Magnetospeed on a 16" barrel w/ 13.5" hand guard

[CMB]

I guess the bottom line question is to those using the V3, how crucial is the ¼ inch window?

There is not enough room between the end of the hand guard and the muzzle device (dragon ASR) to mount the V3. One option is to mount it to the ASR blast shield but this puts it pretty far out.

If I use a rail section in the front most m-lok holes (current rail section is magpul) and the rail adapter the sensor surface sits over the ¼", very close to ⅜ of an inch. The magpul section is fairly thick. I figured I could try it this way or try to find a "low profile" section as the rail adapter is not adjustable. Another option could be to machine the rail section to remove material where the rail section meets the hand guard.

Has anyone else ran into this?

Thanks All-

 

[Varminterror]

The gap between the bore and the bayonet is critical. The distance fore and aft from the muzzle across the blast throat is much less critical.

 

[CMB]

Thanks for the feedback. I guess I look for a low profile rail section. Ofcourse Amazon is the easy button to find one but all the made in Ch#na crap is quite bothersome.

 

[Varminterror]

3/8” of radial spacing should still pick up with the sensitivity control adjusted. If you are able to push the bayonet more forward and Mount closer to the bore, I would do so. I have had no issue with missed reading or misreads even pushing the entire blast throat forward of the muzzle. For example, the shell of my Omega 300 is uneven, so I mount the bayonet on the forwardmost portion of the tube which is uniform. This positions the bayonet far too far forward by specification, but it has still read reliably for thousands of shots without issue.

 

[CMB]

Thanks - that's encouraging enough to give it a try.

Cheers,

 

[Walkalong]

Turning up the sensitivity can help if it’s too far below the bore, can only get so far though

 

[taliv]

I think there are some options for 3rd party mounts to rails. They were mostly so people could chrono without influencing harmonics but it would fix this problem too.

if not you could prob 3D print something

 

[LoonWulf]

..... I took my handguard off when I chronographed my 350 with a 16-in barrel and 15" handguard.....

 

[sparkyv]

I agree. These positions work well for me.

The gap between the bore and the bayonet is critical. The distance fore and aft from the muzzle across the blast throat is much less critical.

 

[CMB]

I think there are some options for 3rd party mounts to rails. They were mostly so people could chrono without influencing harmonics but it would fix this problem too.

if not you could prob 3D print something

Interesting - do we have a good source for the 3rd party mounts?

 

[CMB]

..... I took my handguard off when I chronographed my 350 with a 16-in barrel and 15" handguard.....

Great Option! I should have thought of that one.

Once again - thanks Guys!!

 

[Varminterror]

Interesting - do we have a good source for the 3rd party mounts?

I have the MK Machine mount, but don’t use it often enough.

https://mkmachining.com/product/mk-machining-gen-iii-magnetospeed-mount/

 

[CMB]

I just wanted to follow up. I believe I have it worked out with the rail adapter. The sensor surface is still about ⅜ of an inch away. I turned up the sensitivity to "8" and received readings in the high 2700fps for 24.5 grains of X-Terminator under Everglades 55 grain version 4 seated @ 2.230, all FC cases trimmed to 1.750. (Yes these need trimming) Does this seems reasonable? Can I trust the readings with a gap of ⅜ or do I need to come up with a different mounting method? I wish I had access to another cronograph for comparison. Never the less, this adds a whole new level to reloading. It's almost like without being able to measure the speed I was just guessing. Now a can quantify the different charge weights, seating depths and bullet weights.

Thanks Guys-