CBTO/COAL measurement- margin of error

[Oldmauser]

I would like to share my CBTO and COAL measurements for 6.5 CM done for the first time using the Hornady tool. I measured them 3 times and here are the results:

1.attempt COAL 2.8545/CBTO 2.223

2. attempt COAL 2.8590/ CBTO 2.222

3. attempt COAL 2.860/ CBTO 2.230



Should refer I my seating depth to this or should I rather ask a more experienced colleague to verify this?

 

[salks]

Are you attempting to find your lands? I often get some difference finding lands with the Hornady gauge . COAL really doesn't matter if you are looking for lands. If you have someone that can verify it would be great. It's kinda of a feel type thing using the Hornady gauge. There is a video on you tube "finding land length exactly" great way to find them exactly. If I'm within .002-.003 with Hornady gauge I just average it.

 

[spife7980]

Do it more times until you get consistent results. You’ll know when you get confident in what you are doing.

 

[Oldmauser]

Thank you guys. I was doing this for the first time. I watched a couple of youtube videos and I follow the same procedure: I push the bullet until I feel resistance. Then I pull out the tool, the bullet sticks in the lands, I push it out gently with a rod and then I stick it again in the Hornady OAL Gauge. Finally I measure both CBTO and COAL.

 

[InTraining]

You may have to seat the bullet in a case at that COAL to accurately measure the CBTO. Just my opinion.

 

[Oldmauser]

that's exactly what I did.