Definitely don’t want to zero with a magnetospeed!

[Swordslayer1]

I'm curious about the stock attachment you mentioned. I was not aware of one. Can you help me out and tell me what to look for and how it works?

 

[Swordslayer1]

I'll send you a message

I use the MK Machining Magnetospeed Rail mount. I don't see a POI change

 

[HEAL]

It's a geometry thing fellas. You ever see the pressure wave coming off the tip of a bullet in high speed photography? What do you suppose happens if the bayonet is close enough to the bullet's path to reflect that wave back into the bullet? Try this....put the bayonet on top of the barrel and tell me where your bullet goes. Longer, slower bullets catch that reflection more readily of course. Geometry.

JUST AN IDEA IT COULD BE TO HAVE A DUMMY BAYONET ALONG ON THE OPPOSITE SIDE TO COMPENSATE FOR THE SAID DEFLECTION. ALL THOSE THAT USE A MS COULD EXPERIMENT WITH AN ATTACHEMENT LIKE THIS AND PUT HERE THE RESULTS. THANKS.

 

[birdiemc]

It's a geometry thing fellas. You ever see the pressure wave coming off the tip of a bullet in high speed photography? What do you suppose happens if the bayonet is close enough to the bullet's path to reflect that wave back into the bullet? Try this....put the bayonet on top of the barrel and tell me where your bullet goes. Longer, slower bullets catch that reflection more readily of course. Geometry.

I read lots of forums about the MS before buying one, and found lots of folks saying the same thing, it deflects opposite of the bayonet

 

[Mram10us]

Love the chrono, just don't want to zero with it on.

 

[lgwatson]

Went out and load tested today at 300yards. Decided on the last group of 4 to test the speed. Threw on the magnetospeed for the first shot. Took it off for the next 3. Here is the target:

View attachment 165809

Guess which shot had the chrono attached?

My magnetospeed makes causes my group to be about 1 1/2" high at 100 yds.

 

[Bingoc]

Went out and load tested today at 300yards. Decided on the last group of 4 to test the speed. Threw on the magnetospeed for the first shot. Took it off for the next 3. Here is the target:

View attachment 165809

Guess which shot had the chrono attached?

Thanks for showing the results. Now I don't have to experiment for myself. Another reason that this forum is so informative to most of us.

 

[Tommo64]

Magnetospeed will defo shift your POI.

 

[Bobhunts]

I would think anything attached to a barrel will change the POI! But the instrument being used is not involved in ones shooting form or the POI! Only to show the speed at which you are sending a bullet. Having said that I think it is fine to use one to just check your speed and then you can go back to working your loads for accuracy!

 

[Impulsive]

I usually work up a load and then use the MS to get the ES, SD, and velocity. I also keep the muzzle the same distance from the end of the mount and the bayonet level across the bottom on all my rifles.
It will still change point of impact a bit, but not more then 1- 1-1/2", usually up and left. I have even had it tighten groups up considerably , just like s tuner.
I don't think it was designed for zeroing.

 

[Mram10us]

Makes me wonder if I were to adjust the tightness of the bayonet if it would tune if differently???

 

[blackbrush1]

Then why do some say it doesn't change their poi and other do? If it is basic geometry, shouldn't it be the same regardless of barrel size? Bullet types would vary.

Variables that affect POI are velocity, bullet length and bayonet proximity to muzzle and bore centerline. Change any one of these enough and you get a different result. Group size variation has more to do with attachment to the barrel and harmonics.

 

[Mram10us]

Variables that affect POI are velocity, bullet length and bayonet proximity to muzzle and bore centerline. Change any one of these enough and you get a different result. Group size variation has more to do with attachment to the barrel and harmonics.

I understand that, but I was referring to the idea that it deflects the path up. That's why I was asking why do some see a change and others don't, if it affects the path upwards.

 

[Jeffrey Van Zandt]

I'm curious about the stock attachment you mentioned. I was not aware of one. Can you help me out and tell me what to look for and how it works?

go to MPA web site and there are others out there

I'm curious about the stock attachment you mentioned. I was not aware of one. Can you help me out and tell me what to look for and how it works?

https://masterpiecearms.com/cat/mpa-ba-accessories/rat-system-accessories/