Conflicting specs for .45 ACP loads

[JimGun]

On the Hodgdon reloading web page, for a 230 gr L-RN for .45 ACP, using Win. 231, the load should be between 4.3 to 5.3. with the C.O.L. being 1.200”.
In my Speer Reloading Manual, for a 230 gr. L-RN for .45 ACP, using Win. 231, the load should be between 5.1 to 5.6 with the C.O.L. being 1.270”.
First, I would like to know if there is an explanation for the disparity in the loads?
Secondly, what is the effect of the C.O.L. of 1.200” and 1.270”?
Any help would be greatly appreciated

 

[bofe954]

If the bullets are the same length, the cartridge loaded longer would need more powder to achieve the same velocity.

I think I remember 1.250 for 230gr round nose. Bullet shapes can vary. To some extent the shape of the bullet can determine the depth of seating.

The manuals are just reporting what they tested, not necessarily what you should use.