Chrono or not?

Wrkn2hunt

Founding Member
Founding Member
Joined
Apr 24, 2015
Posts
356
Likes
2
Points
133
Location
Cooperstown ND
This was brought up in my rifle build forum so I figured I'd start a new thread. How many of you chrono your rifles? I used to do it to all of them but found out when stretching the legs it would end up quite a ways off anyway so just resorted to actually shooting and and adjusting my data to match. Its a few more rounds down range but I will always know my data is correct.
 


Kurtr

Founding Member
Founding Member
Joined
Apr 12, 2015
Posts
18,304
Likes
2,059
Points
758
Location
Mobridge,Sd
i do to get a starting point for building a table but secondly to know if my es and sd are acceptable. If there is big swings than i have to find out why as it is hard to be consistent when the loads them self are not
 

SDMF

Founding Member
Founding Member
Joined
Apr 24, 2015
Posts
10,929
Likes
649
Points
438
C'mon Labradar!!

No sarcasm here, if I'm going to chrono I like to do so in the 20-30 min prior to sunrise on a clear morning shooting from West to East with the rising sun @ my back and no shadows on the chrono. Then I compare against Quickload's predictions, run a table, then actually shoot so as to really see what's what.
 

Kurtr

Founding Member
Founding Member
Joined
Apr 12, 2015
Posts
18,304
Likes
2,059
Points
758
Location
Mobridge,Sd
the labradar does look like the real deal if only i had a spare 600 i would have one. Shot with the magneto speed a few times and that seems like a better option than the set up on a tripod and have your buddy shoot it square in the screen chronys.
 

Wrkn2hunt

Founding Member
Founding Member
Thread starter
Joined
Apr 24, 2015
Posts
356
Likes
2
Points
133
Location
Cooperstown ND
Ok so I have read from a few articles that the ES is far more important than the SD and most guys will do a ladder test working loads and find a broad sweet spot. This is how I do my work. I work in .5 gr increments and find that broad sweet spot then fine tune. And in theory should have a low ES. Which most of the guys in the article prove. I will chrono my new rifle now as I am curious but in theory should be.
 


Norske

Founding Member
Founding Member
Joined
Apr 24, 2015
Posts
600
Likes
5
Points
143
Location
Moorhead, MN
A chronograph will be of a lot of value to any handloader. Velocity is proportional to pressure, so if your handload in your rifle reaches the published velocity, it's time to quit adding powder. It's also nice to know the velocity, therefore trajectory, of accurate loads. Standard deviation means nothing unless the sample size is large. The only extreme spread that I care about is the holes in the paper target. I don't bother checking the speed of mild handloads unless I've seated bullets to longer than published overall length, which changes pressures.
The only thing you can use to estimate pressures is velocity. Nothing else is reliable, especially if it's a custom rifle with everything fitting nearly perfectly. For example, the loads published for the STW wildcats by the designing gun writer showed none of the traditional pressure signs. When checked by ammunition factories, they were found to be running near or even over 70,000psi. That's the pressure at which the bolt lugs will suffer metal fatigue.
Not everyone needs a chronograph, but every group of friends needs one.
 

2400

★★★★★ Legendary Member
Joined
Apr 24, 2016
Posts
8,580
Likes
44
Points
276
Location
Northern AZ
A chronograph will be of a lot of value to any handloader. Velocity is proportional to pressure, so if your handload in your rifle reaches the published velocity, it's time to quit adding powder. It's also nice to know the velocity, therefore trajectory, of accurate loads.

I agree with you. I use my chronograph when I work up loads to check the velocity so I can do more than guess where my bullets will be at different distances. I actually shoot at 200, 300, 400 to see if the data agrees too.

I enjoy hand loading and then checking my finished ammo on the range to make sure it does what I wanted it to. If it doesn't the back to the bench.
 

PrairieGhost

Founding Member
Founding Member
Joined
May 15, 2015
Posts
10,346
Likes
724
Points
443
Location
Drifting the high plains
I chrono everything. Then I adjust the velocities in my program until everything works. For example I have had scopes that move 21.5 inches when I actually dialed 20 inches. Changing ballistic coefficient didn't work so I had to add 45 fps to get the scope and impact to agree.
 

2400

★★★★★ Legendary Member
Joined
Apr 24, 2016
Posts
8,580
Likes
44
Points
276
Location
Northern AZ
I chrono everything. Then I adjust the velocities in my program until everything works. For example I have had scopes that move 21.5 inches when I actually dialed 20 inches. Changing ballistic coefficient didn't work so I had to add 45 fps to get the scope and impact to agree.

It nice to see another serious handloader here. I've looked but haven't found a loading section, is there one here?
 

Kurtr

Founding Member
Founding Member
Joined
Apr 12, 2015
Posts
18,304
Likes
2,059
Points
758
Location
Mobridge,Sd
SDMF has a labradar which is going to make traditional chrony obsolete. Between accuracy and ease of use I see no other way to go. I chrony my stuff then shoot it then use the correction factor on strelok if it is not matching. Most likley phony readings from the chrony when other problems are eliminated.
 


SDMF

Founding Member
Founding Member
Joined
Apr 24, 2015
Posts
10,929
Likes
649
Points
438
Another club member has an Ohler 35P, a 3rd the Magnetispeed. I'd like to set all 3 up and see what's' what. The 1st range session was certainly encouraging. Accuracy and especially longevity are the question marks now and only time/use will tell.
 


Recent Posts

Friends of NDA

Top Posters of the Month

  • This month: 87
  • This month: 80
  • This month: 74
  • This month: 70
  • This month: 67
  • This month: 65
  • This month: 60
  • This month: 58
  • This month: 56
  • This month: 55
Top Bottom