chronagrph/muzzleloader

[winmag76]

Is there any tricks to chronographing a muzzle loader. I was shooting this weekend and I was getting some very inconsistent readings. I tried it at 8', 10', and 15' from the muzzle and my velocities were from 700 fps to 2300 fps with 90-110gr pyrodex 250gr shockwave. I have no problem with center fire or bows. I'm kind of new with the chrony so any help would be appreciated.

 

[winmag]

If your bullet has a sabott or patch your not going to be able to fix the problemb. Also check to see if your powder cloud rolls thru it, or blocks the lighting.
If a belted bullet has no patch or sabbot, and the powder cloud isnt rolling thru, Then the only other thing I can think is that some kernals of ff (or pieces of a pyrodex pellet) arent burnt completely, and are following the bullet too closley to acquire an accurate reading.

I shoot a .490 Hornady roundball with a .015 pre-lubed patch. Im not up on the newer stuff, or how it burns, so Im just throwing suggestions out there.
Good luck