Two Types of Chronographs

[alfsauve]

It's an old joke,

There are the chronographs that have been shot

AND

There are the ones that are going to be shot.


Despite my efforts to defy all wisdom and science, mine just joined category 1.   I was checking a 9mm load and I hit the diffuser support.  Actually I nicked the front one and caught the rear one pretty much full on.   No other damage other than shrapnel flying every where.  The bullet broke apart and the bent support ended up behind me about 8 feet!   

How did it happen?  Dim light.  Wrong eyewear.  Couldn't see the sights clearly.  I shouldn't have fired, but I just "KNEW" at that distance I wouldn't hit it.

Whew.   Well at least the base unit survived.

[Hazcat]

Glad yer OK, Alf.  And at least the unit is still working, just need a couple of coat hangers to replace the diffusers.

[Badgersmilk]

Kudose for being brave enough to post the report! 

As YET, I haven't place a hit on mine, but given that I'm usually using it with rifles...  It'll be a DOOZY when it happens!

"There I was.  Using the Chrony when this 16 point deer ran by!  I couldn't just pass up my chance!" 

Yeah, that'll be the story!   

[Pathfinder]

OK, cute story. So how were the round's ballistics?


 

Glad it turned out OK, no one hurt.

[tombogan03884]

 I can , snobbishly, with nose in the air, state that I have never killed a chrono.
Then, as I watch my toes scuffing dirt I will mention that every one I know who has actually used one has though.  

[Sponsor]

[alfsauve]

... as I watch my toes scuffing dirt I will mention that every one I know who has actually used one has though.  

Yep just add me to the list.


I was checking my new 9mm rounds.   1,043fps.   Just hot enough to insure a 125 power factor.   Taking them to a match tonight.

[m25operator]

The Chronie brand are handy, inexpensive and work, but I like chrono's with separate sky screens. Chrono is on the bench with me. Friend of mine killed his when he got a .454 Casull, and shot 180 grn hollow points through it at 2200 fps, until the bullet exploded in mid air and shrapnel got it, soft nose hollow point going too fast, just melted.

[Solus]

The Chronie brand are handy, inexpensive and work, but I like chrono's with separate sky screens. Chrono is on the bench with me. Friend of mine killed his when he got a .454 Casull, and shot 180 grn hollow points through it at 2200 fps, until the bullet exploded in mid air and shrapnel got it, soft nose hollow point going too fast, just melted.

Sounds like some of the Cofram munitions we had back in the mid 60s. 

[tombogan03884]

The Chronie brand are handy, inexpensive and work, but I like chrono's with separate sky screens. Chrono is on the bench with me. Friend of mine killed his when he got a .454 Casull, and shot 180 grn hollow points through it at 2200 fps, until the bullet exploded in mid air and shrapnel got it, soft nose hollow point going too fast, just melted.

Sounds like some of the Cofram munitions we had back in the mid 60s.  

These are new to me .
M25's post, OK, it's a physics thing, I assume barrel twist played a role as well, good enough for some one like me who's not big on science.

But Solus's post refers to something I'm clueless about. Could you expand on that please ?

[Solus]

COFRAM was an acronym for the munitions and also the name of the security classification required for access.

It stands for Controlled Fragmentation Munitions and could be fired by artillery with airborne detonation.

I saw a demonstration and it was fairly awesome.  Light wooden crates were set up in the target area and were reduced to splinters upon delivery.

Below is a description and then a link to a once classified document pertaining to the use of the munitions

The COFRAM (COntrolled FRAgmentation Munitions) rounds were the predecessor to what we call today as DPICM (Dual Purpose Improved Conventional Munition). It ejects smaller bomblets (like grenades) at a predetermined altitude above the target. These bomblets then rain down on the target and blow it all to hell as they explode.

http://www.dod.gov/pubs/foi/reading_room/690.pdf