Thread: Testing a conventional approach to load development

Originally Posted by gimp

4x 5rd groups actually.


Barrel cooled between 5rd groups (even though it doesn't actually matter), fired each load alternately to minimise any differences in fouling etc. Fired 10rd of each then went and did other stuff (helping others sort guns) for a couple of hours then fired the last 10 of each. Wind very low and consistent, <1ms 12 o'clock. Temperature consistent at 12 degrees C through the day (kestrel). Parallax dialled out.

Shooting high numbers of shots through other rifles with different loads clearly demonstrates differences in precision, e.g. .223 with handloads 0.9moa group for 20, 1.5moa for 20 with factory "match" ammunition.


How do you propose to quantify a valid understanding of the real precision capability of a system?

Barrel cooling does matter, as do plenty of other factors, how much they matter? that is not exactly known. Getting up and changing your shooting posture, has an impact. Parallax dialled out will minimize parallax, not eleminate it completely. fouling can change things too. All minor effects, that generally are not too important when dealing with general hunting precision requirements. But when you are looking at 0.25 or 0.5 moa differences, these minor influences do start to matter. Another thing is poi shift: since you fired all those shots into the same group you would not know if later 5 shot groups had a different poi, compared to earlier ones. So even if one of them was tighter to start with it would be hidden if any poi shift occured. Essentially any "signal" (if it is there) is hidden within other "noise", and thats why both of them show no significant difference.

Not saying you are a bad shot or anything (you clearly are not!). Essentially what you did is try to "prove" that for 2 charge weights, both of which already shot very well in your rifle (for general hunting purposes) there would not be a difference, (despite 3 shot groups indicating that there would be) by introducing a many other factors uf unknown impact into the system.

Your system here (rifle, loads, you) seems to give good (

Originally Posted by STC

Barrel cooling does matter, as do plenty of other factors, how much they matter? that is not exactly known. Getting up and changing your shooting posture, has an impact. Parallax dialled out will minimize parallax, not eleminate it completely. fouling can change things too. All minor effects, that generally are not too important when dealing with general hunting precision requirements. But when you are looking at 0.25 or 0.5 moa differences, these minor influences do start to matter. Another thing is poi shift: since you fired all those shots into the same group you would not know if later 5 shot groups had a different poi, compared to earlier ones. So even if one of them was tighter to start with it would be hidden if any poi shift occured. Essentially any "signal" (if it is there) is hidden within other "noise", and thats why both of them show no significant difference.

Not saying you are a bad shot or anything (you clearly are not!). Essentially what you did is try to "prove" that for 2 charge weights, both of which already shot very well in your rifle (for general hunting purposes) there would not be a difference, (despite 3 shot groups indicating that there would be) by introducing a many other factors uf unknown impact into the system.

Your system here (rifle, loads, you) seems to give good (

So how much shooting have you actually done? Ever shared your results? Shot in competitions?. I'd love to hear about the basis for your inputs on threads like this. Do tell us.

Originally Posted by Makros

Would appear to me that many prefer to halve group sizes by stopping shooting halfway towards a larger group.

the best is a one shot group right where you want it to be!

Originally Posted by Tentman

So how much shooting have you actually done? Ever shared your results? Shot in competitions?. I'd love to hear about the basis for your inputs on threads like this. Do tell us.

And I would love to see people like you keeping their frail egoes out of it...

Originally Posted by STC

Barrel cooling does matter, as do plenty of other factors, how much they matter? that is not exactly known. Getting up and changing your shooting posture, has an impact. Parallax dialled out will minimize parallax, not eleminate it completely. fouling can change things too. All minor effects, that generally are not too important when dealing with general hunting precision requirements. But when you are looking at 0.25 or 0.5 moa differences, these minor influences do start to matter. Another thing is poi shift: since you fired all those shots into the same group you would not know if later 5 shot groups had a different poi, compared to earlier ones. So even if one of them was tighter to start with it would be hidden if any poi shift occured. Essentially any "signal" (if it is there) is hidden within other "noise", and thats why both of them show no significant difference.

Not saying you are a bad shot or anything (you clearly are not!). Essentially what you did is try to "prove" that for 2 charge weights, both of which already shot very well in your rifle (for general hunting purposes) there would not be a difference, (despite 3 shot groups indicating that there would be) by introducing a many other factors uf unknown impact into the system.

Your system here (rifle, loads, you) seems to give good (

Ok so there are several layers we're going to have to get through.


1. What is a sensible procedure for establishing the practical precision capability of a rifle system?
2. What is a sensible statistical test for comparing data when changes to the system are made, to detect whether or not the changes have resulted in a meaningful change in precision? (in this case the change to the system is a small difference in powder charge)
3. What is a sensible approach to load development?



Let's start with number 1.


What is your proposed approach for establishing the precision capacity of a rifle system? Defining rifle system in terms of the way that it is practically used - shooter, rifle, scope, and the specific ammunition.

What metric would you use? How precise would you expect your estimate of the precision capacity to be?

Originally Posted by STC

..Parallax dialled out will minimize parallax, not eleminate it completely...

Have no idea of the basis for your statement. Can you expand please.