implemented. But when just setting them out in the element sort to speak, typically the data yields just that.

Infrared lighting I find can greatly improve eyed sensor type chronographs, but still with limitations to direct sun-light. When shaded or in complete darkness, I've really seen high levels of simulation and repeatability from day to day, month to month, year to year, with infrared.
Acoustic setups are the best I've yet to use/see. To bad there wasn't more of them and at cheaper prices!.!.!

In closing and to the OP's topic, if you have a Magnetospeed or any brand, model, type and it will pattern/simulate to above 75% of the time, it is better then many. If it will do +85% or better, then it is a pretty respectable setup, in my opinion/experience.
I don't care what the name brand or how much it costs, if the setup is poor, so will be the FACTUAL data. If we expect "laboratory results", we need to give them a "laboratory setup" and control all the effecting elements we can.

Donovan Moran

abintx
09-26-2013, 11:36 AM
I never considered the poorer grouping ability with it attached to the barrel to be important. Just a fact. But the shot to shot variations in velocity, standard variations etc I do consider important. I think this information is as important as many other aspects of precision shooting. Why would one want to just move on. Doing that defeats the purpose of gathering the information in the first place. Andy.

Andy, I'm a short-range shooter. I'm only interested in seeing that the velocity for my 30BR and 6PPC are within the accuracy norms for the cartridge. For example: 2950-3050 for the 30BR, and 3300-3380 for the 6PPC for the bullet-barrel-powder-brass-primer combo I'm using that's putting bullets through the same hole. Once I'm there, I rather spend my time practicing over a good set of wind flags in varying conditions. I could care less about ES and SD. To me, those numbers have been rendered immaterial by bullets going through the same hole.

I'm a firm believer that you never tune with a chronograph, you tune with the bullet-barrel-powder-brass-primer combo that has bullets going through the same hole. Once you've done that the mission has been accomplished. For me, the numbers associated are for historical reference only.

I believe that what one looks at, is predominately determined by the yardages one shoots at. And, the importance one shooter versus another shooter places on the information gathered, will vary.

Andy Cross
09-26-2013, 06:32 PM
Andy, I'm a short-range shooter. I'm only interested in seeing that the velocity for my 30BR and 6PPC are within the accuracy norms for the cartridge. For example: 2950-3050 for the 30BR, and 3300-3380 for the 6PPC for the bullet-barrel-powder-brass-primer combo I'm using that's putting bullets through the same hole. Once I'm there, I rather spend my time practicing over a good set of wind flags in varying conditions. I could care less about ES and SD. To me, those numbers have been rendered immaterial by bullets going through the same hole.

I'm a firm believer that you never tune with a chronograph, you tune with the bullet-barrel-powder-brass-primer combo that has bullets going through the same hole. Once you've done that the mission has been accomplished. For me, the numbers associated are for historical reference only.

I believe that what one looks at, is predominately determined by the yardages one shoots at. And, the importance one shooter versus another shooter places on the information gathered, will vary.

I agree. But once I have a tune if the rifle stops putting them through the one hole then I go back and check the chrono data to see if it has changed. If not I look for some other issue.
Andy

Normmatzen
09-27-2013, 03:46 PM
When I mentioned that the magnetospeed didn't up set groups, I was talking about long range BR and F Class.
I never said anything about 100 yd BR and the absolutely insane groups you folks shoot!

armabill
09-27-2013, 05:27 PM
Can it detect plain lead bullets?

Andy Cross
09-27-2013, 06:42 PM
Can it detect plain lead bullets?

It can be set via software to detect bullets made from various materials. The sensitivity level can also be altered.
Andy.

armabill
09-28-2013, 08:20 AM
This unit(s) sounds really good.

I can then get rid of my old Chrony. Never did like the way it sets up. My son blew out the screens one time when he set it too close to the muzzle. He learned.

warbird2006
04-12-2015, 04:41 PM
Hey rooshooter.
I agree that it must affect group size and point of impact.
How can you hang something on a barrel and not affect the tune. It may be great to test velocity but I would stop there.

I think so too, it must throuw the barrel harmonics out of the whack.

warbird2006
04-12-2015, 04:50 PM
I guess part of my problem with your response is your attitude that a good group cannot be achieved with the MagnetoSpeed attached. I am not saying that everyone and every rifle can have good groups with it installed but it is possible and it does happen and by many shooters. SG Jennings post #4 includes pictures of his group with it installed and my post #12 gives the measurements of groups with and without it installed. I guess your comment "Forget it" is pretty conclusive of your opinion on whether it can be done.

Well, I use a chrony for my load development mostly, and one thing you don't want, during a load development, is to have anything strapped on the front tip of your barrel.

Wilbur
04-12-2015, 07:33 PM
I suppose the statement that needs to be made is that the affect to one is not always seen on another. If everyone understands that each rifle may be affected differently - then we're good.