Experience w/ Hornady Headspace Comparator?

[Howland]

Yes I am aware that CIP DRAWINGS do not use the SAAMI headspace drawing conventions. However I have an EXCEL spreadsheet that does the trigonometry to convert the CIP numbers into SAAMI format numbers.

Please enlighten me on the definition of CIP.

One cartridge I will be working on is the .338 Lapua Magnum. My brother picked up an FN Ballista and wants to get into reloading (Hornady A-MAX 285gr. factory ammo is $79.99/box at the LGS!) so I'll be teaching a newbie. FWIW, reloading is the only firearm area he is a newbie at.

The .338LM SAAMI drawings show a headspace dimension for the chamber but not for the cartridge. Many dimensions on both drawings are highlighted, indicating they "have no corresponding CIP analog." I'm not sure what is meant by that. The chamber drawing indicates headspace is .476" at 2.2530" from cartridge base. Also, the shoulder angle is slightly different between the cartridge and chamber drawings. 19°59'54" for the cartridge, 20°00'23" for the chamber. The .308Win drawings show an equal 20° shoulder angle.

With the comparator set, M1A1 fired brass shows 1.635". Now I'll have to take the PA10 out for break-in and get some brass from that for measurements and then some from my brother's RPR. If there is more than .001" between the three, I see a set of Redding Competition Shell Holders in my future, thanks to @philip brousseau for the tip.

 

[dcali]

CIP is the European version of SAAMI. Very annoying folks, as they insist on using the metric system.

 

[ireload2]

CIP= COMMISSION INTERNATIONALE PERMANENTE
Which is the European standards organization for small arms ammo and chambers.

To look up your .338 LM go to CIP homologation.
Pick the rimless rifle cartridges tab.
Then go to page 7 or 8 for inch designated rounds. Pick EN for the English version.
The two different shoulder angles were calculated by someone based on rounding errors I suspect. The difference is so small as to be unmeasurable.

"NO CIP ANALOG"
SAAMI and CIP use 2 very different dimensioning schemes to locate the shoulder so they do not share many dimensions that locate the shoulder.
If you are good with trigonometry you can convert CIP dimensions to SAAMI format numbers.
SAAMI dimensions are more practical for gaging ammo and chambers. CIP numbers tend to be more theoretical and less gage design friendly.

Let me know if you have more questions.

Please enlighten me on the definition of CIP.

One cartridge I will be working on is the .338 Lapua Magnum. My brother picked up an FN Ballista and wants to get into reloading (Hornady A-MAX 285gr. factory ammo is $79.99/box at the LGS!) so I'll be teaching a newbie. FWIW, reloading is the only firearm area he is a newbie at.

The .338LM SAAMI drawings show a headspace dimension for the chamber but not for the cartridge. Many dimensions on both drawings are highlighted, indicating they "have no corresponding CIP analog." I'm not sure what is meant by that. The chamber drawing indicates headspace is .476" at 2.2530" from cartridge base. Also, the shoulder angle is slightly different between the cartridge and chamber drawings. 19°59'54" for the cartridge, 20°00'23" for the chamber. The .308Win drawings show an equal 20° shoulder angle.

With the comparator set, M1A1 fired brass shows 1.635". Now I'll have to take the PA10 out for break-in and get some brass from that for measurements and then some from my brother's REPR. If there is more than .001" between the three, I see a set of Redding Competition Shell Holders in my future, thanks to @philip brousseau for the tip.