Chrono Question

[scott63]

So I've been reading everything I can on load development and it would seem to me the common way of doing things is to try to find a node where your ES between 3-5 rounds is very small. Then load in the middle of the node to verify ES, if confirmed then start adjusting COAL to find the bullet depth node.
My question is, is it pretty much pointless to embark on this adventure without the latest from Labradar or Magneto Speed? I have an old chronograph that up until now I never worried about how old it was, I just used it to make sure I wasn't about to rip a hole in the time/space continuum along with any other over pressure signs. Is it super accurate? I don't know, to be honest that isn't something I've ever worried about before now.
Thanks,
Scott

 

[ChrisInKY]

Scott,

First: You have to load properly to get your ES very small. Inconsistent and/or bad practices are your worst enemies when it come to ES. Second: The are countless ways to affect your ES once you're out on the range. You have to master all the tricks of minimizing ES (i.e. you're not going to consider your cold bore velocity from a fouling shot as part of your ladder, are you?).

Strapping a MagnetoSpeed device to your barrel is going to change your barrel's harmonic. Then what? Now you've got potential erroneous flyers to address.

Chronos are one of the first places where shooting sorcery takes root. As long as the one you have is consistent in its measurements, it doesn't really matter what the read-out happens to be. All of your calculations will be consistent (unless you're not even using your chrono correctly) to that readout and you will be able to effectively engage targets out to extreme ranges. Worst case ... you may be guessing at how many ft lbs of energy are being delivered to your target.

The way you figure out if your chrono is consistent is to run a second (consistent) chrono together with yours. Shouldn't cost you more than three to five rounds. If you want to spend $300-$500 to ensure your peace-of-mind, no on here will be able to dissuade you.

Cheers!!
Chris

 

[codyadams]

I have a cheap optical chrono, and it works....but I still want a lab radar. It gets you in the general ball park, where is the lab radar and magneto speed chrono's are more precise but cost more, or in the case of the magneto speed, make it challenging to do accuracy load development and speed testing at the same time.

 

[scott63]

"Strapping a MagnetoSpeed device to your barrel is going to change your barrel's harmonic. Then what? Now you've got potential erroneous flyers to address."

I understand this, the velocity testing is separate to find the node, then the COAL testing is done after the lowest ES is found. I will ask around if anyone at the range where I shoot has something newer to compare velocity, or better yet a magneto speed.
Thanks,
Scott

 

[ShtrRdy]

Your optical chronograph should be fine. If you fire a shot thats quite different than the other shots then ignore it

 

[ChrisInKY]

after the lowest ES is found.

I believe this is what you're chasing. What worked for me (in order of magnitude) was:
1. Annealing. It's simply built-in forgiveness where neck tension is a concern.
2. Neck Turning. If the neck wall thickness is uniform in all of your brass ... you are able to confidently Neck Size.
3. Neck Sizing. Getting the right bushing, to squish that neck, over just the right amount of distance ... this is going to cost you a LOT of dollars ... LOL.
4. Bullet Lubrication. I'm going to withhold comment here and hope one of the forum's experts will step up and shplain the modern ways in which this is achieved. I'm still in the dark ages cheating with Imperial Dry Neck Lube.

There was once this dude ... named Varmint Al ... http://www.varmintal.com/arelo.htm

The skies of Kaintuck opened above me this afternoon. I was awarded three solid hours of personal range time. My adjusted ES was a single digit on each group. The worst five-shot ladder group @ 100m was 1.043 MOA. The best was .28 MOA. I'd guess the average was ~.7 MOA. Haven't found the high-end node yet in this ladder. Wish me luck, brother.

 

[Lefty7mmstw]

get an Oehler 35 (clocks your shots twice and flags potential errors), and forget it... I swear, we haven't advanced much in the last 25 years in this game. My father at one time made his own chronographs using tin foil laminated to paperboard and hung in a frame, then shot through; he had a Motorola chip programmed to clock the hits and display a vel. on a digital display. No optical error, and no worse than a magnetospeed as your shots are wasted either way. It's funny when you have an electronics engineer as a father who is an avid shooter.