chronograph vs magnetospeed

[Nomad47]

So has anyone worked a load up using Magnetospeed for days and then shoot load without it? Does the load hold and just have an increase in POI?

There are three combinations. 1. Work up load with MS on, then shoot without MS on as you suggested. 2. Work up load without MS then shoot with it on. Why? 3. Work up load and shoot with it on.
I have done 1 and 3. Last year, I worked up my loads with the bayo strapped on then did ALL my shooting with it on. NO problems whatsoever. And that accounts for why I have 502 strings shot with the bayo attached.
With my new Pierce action with 30" 1.250" straight pipe (no taper), I worked up the load without the MS attached. Then attached MS to check velocity. Bugholes both ways with the POI with bayo attached 1/8" to 1/4" higher.

 

[Bogusname]

Magneto speed. Stop wasting time and holding up the range. Chroneys are relatively inexpensive but the odds are you will eventually shoot it. Then have to buy another. I have the old ms. Still works great. You can probably get a used one cheap.

 

[hogpatrol]

Used the original MS on these firearms with zero change in accuracy and group size but POI would move higher from 1/2 inch to 1&1/2 inches wholly dependent on caliber. The muzzleloader moved the most. Recently purchased the latest model and have noticed the same anomalies.

AR-15 16" milspec barrel .223
AR-15 22" heavy barrel .223
AR-15-22" heavy barrel .20 Practical
Rem 700 26" heavy varmint .20 practical
Rem 700 24" heavy varmint 6BR
Stiller Tac 300 24" Sendero 6.5x284
Rem 700 24" Sendero 6-6.5x47 Lapua
Rem 700 24" #3 fluted 6.5x47
Rem 700 24" Sendero .17 Fireball
Rem 700 18" Featherweight .17 Fireball
Rem 700 24" Sendero fluted .223 match chamber

Anschutz MPR .17HMR
Anschuz Sporter .17HMR
Anschutz 17P pistol .17HMR
Anschutz Exemplar .22 LR
Anschutz Sporter .17HM2
CZ 453 20" varmint fluted .17HMR
CZ 452 .17HM2
Savage smokeless muzzleloader, Pac-Nor 24" .45cal

FD: I have no financial interest in Magnetospeed.
Hog

 

[Chuckhunter]

I have had an Oeher33 since the early 80's and it has performed flawlessly. My friend had the Model 35P and it did the same. Only drawback is setup time. Bought a MS last December and absolutly love it. POI moves up approx 2 bullet holes when attached. Group size does not change. Two weeks ago my display unit on th MS would not turn off when the cable was disconnected from the unit. Contacted MS by Email on a Sunday, recieved instructions to return unit by noon on Monday, I shipped unit on Tuesday and by Saturday of the same week I had a brand new display unit, no charge, covered under warranty. Kudos to MagnetoSpeed for their outstanding service. No one wants to have a problem but in the event that you do, it's good to know their service is excellent.

 

[jfseaman]

Used the original MS on these firearms with zero change in accuracy and group size but POI would move higher from 1/2 inch to 1&1/2 inches wholly dependent on caliber. The muzzleloader moved the most. Recently purchased the latest model and have noticed the same anomalies.
...
Hog

POI shift: Yes, there will be a POI shift. There is a muzzle blast against the bayo. Physics is physics.
Groups size: Yes it will have an effect on group size. There is a damper on the end of the barrel. Physics is physics.

Improvement in group size: Yes, I experienced that with a 270 Weatherby Accumark. Worked up a nice fast safe load that was nicely sub MOA. Took the bayo off and it all fell apart. Worked backward until we found the accuracy again. Plenty fast enough.
Degradation in group size: Yes, I have experienced that with many of the rifles. After the knowledge gained from the 270 Weatherby work up, I now work the load for accuracy then get the numbers. Then take it to the desired ZERO range, then go long range to adjust BC.

I broke 1 bayo with the original strapping system. They fixed it. I now have a V1b bayo and a V2 bayo.

Well over 1000 rounds in many rifles, single shot pistols and a couple revolvers. Hand gun and air rifles are mostly still the relm of the optical chronographs like my Ohler and Chrony.

 

[daniel brothers]

I heard that you are suppose to work up the load with the bayo on... then take it off when adjusting bullet seating depth.

 

[normmatzen]

There is the old anecdotal evidence again! I heard that, or by brother's friend said or some such "evidence."

I have a Magnetospeed as does my friend in Australia. We both tune loads with it on and find no difference with it off. Incidently, we both use tuners too and are trying, with not much success, to find out the actual function of a tuner, We are both engineers and strive to find the exact reason something works.

1. Change in POI
This is simple Physics. The sensors in the BAYO are a pair of small inductors that have a DC current flowing through them. This current generates a small inductive field around the inductor. When the metal bullet pierces that field, it creates a force on the bullet proportional to the bullets mass, speed and intensity of the inductive force. This is an Eddy Effect!
This force imparts an effect on the bullet's flight similar to a small puff od wind from the bottom that causes both my 105gr 6mm and 162gr 7mm bullets to rise about 0.8MOA. I don't worry about this as it is again similar to a consistent wind and I just change my aim point.
2. Change in load tuning.
Again, I don't have the full answer, but I believe from my sparse knowledge of tuners that the MagnetoSpeed is both very light which changes the effective weight of the tuner VERY little. Also the BAYO is flimsy compared to the stiffness of the barrel and when the barrel moves, the BAYO simply wobbles a bit and is not well coupled to the barrel. In addition the BAYO uses rubber pads which further isolate the BAYO from the barrel. In any case, we have not seen a remarkable change in tuning with or without the BAYO attached.

 

[snakepit]

I think another thing that affects the path of the bullet is the shock wave of the bullet as it exits the barrel and hits the air. If you have ever seen a high speed video of a bullet in flight you can see this shock wave which is 360 degrees around the bullet. When this shock wave encounters the Magnetospeed bayonet it can cause the bullet to very slightly deviate from its path. When a aircraft is landing it encounters what is called ground effect where the air that is under the wing and the wing tip vortices compress over the runway as the aircraft is landing and this helps to reduce the rate of descent just prior to touch down and can help to make a smoother landing.

 

[searcher]

If only using the chrono in your "back yard" and not on a range with other folks behing the firing line that are a pain to work around when setting up/taking down your unitd- go for the chrony. About 1/3 the cost of the strap-on and yes, you can even shoot it and still be ahead of the game. I've had mine about 30 years and only shot the diffuser rods (about $10.00 once). If, however, you ever find yourself behing a public firing line, and that is the only place you can use it, you WILL appreciate the strap-on at 3x price. I'd not buy it to do the same thing as the Chrony unless you need it (or don't mind dropping another few bills).