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Since you have a chronograph you can load one round at each powder charge going up in 1% increments.
If your baseline starting load is 23 grains you would go up in 0.2 grain increments. If your starting load is 52 grains your incremental increase would be 0.5 grains
Now go to the reloading bench and load up one round using your incremental charge weight from book minimum to book maximum and maybe two to three rounds above book maximum.
You set up your chronograph and have your notebook and a pen handy and shoot your rounds evenly spaced for time without ever looking at your target. You can measure the base of the case to make sure you are not pushing the charge to hot. 0.001 casehead expansion is your limit.
Now you plot on a piece on paper your velocities in a vertical pattern going from low to high but you put the change in velocity next to the powder charge.
What you should see is a hourglass looking change in your velocities something like this.
2850 FPS
2874 FPS +24
2890 FPS +16
2905 FPS +15
2918 FPS +13
2940 FPS +22
2965 FPS +25
2983 FPS +18
3000 FPS +17
3012 FPS +12
3035 FPS +23
3078 FPS +43
3148 FPS +70
This would show you two nodes one at 2918 FPS and another at 3012 FPS plus pressure problems at 3078 and above.
An incremental powder increase would normally produce an incremental velocity increase with two exceptions.
Exception one is when your near a node the increase is less.
Exception two is when your near high pressure the increase is nonlinear.
If you never see a velocity change below 35 FPS it's a good bet your primer isn't the best choice for your combination and you need to try something else.
Let the target and the chronograph pick your load despite what you might read on the internet.
With the 6BR and 6 Dasher cartridges there are powder primer combinations that are amazingly accurate but they are range specific.
The best combination at a sea level range in California might be Varget and a CCI BR4 primer while in Montana at 6000 feet that same gun might prefer H4895 and a CCI 450 Magnum primer.
Both camps will post pictures and beat there chests telling you about all the fake wood trophies each combination has won them but you need to remember the conditions and the location may make a difference.
In my opinion accuracy trump's everything even in a hunting rifle but others will post that you go for maximum velocity and then adjust your seating depth and take whatever accuracy that produces.
Who is right is up to your own needs as plenty of deer are killed each year with factory ammo and less than stellar guns.
If your baseline starting load is 23 grains you would go up in 0.2 grain increments. If your starting load is 52 grains your incremental increase would be 0.5 grains
Now go to the reloading bench and load up one round using your incremental charge weight from book minimum to book maximum and maybe two to three rounds above book maximum.
You set up your chronograph and have your notebook and a pen handy and shoot your rounds evenly spaced for time without ever looking at your target. You can measure the base of the case to make sure you are not pushing the charge to hot. 0.001 casehead expansion is your limit.
Now you plot on a piece on paper your velocities in a vertical pattern going from low to high but you put the change in velocity next to the powder charge.
What you should see is a hourglass looking change in your velocities something like this.
2850 FPS
2874 FPS +24
2890 FPS +16
2905 FPS +15
2918 FPS +13
2940 FPS +22
2965 FPS +25
2983 FPS +18
3000 FPS +17
3012 FPS +12
3035 FPS +23
3078 FPS +43
3148 FPS +70
This would show you two nodes one at 2918 FPS and another at 3012 FPS plus pressure problems at 3078 and above.
An incremental powder increase would normally produce an incremental velocity increase with two exceptions.
Exception one is when your near a node the increase is less.
Exception two is when your near high pressure the increase is nonlinear.
If you never see a velocity change below 35 FPS it's a good bet your primer isn't the best choice for your combination and you need to try something else.
Let the target and the chronograph pick your load despite what you might read on the internet.
With the 6BR and 6 Dasher cartridges there are powder primer combinations that are amazingly accurate but they are range specific.
The best combination at a sea level range in California might be Varget and a CCI BR4 primer while in Montana at 6000 feet that same gun might prefer H4895 and a CCI 450 Magnum primer.
Both camps will post pictures and beat there chests telling you about all the fake wood trophies each combination has won them but you need to remember the conditions and the location may make a difference.
In my opinion accuracy trump's everything even in a hunting rifle but others will post that you go for maximum velocity and then adjust your seating depth and take whatever accuracy that produces.
Who is right is up to your own needs as plenty of deer are killed each year with factory ammo and less than stellar guns.
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