Home Forums Hunting & Shooting Ask The Gunwriters Magneto speed mounts

Apologies if this is the wrong forum but, what options are there? Dirt Farmer made a good set up and that may be the way I go. Wiser has what looks to be a good option but I really can't tell how it works from their web site. MK Precision has a unit but looks like it needs a bi pod and is sort of spendy for what it is.

Goal is to be able to shoot groups and record velocity with the secondary goal of not shooting my magneto speed unit. I like the DIY options so post photos if you have a set up please.

I'm in the design-stage of making a fixed mount for my magneto speed "bayonet" that I can position underneath and just forward of the muzzle but not connected to the barrel. I imagine the same results could be accomplished with a short pic-rail attached to the underside of front sling-swivel stud and extra-bipod stud IF YOUR STOCK CAN HANDLE THE WEIGHT AND IT DOESN'T AFFECT THE OTHERWISE NORMAL BARREL HARMONICS. I would be interested if someone else already perfected something like either of these two methods as I'm not too proud to copy someone else's work but I am lazy and don't like unnecessary labor, much less learning the hard way from mistakes of my own doing.

I just did that this spring. It turned out the path I chose (after a little thought) was pretty simple, and works well. Used a Caldwell Rock front rest. Will post a photo soon.

Tag

Here it is. As noted earlier, bought a Caldwell Rock front rifle rest at a local store, as I recall for $50. The flat plate on top where the chronograph is mounted is normally where the front pad is attached with Velcro straps. Had to drill a hole for the screw that goes into the bottom of the MS.

John,
How close does your barrel have to be to the chrono to get reliable readings?

Thanks, Dinny

The directions for the chronograph say the bullet should pass no closer than 1/8" above the sensor, and not more than 3/8". This can easily be determined with a cleaning rod through the bore.

I have used my MagnetoSpeed for 250 Savage up to 300 WSM and a few in between on the barrel as design intent. Have had no experience that would make me want to have the transducer independently mounted. YES, it effects point of impact, but the best groups with the bayonet attached are the best without. When load development is done, I take a couple shots to zero. Usually 1-2 inches high. I don't find this to be so inconvenient to need a isolated mounting system. Typed this on more than one occasion, and I definitely seem to be a minority on this, but it works for me.

oldotter,

Good for you, but my experience is completely different--as is that of many other shooters.

I have seen plenty of rifles where point of impact AND group size have been affected considerably. One example was during a range session with three friends. I got there a little later than the others, and they were puzzling over a new (and very accurate) rifle one of them had just tested with handloads. One load had shot more accurately than several others, so they put a Magnetospeed on the muzzle to chronograph the vleiciuty. The load not only didn't shoot very well with the chronograph on the muzzle, but 2-3 inches higher.

Sometimes POI and group size don't change with a Magnetspeed on the muzzle, but in my experience that can only be counted on with heavy-barreled rifles. With sporter-contour barrels, of any weight, there is a distinct possibility of variations both in accuracy and POI.

Since I regularly shoot 4-5 rifles during each range session, using a Magnetospeed mounted on the barrel means I have to shoot everything twice, to make SURE there isn't a difference in group size--and sighting-in requires more shooting as well. Using the mounted MS saves time, money and barrel life.

Edited to add that mounting the Magnetospeed on a stand also saves time in another way: I don't have to keep switching it from rifle to rifle during a range session, instead just shooting over it, much like a light-screen chronograph.

This has been my experience as well. Even out to 1000 yards. With sporter weight barrels.

My groups at 100 yards with the bayonet attached are patterns not groups. Also it is a PITA to fit the bayonet to thin tapered barrels.

I use mine only anecdotally. During load experimentation. I'll say "I wonder what velocity I'm getting" and strap on the chrono. Mostly I don't even target the rounds I fire, just sling them into the dirt. For me the big sell is its compactness, ease of use, and liberation from having to drag along an extra tripod/platform. I would love a LabRadar but it's cost far outweighs my anecdotal curiosity about velocity. Note also I don't employ a chrono for statistical assistance in load development- I have long since abandoned skating on the edge of high performance/pressure where a good chrono is invaluable for staying out of trouble.

I need to look at some way of rigging up a tripod as a mount for my MS. The benches I shoot on aren't long enough to use a front rest as a MS stand.

This is the unit I am considering if I don't do the Caldwell set up. Wiser bayonet mount: https://www.wiserprecision.com/products/chrono-mount

I have seen groups affected and have also had the unit slip which ruins a string of velocity tests. I also have a table top tripod that could work for this as well.

