What is an acceptable standard deviation for rifle hand loads vs factory rifle loads

Remtac said:
The lower your SD is the more accurate your average muzzle velocity will be for your ballistics program the higher your SD is the more inaccurate your average muzzle velocity will be for your ballistic program . Am I right or wrong , if I'm wrong what method should a person use to determine the best muzzle velocity number for the ballistic program?


Click to expand...

I guess no one has an answer .
 
Remtac said:
I guess no one has an answer .
Click to expand...

I find that I have to use the bullet - meaning I zero at 100 then follow my program to 2,3,4,500 and further if you can but I do it on a clean target so I can see the drop of the bullet compared to my program results . Then I adjust my velocity so the program matches my bullet performance . Hope this makes sense , I've read that people use the bullet coefficient to "true " their app but I find it works well with velocity
 
Hmmm. I am a low tech old fart.

I develop an accurate load for the ranges required - say 300 to 1000 yards for target shooting.

I then shoot at these distances and make a note of the elevation required.
 
Ganderite said:
Hmmm. I am a low tech old fart.

I develop an accurate load for the ranges required - say 300 to 1000 yards for target shooting.

I then shoot at these distances and make a note of the elevation required.
Click to expand...

Lol, me too , but I got one of these ballistic apps and they do save a guy Ammo and there fun to play with plus once I true my app to my load then I have my cheat sheet for different bullets and loads , I never was good at keeping up my paperwork

I never used my chrony before I got my ballistic app , then I had to get a magneto speed because my old chrony was such a pain , now I'm just trueing my app with results I get shooting and don't use my chrony much again
 
Last edited:
Keithjohn said:
I find that I have to use the bullet - meaning I zero at 100 then follow my program to 2,3,4,500 and further if you can but I do it on a clean target so I can see the drop of the bullet compared to my program results . Then I adjust my velocity so the program matches my bullet performance . Hope this makes sense , I've read that people use the bullet coefficient to "true " their app but I find it works well with velocity
Click to expand...

that makes sense also
 
Keithjohn said:
Lol, me too , but I got one of these ballistic apps and they do save a guy Ammo and there fun to play with plus once I true my app to my load then I have my cheat sheet for different bullets and loads , I never was good at keeping up my paperwork

I never used my chrony before I got my ballistic app , then I had to get a magneto speed because my old chrony was such a pain , now I'm just trueing my app with results I get shooting and don't use my chrony much again
Click to expand...

do you agree that the lower your SD is the more reliable your average muzzle velocity will be ?
 
Have you considered using Microsoft Excel to calculate your SD, the first 7 shots shows a SD of 10.765, the second set, the first shot is not recorded and showing 8.61 SD in excel with formula. Yes you are right the lower the SD the better your average of the velocity will be in the sample, it's all statistics in which the sample taken; results show a bell curve to the closest point to the median, mean or mode and the lowest SD will give you an idea of your best average velocity which in turn is one factor to better accuracy with that combination of load.
 
Remtac said:
do you agree that the lower your SD is the more reliable your average muzzle velocity will be ?
Click to expand...

For sure I do try my best to get low SD for my long range shooting , the further you go the more the deviation shows but I don't have the equipment or abilities of some
 
From my limited experience I have noticed that it's all about the cases. If your case weight has low variation so will your SD.
 
Suputin said:
Yep, I don't give a toss about SD. There are so many other things going on between you and a distant target that SD is a minor issue.
Click to expand...

THe lower your SD is the more accurate you average muzzle velocity will be ,the more accurate your muzzle velocity is the more accurate your firing solution will be from your ballistic program .
 
Are you a shooter or a mathematician?

"....some guys on here seem to think SD is not important , basically saying it don't matter if your SD is 7fps or 30fps all they care is that the load is accurate ."

Yes, exactly right. For long range loads, I develop the load at 900 or 1000 yards. My definition of a good load is a minute of elevation, or better. I find that load with 0.3 gr increments, and some different OALs. Once I find that load, I write in on the wall of my loading room and make that ammo.

Sooner or later I will Chony it out of curiosity, to see what the velocity is. In my 308, I know it will be between 2950 and 3050 fps (155 gr bullets). The Chrony also spits out the ES and SD. That is when I find out what the number is and you are right "it don't matter if the SD is 7fps or 30fps..."

If they have a handloading competition based on SD, then I would tweak ammo for the best SD. Other than that, I won't
 
Last edited:
You must log in or register to reply here.
Back
Top Bottom