So I have been reloading 223 using a Dillon 550 with the following specs.
Winchester Brass
CCI Small Rifle Primers
Campro 55gr Copper Plated Bullets
23.4gr Hodgdon H335
Light crimp as I am shooting through an AR 15 14.5" barrel.
I ran two strings with my Caldwell Chrono and was rather surprised by the spread in velocity. Chrono worked fine only had 1 error out of 30 odd rounds (forgot to save the first string mutter mutter) rookie mistake.
1st
Average 2662ft/sec (9 shots)
Standard Deviation 125
Min 2492 Max 2831 Spread 339
2nd
Average 2720 (9 shots)
SD 154
Min 2528 Max 2943 Spread 415
Now this seems a bit wide to me. I have been very careful to check powder setup and every time I check, not every round but randomly, I get 23.4gr +/- 0.1 gr. The individual velocity values seem to be reasonably evenly distributed within the range. Not being distorted by 1 really off cartridge. I have checked the bullet weights and while there is some difference it is nowhere near enough to explain the overall difference.
I am new to chronos so I am not sure what to expect.
So I guess my question is. It this as good as I can expect from my current setup and or is there something I am missing.
Winchester Brass
CCI Small Rifle Primers
Campro 55gr Copper Plated Bullets
23.4gr Hodgdon H335
Light crimp as I am shooting through an AR 15 14.5" barrel.
I ran two strings with my Caldwell Chrono and was rather surprised by the spread in velocity. Chrono worked fine only had 1 error out of 30 odd rounds (forgot to save the first string mutter mutter) rookie mistake.
1st
Average 2662ft/sec (9 shots)
Standard Deviation 125
Min 2492 Max 2831 Spread 339
2nd
Average 2720 (9 shots)
SD 154
Min 2528 Max 2943 Spread 415
Now this seems a bit wide to me. I have been very careful to check powder setup and every time I check, not every round but randomly, I get 23.4gr +/- 0.1 gr. The individual velocity values seem to be reasonably evenly distributed within the range. Not being distorted by 1 really off cartridge. I have checked the bullet weights and while there is some difference it is nowhere near enough to explain the overall difference.
I am new to chronos so I am not sure what to expect.
So I guess my question is. It this as good as I can expect from my current setup and or is there something I am missing.


















