I was looking a wiser system. Anybody try one of these with one of the picatinny rails you can attach on your front sling swivel stud?

Lou

Stupid question: Do you use another rest/sandbag to get the muzzle in approximate position over the chrono without touching it?

thanks

Yep--in fact I usually use the same brand of front rest for my range shooting. Between the two, it's easy to adjust so the muzzle "floats" a little above the V-slot at the rear of the bayonet, where the barrel is usually clamped.

MD, have you ever tried it with a suppressor?

Like JB noted, it's not that hard to keep the proper relationship, bore with bayonet. I check before each shot. You can use a cleaning rod, but after a while you learn to "eyeball" it close enough to get a reading without blasting the divice. The more the gun kicks, the more adjustment, getting the barrel back in the right position and in right relationship with the bayonet. It's really easier than it sounds, especially after doing it a while.

DF

JG,

No, I haven't. But wouldn't be surprised if it worked OK, depending on the diameter of the suppressor, though it might require some experimentation with the position.

Dirtfarmer,

One reason to choose a heavy base, like the one you used--which is also why I chose mine.

Haven't tried that, either. I think it would take more effort to get the relatinship right, may need a cleaning rod for that.

I'm posting the picture of mine, being we mentioned it. Some may not have seen it. Same idea as yours.

It takes a longer bench, like the one I built for the tailgate of my pickup. Works pretty well. Gibralter drum throne makes a great BR seat. Deer corn in the truck, headed to the camp; picture was taken a few years ago.

DF

With the Sporter model you'd likely have to position the whole unit in front of the suppressor due to its shape.

This is from the Wiser mount site:
Q: Will The Chrono Mount allow my MagnetoSpeed Sporter to work with a suppressor?
A: The geometry of the bayonet still limits its use, unfortunately, so it depends. See MagnetoSpeed's fitment guide for more information. We have; however, had a few customers position the entire bayonet assembly in front of their suppressors to get proper lift and gap to bore with good success. If you decide to run it in this configuration, we advise caution to be used so the exhaust gasses do not melt your bayonet strap.

"If you decide to run it in this configuration, we advise caution to be used so the exhaust gasses do not melt your bayonet strap"

Which is, of course, irrelevant if you don't use the straps. Would be interesting to try.

Free standing in front of the suppressor may be the best way.

Would have to be careful with alignment, may require a cleaning rod alignment after each shot, as "eyeballing" the relatinship, bore to bayonet with a suppressosr sitting on the end of the barrel, would be difficult, IMO.

DF

Got a Caldwell Rock Jr. and think this will be enough for the magneto speed mount.

That should work.

Just something solid enough, like JB said, that will hold it where you set it and not move around.

The free standing set up requires attention to detail, setting up each shot. You gotta get it aligned right every time.

I also take 4-5 rifle to the range, letting them cool while I shoot others.

Free standing beats the heck out of having to change the bayonet from barrel to barrel then back again. I may shoot one gun 6-8 times, cooling between groups. With 4-5 guns, that would be WAY too many swap outs, IMO.

I'd rather be concerned with precise alignment for each shot than doing all that swapping...

DF

Another brain fart...

With a suppressor, I'd get a wooden dowel as close to caliber size as I could find, one that would easily slide into the bore. I'd check bore/bayonet alighnemt between each shot. It wouldn't need to be more than 18" or so, just enough to index in the bore and extend over the bayonet.

Without a suppresssor, I can pretty well eyeball it. A big bulge on the end of the barrel would make that much harder, maybe impossible for any precision.

And, bayonet to bore alignment is essential to: (1) not blow up the bayonet and (2) miss recording the data. There is some leeway, but not a lot.

DF


Edited to add, with the suppressor, the dowel may have to be longer, long enough to pass thru the suppressor and into the barrel far enough to accurately establish bore axis and long enough to extend over the bayonet. 18" would probably be long enough without a suppressor. One would probably have to add suppresssor length for the dowel to work.

tag

The Wiser bayonet attachment is shown with a suppressed rifle. It has attachments for a bi-pod or a small rail that mounts on the sling swivel. This would be worthwhile if you have to use a cleaning rod for each shot.

How about a spacer taped to either the barrel or the Magnetospeed unit, could tape it on to the barrel or to the chrono, may want a different height for some barrels. Chunk of rubber of some type to keep it soft maybe.