Interesting, at least to me.

[garandman]

What puzzles me are spiral lines at the beginning of the MS.

Crazy as it sounds... maybe a slight wobble of the bullet... ???

 

[Capt. Oblivious]

A 308 drops like a waterfall so that explains that...

 

[PigButtons]

As for the swirling lines, plastic under heat and pressure is nearly a liquid. The spin of the bullet, along with the heat of the bullet, and the friction of the high speed of the bullet can be the immediate cause.

 

[pirate ammo]

As for the swirling lines, plastic under heat and pressure is nearly a liquid. The spin of the bullet, along with the heat of the bullet, and the friction of the high speed of the bullet can be the immediate cause.

All true. Air passing over a object at high speed does cause a lot of friction and therefore a lot of heat that alone could cause your problem. Bullet didn't have to touch just be very close.

 

[TAJ45]

Ok, 1) He needs to use the spacer and this would not have happened.


Edit. Gravity does immediately pull on the bullet but the angle on departure nullifies any immediate effect.

Yes he needs a spacer. Said and probably done by now. Hope so anyway.
Angle of departure nullifies nothing.
Is not the bayo fixed to the bbl?
Point the bbl any way you want and the relationship remains the same.

 

[D-4297]

The MS comes with two spacers . One is thicker than the other . If you use the thin spacer on the bottom of the barrel , you can have this occur , or even worse . I made this mistake once , but got away with it , without any damage to the unit . As several have suggested , check the clearance after you have it installed with a rod into the bore . Mine works just fine with approx. a eighth inch clearance below bore line . The thinner spacer can , and almost always will put your bayonet into the bore line / bullet path .

 

[pirate ammo]

The thinner spacer can , and almost always will put your bayonet into the bore line / bullet path .

If your barrel tapers down all the way to the muzzle it could put the end of the bayonet in harms way because it will be at an angle.

 

[jonbearman]

Lesson well learned. Thanks Forum Boss.

 

[Chiquita]

Thank you all for your replies. Lesson is learned.

Last night I attached the bayonet with different spacer combinations and I saw where I could have made the costly mistake.

Now, does anyone have an extra MS bayonet that I can buy.

 

[Sandstorm]

Call MS is my suggestion.....Its a long shot to find one extra, as most
don't carry extra parts they may not require..but hey who knows.

 

[Oso]

I don't think it is a bullet strike, but rather just really close proximity to bore and the polished line is the blast of hot gas and powder remnants.

There are even some better pictures in the following thread that I believe exactly depict what you are seeing as bullet passes over the Magneto.
https://www.snipershide.com/shooting/threads/new-magnetospeed-mounting-option.6889446/

I spent very little time with a Magneto because of the straps, which I could never get to tighten down completely. Although it would give good readings of velocity, I was concerned that it would be at expense of shot groups during load development. It could/would introduce random POI as the bayonet shifted or bounced unpredictably from shot to shot. This was really an issue on some thinner barrels with more pronounced tapers. I replaced it with a Labradar, before some of these mounting solutions were available.

There are several solutions for securing the Magneto bayonet to eliminate any potential impact on barrel harmonics. Do a Goggle Search "Magnetospeed mounting options" and you find some of the popular options from nicely engineered to DIY. Most involve securing it to the stock via a bipod attachment/picatinny rail.

 

[Bc'z]

FWIW, I run the thin spacer, sensitivity set to normal. I always pull bolt and sight the bore to check if I have clearance. I recheck position of bayonet after 3 shots.
I'll run thick spacer when I'm testing a rifle with a brake, and adjust sensitivity to high.
I only run the Chronograph for finalizing load and drop charts.

 

[Tokay444]

I run my Magnetospeed with decent gap and sensitivity set to 6, using an MK Machining mount.