Chrony advise.

[beleg2]

 

I never chrono my muzzleloading rifles and I would like to do it.
No that I do not like to do it, just read that I have to protect the Chrony from powder residue.
How do you protect your Chronograph? (If you do it)
Also, at what distance from the muzzle do you install the Chrony?

Thanks
Martin

[northmn]

I protect my Chrony from residue and bullets.  I took and built a frame to hold two pieces of 1/4 in angle iron in front of the unit.  They are held such that the back of the  V is pointed at me to give deflection.   Drilled one chrony with a scoped rifle and decided that a little deflection may help on the new one.  My Chrony has a remote read on the bench fed by a phone wire that limits the distance between them.  At about 15 feet I have had no residue problems so far.  Be nice to see results from someones Else's tests.  Some folks seen to think that if you see a velocity in a book that that load is what you will get.  Sometimes you get less, sometimes more.

[451whitworth]

i built a "blast box" which looks basically like a shoe box made from wood with a 1/4" steel plate screwed to the front face and a threaded insert on the bottom for the tripod. the chrony sits inside with only the guide wires and shades exposed. i only did this of course after i ruined my first chrony when a gas check from a cast bullet came off and smashed the LCD readout screen.

[Gene Carrell]

Steel deflection plates is interesting. I use heavy plexi plates for protection, set crony about 10ft out and shoot off a rest  at a target only. From a rest at a target is key to avoid making a hole in crony. Chronographed my Whitworth and Rigby last weekend with no problems.

[northmn]

Shooting from a rest is also advisable.  When I chronographed the 12 ga round ball I set up a dot before chronographing to make sure it would shoot close to where I was pointing it.  Mine also has extensions for arrows and shotguns to set the white reflectors up higher.

DP

[beleg2]

Thank for your advises!
My Chrony have no extension so I have to see the display.
I will try to protect it with some plexiglass.
Thanks
Martín

[Daryl]

Martin- try to get either UHMW (Ultra High Molectular Weight {polyethylene}) or HDPE (High Density Polyelthylene). Normal plexiglass is brittle and may merely disintegrate instead of deflecting the projectile.
: I set my screens up at 10' and have no problem with residue. If residue clogs the 'eye's, you can merely use a "Q" tip and warm water to clean them.

[Harnic]

I've never shot over my Chrony with a muzzle loader.  What, if any effect does the much slower patch crossing the sensors have?  My patches go a lot further than 10 feet.

[northmn]

I had pretty consistant results,  the patch missed the screens most of time or was too late as the ball was already registered.  I have  also chronographed several shot loads and have found no wad effect but have found the MV's of factory loads used as a standard to be close to publications.  If we do not chronograph how are we going to gather information and make something relatively simple like BP shooting more complicated to keep eggheads like myself happy?

DP

[Daryl]

Harry- the patch or wads are always behind the ball or shot so the projectile is registered only.  When shooting shot over the chronograph, I remove the rods and place a board in front of the chronograph with a virtical red or black arrow indicating the eye location.  The board doers pick up the odd shot which might have badly damaged the chronograph. Shot hitting the wires may rip them from the plastic holders and that wouldn't be a good thing.

 As you know, time to time you'll get a wonky reading - such is normal with most any chronogrpahs when shooting most calibres. I've used Oehler, Pact and several Chrony's - all have given virtually identical results. Funny thing, is I never got a 'bad' reading when shooting the very large 'bore' guns, BP or smokeless.

[Harnic]

Which would have recorded at Heffley Daryl, Max's ramrod or prb? 

[Daryl]

I suspect Max's ramrod would have destroyed the chrongraph - in a rather spectacular manner as well - no recording worth writing down.

[Harnic]

Sure gave him a whack on the shoulder!