Velocity question

Any suggestions on how to achieve more consistent velocities in a 30BR? :confused:

What yardages are you shooting? For 100/200/300 Score ore group, I just tune for the best aging capability and shoot it.

Typically, with 4895 and 112's, I will get total spreads of 10/15 fps.
 
What yardages are you shooting? For 100/200/300 Score ore group, I just tune for the best aging capability and shoot it.

Typically, with 4895 and 112's, I will get total spreads of 10/15 fps.

Jackie meant H4198, not H4895. I think his mind has been on the PPC and 4895 lately.

Michael
 
How wide of a spread is your velocity? I was seeing 60-70 variation once due to too much jam, I went to a slight jump and velocity was less than 20 diff.
 
More info

  • Jackie, I shoot 1-2-3 Score
  • Bluechip, see attached Spreadsheet
The reason for my original question was my ES & SD have been increasing, scores decreasing, over the past month or so. Prior to this the SD were high teens - lo 20's. SD 3.4 - 7.6I am using the same lot of 4198, same load, bullets & seated .005 into landsAs you will note from the spreadsheet both ES & SD are up. Also, I have noted the Temperatures & Humidity at the beginning of each match.I used a Lab Radar to collect this data.
 

Attachments

  • 9-24-17 Sulfur.xlsx
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Shinny

I would try to get your average velocity up around 3040-3060fps it's kind of a sweet spot in my 30BR's. It may or may not work for yours.

I was stuck on ES & SD last year. Then while working up a load with my labradar for a new 30BR barrel 3 shot groups I shot 3014,3014,3015 fps none of the holes were touching! increased powder charge for the next 3 shot group it was 3042,3073,3057 fps they all went in the same hole! Since then I only pay attention to average velocity 3040-3060fps.

It seemed to work better for me! This year I stayed around 20-23 X's at 100yds.

Russ
 
Interesting

I would love to see someone write a paper where they could explain why an increase in ES and SD was inductive to increases in accuracy. Interesting.
 
I would love to see someone write a paper where they could explain why an increase in ES and SD was inductive to increases in accuracy. Interesting.

For Mr. Stiner's example the paper need only state: 100 yds. At short range tune trumps spread.
 
For Mr. Stiner's example the paper need only state: 100 yds. At short range tune trumps spread.

Yep. I'd rather have 20 fps ES on top of a node than 5 fps mid-deflection.

Shinny - as you know, I took the plunge and bought a Lab Radar after we spoke. Tried it last weekend and am impressed. I'll tune and find nodes on paper....but this Lab Radar definitely helps you stay in-tune as conditions change.

-Lee
www.singleactions.com
 
Why not

Yep. I'd rather have 20 fps ES on top of a node than 5 fps mid-deflection.

Shinny - as you know, I took the plunge and bought a Lab Radar after we spoke. Tried it last weekend and am impressed. I'll tune and find nodes on paper....but this Lab Radar definitely helps you stay in-tune as conditions change.

-Lee
www.singleactions.com

Why not try for a 5 fps SD on top of the node ?
Then again this may shoot worse according to the way some shooters analyse the data.
 
Why not try for a 5 fps SD on top of the node ?
Then again this may shoot worse according to the way some shooters analyse the data.

There's nothing wrong with that. All I'm saying is I don't initially tune with a chronograph. I let the paper show me what the gun wants. Now that I have a Lab Radar, I'll pay more attention to ES & SD. But I doubt I'll constantly chase them.

Last year I chrono'd one of my most consistent and tightest shooting PPC loads. ES and SD weren't that great, but that charge and seating depth worked. Over the same chronograph, I shot a load I knew was in between nodes. ES and SD looked good, the paper didn't. Go figure.

-Lee
www.singleactions.com
 
I would love to see someone write a paper where they could explain why an increase in ES and SD was inductive to increases in accuracy. Interesting.

I’d be curious as to whether the average deviation in velocity had the same values between different powder types eg 133 / 4198, or between different cartridges.
 
I’d be curious as to whether the average deviation in velocity had the same values between different powder types eg 133 / 4198, or between different cartridges.

Considering the parameters needed to prove Statistical Significance, most will find it impractical to do such testing.

Landy
 
Considering the parameters needed to prove Statistical Significance, most will find it impractical to do such testing.

Landy


No Doubt…

To put a value on the different characteristics on NC in relation to the properties of a loaded round is nothing less than stochastic.
 
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