Chrony

[richmcgin 32]

Hi all, I have just brought a new F1 chrony and would like some advise. i have used one before but it was on a range at Bisley some years ago and belonged to the club, so what i would like to ask is how far from the muzzle do those of you that use them, place them, iam aware that muzzle blast from larger calibres can cause problems with some chrongraphs but iam only using it on my 223. anny advise on these things would be greatfully recieved.

[sako 23]

I think it states in the book a few metres for rf/cf or in front of the target depending on where you want to test the velocity. I bought it for an 80ft lb air gun but haven't tried it with any of my CF's yet so can't say for definite. Unless you shoot it you aren't going to damage it so just start a couple of metres away and see if you get a reading. I have noticed the light is an important part in taking the readings without error's popping up though.

 

Edit: Just read the book... 3M from the muzzle for high powered rifles and 1.5M for .22 RF

Edited April 10, 2012 by sako

[richmcgin 32]

Thanks for that sako .

[matt_hooks 188]

Most MV values are taken 10 feet from the muzzle, so the 3m above would be a pretty good approximation.

[richmcgin 32]

Yeah i have got it here now and had a bash with it yesterday, i put a couple of loads together from the lee manual and a few of my normal loads, surprise surprise the velocity stated in the Lee manual were within 5fps on both that i tried!!!.