Magnetospeed Sporter on (full length magazine tube) 336?

[huntinlever]

Took a bit of tweaking but the Magnetospeed Sporter chrony works well on my 45-70 guide gun, with its shorter magazine tube. On the other hand, attempted with my son's 336 to no avail - could get no readings, and that includes trying to mount it sideways as the bayonet falls between the barrel and the magazine tube. The only way I can think to do it would be to mount the bayonet upside down, but then I'd have to do two passes for each load - one for data, one for groupings, as I can't see with the bayonet blocking the view. I'd rather not do that.

Anyone have any success mounting the chrony on their levers?

While here, I like the chrony well enough - don't miss fearing the day I blasted the Comp Electronics diffuser chrony. However, on my .338 WM and my son's 30-06, I find it impossible to avoid the Magnetospeed's loosening up and slipping constantly. I feel like I'm cinching down a calf then standing on top of the tightening screw to lock it in. It still slips. Anyone experience this, and if so, did you cure it?

[lawdog941]

I would just do the 2 shot method. Kind of hard to get accurate groupings with a bayonet attached to the barrel with harmonics. I shoot for recording of velocity, find a node, then load some with different OAL to find the best grouping. Except for your first shot (cold), you can maintain a similar barrel temp by taking your time, retightening the bayo the same way, and firing again. it's a PITA, but it works. Usually 1-2 minutes between firings. I've never seen it mounted on a lever action, maybe contact Magnetospeed to see if they have anything that works. Best regards

[Larry Gibson]

"and that includes trying to mount it sideways as the bayonet falls between the barrel and the magazine tube."

If it is mounted on the side of the barrel the bayonet is aligned with the barrel/bore. I have done so on two different M94 Carbines and a Marlin 336 and the readings were fine.

[huntinlever]

"and that includes trying to mount it sideways as the bayonet falls between the barrel and the magazine tube."

If it is mounted on the side of the barrel the bayonet is aligned with the barrel/bore. I have done so on two different M94 Carbines and a Marlin 336 and the readings were fine.

Thanks. I did that, at least I think I did the same thing, and I got zero reading - nothing happened. I'd thought because I mounted at "90 deg.," (to right, let's say parallel to the floor) the bayonet was actually not aligned with the barrel, but sort of spanned the barrel and magazine tube and the unit detected no bullet passage.

[Larry Gibson]

Went down to the 'cave' and mounted my Magnetospeed on my grandson's 336. Here's some photo's. Note I used the thinner rubber mounting pad which puts the bayonet a bit above 90 degrees to the side. I also put my 30 cal suppressor alignment rod in the bore so you can see how evenly the bayonet lines up with the bore.

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I've only used mine with jacketed bullets and cast with GCs (copper and aluminum). Don't know if it works with PB'd cast bullets.

[huntinlever]

Went down to the 'cave' and mounted my Magnetospeed on my grandson's 336. Here's some photo's. Note I used the thinner rubber mounting pad which puts the bayonet a bit above 90 degrees to the side. I also put my 30 cal suppressor alignment rod in the bore so you can see how evenly the bayonet lines up with the bore.

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I've only used mine with jacketed bullets and cast with GCs (copper and aluminum). Don't know if it works with PB'd cast bullets.

That's really helpful. Thanks Larry, heading to the range to try it out. Beautiful rifle as well.

[huntinlever]

Well, for whatever reason, I wasn't successful. Tried everything or so I thought, and couldn't get any reading at all, so I had to go on groupings alone (which weren't bad at all, given his old man's decrepit eyes and the Skinner). Estimating right around 2500 fps with the LeverRevolution.

[BLAHUT]

Mine would slip; so I put a little contact glue on the web strap, now hasn't slipped for a little while, if it starts again, I will put a little contact glue on again.

[Shawlerbrook]

I used silicone tape under the strap and no slippage.

[huntinlever]

Thanks guys, that helps. Not so bad on the gg because of the shortened magazine tube, it really slips on the rifles (30-06, 33 WM) without front sights.

I just couldn't get any readings with my son's 336. My guess is that it's too far away from the barrel - of course, I got to the range only to find that the thinner pad was missing from the chrony box. I'll dig around or get a replacement. Though don't expect we'll be hunting much past 50 with the Skinner, and pretty pleased at that range with just the visuals, groups.

[Larry Gibson]

Did you try and jacketed as a test to make sure it's just not liking cast bullets? Also, there is a "sensitivity" setting that must be correct? Sorry about forgetting to mention the tape under the strap and also some two side sticky tape helps a lot on the rubber pad.

[huntinlever]

Did you try and jacketed as a test to make sure it's just not liking cast bullets? Also, there is a "sensitivity" setting that must be correct? Sorry about forgetting to mention the tape under the strap and also some two side sticky tape helps a lot on the rubber pad.

Hey Larry -

Yes, the 30-30 is the Speer Hot Cor 150 gr SNFP. I was getting readings on my gg 45-70 with its cast bullets, but as I said in another thread, the readings seem pretty bizarre given load data, and previous experience (i.e., previous load 39.7 gr/425 gr WFNGC avg. vel. 1700 (Competition Electronics shoot-through), while the Magnetospeed gave speeds on the lighter bullet about 100 fps slower, with the equivalent charge. So not sure if I trust the Magneto, at least for me. I freely admit I could just be doing something glaringly wrong as I know you and others have done extensive testing (I think it might have been you, who compared different chronys and said the Magnetospeed was close to other units' data?).

Anyway, going to end up returning the Magneto and bought my old Comp. Electronics from Midway. Hassle given public ranges and needing a cold range for setup, but I feel I got generally good data that corresponded decently both to groupings and to load book data estimates.