Chronographs

[kcstott]

The Ballistic AE app I have wants the muzzle velocity so, without a Chrony am I going to get that number? I apologize in advance if that's a mornic question but I'm kind of at a loss to figure that one out. So in my mind, I kind of need to know that number to figure out other things like bullet drop don't I? Again, if it's a moronic question, I apologize and if someone would be so kind as to point me to a place that will help me figure that out, I would be very appreciative.

What got me thinking about this was the guy posting asking about wanting to make a perfect shot right out of the gate. One shot, one kill in a hunting situation if you will and I didn't want to hijack his topic.

Thanks for the good info folks.

Factory ammo is going to be very close to published velocities. Barrel length makes a difference but not much. You can shoot a 100 yard group then bump it out to 300 and see what the drop is reference that to your chart and see how close the velocity matches. you'd be surprised how little effect velocity has on drop if you are within 100 fps of actual. You won't see any gross errors until out past say 1000 yards.

Keep in mind these are very broadly speaking and very general terms.

When you get to playing with the app you will start to split hairs but for the most part you Chrono will collect dust on a shelf.

Once you start to figure in the Chrono's error on top of your error you will see that you can never be anywhere near right on the money and any range beyond say 800 yards.

[CNC_Apps_Guy]

I bought my last box of factory ammo for my .338LM a month or so ago

I've got a couple hundred cases and I'm off to the reload races.

Hodgdon H1000, Hornaday 250gr. HPBT Match projectiles (only been shooting 250's so I figured I'd stick with 'em), and Federal Match primers.

So, that being said, should I just do my work ups and forget the chrono? I'd love to save the $$$ and buy more powder.

Thanks.

[Fjold]

If you're reloading, you need a chronograph. Even if you shot the load at different distances, you have to shoot a lot of loads to insure that what you are seeing is actual drop versus the normal dispersion due to group size.

[kcstott]

Yeah i have to agree if you are reloading you better have a chrono.

I only use mine for my rifle loads and every great once in a while for my pistol loads but yeah consider it a piece of safety equipment too. even though velocity is no indicator of pressure. it can tell you when you need to start keeping an eye on things

[CNC_Apps_Guy]

Ok. Thanks guys!

Is a Kestryll mandatory as well?

[Ahhnother8]

If you're reloading, you need a chronograph. Even if you shot the load at different distances, you have to shoot a lot of loads to insure that what you are seeing is actual drop versus the normal dispersion due to group size.

Yep!!

I NEVER test ammo without a chrono. And although good for getting bullet velocities, nothing good can come from the ones that attach to the barrel. Just last week, it was very windy so I removed the mirage band and the point of impact moved 2 MOA. At long-range EVERYTHING matters. Shoot ammo with an Extreme Spread in velocity over about 30 fps and you are screwed. Group size and shape are critical at long and short range, but at long range the chrono numbers matter too.

[dskit]

It's true that the magneto will move your POI, but I have found groupings to be generally not impacted.

[Ahhnother8]

It's true that the magneto will move your POI, but I have found groupings to be generally not impacted.

That is interesting. I have never heard of anyone testing that. Any type of weight on the barrel has to act like a tuner to some degree. It might make things better or worse.

[micro911]

I used to have Ohler 35P. It shows digital readout and prints out the data for you. I gave it away when I moved away from long range/rifle shooting. I am back and need one again.

[kcstott]

That is interesting. I have never heard of anyone testing that. Any type of weight on the barrel has to act like a tuner to some degree. It might make things better or worse.

And thats why I said no way would I own a chrono that hangs off the barrel

[thenotoriousmo]

When I lived in a normal state almost everything was shot suppressed. there was a very repeatable poi change from the can being on and off. But i never noticed a significant change in the group size. I bet if the option was available, everyone would be hanging almost a pound off the end of the barrel.

I own a magnetospeed and have notice the very same thing, although the change is not as drastic.

[30-338]

Still waiting for this to be released.

http://www.mylabradar.com/

Me too....I hate it when they tease you with release dates and then over a year delay. The design and promised accuracy are tantalizing. I especially like the fact that you won't have to go through the issues involved in setting up a chronograph at the range, during cease fire with the oversight of the rangemaster....and all the attendant problems.
I have been impressed with the accuracy of the Magneto speed device also. When they first came out, we set one on a rifle and then set up an Oehler 12 feet in front of the rifle. The Oehler has an excellent reputation for accuracy...and we compared results from the barrel mounted unit and the Oehler. They were just what you would think they should be. Typically the Magneto speed unit gave a reading about 10 feet or so FPS faster then the Oehler. There were no anomolous readings. The only thing wrong with the magneto speed units are that they hang a weight on the end of your barrel and usually affect the precision of the groups. We figured that for pure speed measurement the Magneto Speed in excellent...but you have to work up your accuracy load without the unit attached....Some of the really thick barrels are not afffected as much. My 2 cents 30-338

[thomashoward]

I've used a Chroney never worried about sky screens. I don't chrono much these days

[orangeusa]

I've used a Chroney never worried about sky screens. I don't chrono much these days

Is that an outhouse in the background?

[thomashoward]

never used it for that.its gone now
we jus do it in the woods