6.5 CM Bullet Comparator

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Mar 17, 2013
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I am beginning to load for 6.5 CM. My Hornady bullet comparator kit does not have an insert for 6.5 bullets. They have a #4 - .25 & #6 - .27. The kit indicates that there are six inserts which I have but there was no #5 which I'm guessing would be for the 6.5. I used the #4 - .25 and guess that its OK because bullet seating is a relative measure. Once I figure out where the bullet touches the lands w/ the #4 insert and keep the same setup for determining seating depth for the right jump I'll be OK. Just odd that the 6.5 is not part of the basic kit.
 
They don't go by caliber especially because in the same caliber bullet shapes with vary thus requiring possibly a diff # for the same caliber with a diff bullet. I have never seen that but it wouldn't shock me. I mean it is supposed to be the same since we are talking about where it touches the rifling. But I check each type (brand and type) with an OAL gauge and get different numbers for each bullet. So I imagine there could be a cal where a VLD could use a diff size than something else.

I use .250" as well. But I had the hornady kit and ended up buying one that I like better.

https://www.amazon.com/Bullet-Headspace-Comparator-Derraco-Engineering/dp/B0CJC5JQ5V/ref=sr_1_4?crid=54N6Q3EPKEVT&dib=eyJ2IjoiMSJ9.685QXpG1G3ot5u67ysa_fSJf8Jq5C9khtzbyUfErrYU_k6YzvWb6P84Z4l8L09tvc4DqhAhSPlnKuXt0GLnPyqIdXOhYA3Nfiis7i-_z3NTG_wseO_xCPFPjUI7fuGdiSIRnc-UEt3nk9XUVrp_xS7awGgrMa_CxeZ-rlSQAX33GM7fF7gJnmTMZZiQ__q5e1V4zzAWMEl5CT0ZS0JTi26KE32c-xLoltTGVO070Q1XTdElp2IHdCoG1kxUaFyeWYQAVveZH_RS5rDOwXKptY6C5kpOk_Ciem1Ckv7N5HR4.BWvrU5QqO8MBHKYwgZ24_pdWUs2lm9kxfpr2guvaO0E&dib_tag=se&keywords=bullet+comparator+kit&qid=1722949869&sprefix=bullet+compa,aps,79&sr=8-4
 
It is odd but yes, #5 is for the 26 caliber stuff and has to be gotten separate
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With the #4 your actual measurement will probably just give you a tiny bit of jump since it’s technically measuring a touch early on the ogive.
 
With the #4 your actual measurement will probably just give you a tiny bit of jump since it’s technically measuring a touch early on the ogive.
The bullet would be the same place in space with regards to chambering. Just measured with a different relative dimension, measured at a different point on the bullet.
The issue with that is variance in the bullets themselves but likely not a huge issue.
 
I am beginning to load for 6.5 CM. My Hornady bullet comparator kit does not have an insert for 6.5 bullets. They have a #4 - .25 & #6 - .27. The kit indicates that there are six inserts which I have but there was no #5 which I'm guessing would be for the 6.5. I used the #4 - .25 and guess that its OK because bullet seating is a relative measure. Once I figure out where the bullet touches the lands w/ the #4 insert and keep the same setup for determining seating depth for the right jump I'll be OK. Just odd that the 6.5 is not part of the basic kit.
You guess is correct and you'll be just fine using that comparator. After all, it is just a "comparator". As long as you're using the same comparator to find the difference between the measurement when it touches the lands and the CBTO measurement for your seating, that difference is going to be the same with just about any comparator.
 
Best thing you can do is take all that hornady comparitor stuff, and throw it in the garbage.

Then go to SAC and buy their bullet and shoulder comparitors. You will get much more reliable and consistent readings.
 
Best thing you can do is take all that hornady comparitor stuff, and throw it in the garbage.

Then go to SAC and buy their bullet and shoulder comparitors. You will get much more reliable and consistent readings.

I'm a big SAC fanboi, have several of their dies, barrel vice kit, etc., but I actually like the Forster datum dials a bit better. I have one Mitutoyo set up with each dial.


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