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Here are my thoughts on the LNL system:
Seating the LNL "special" case can only be accomplished by "ramming it home", and then possibly seated more firmly with a slight twist. It's also possible to seat the case with a light tap on the holding tube. Does this approximate a bolt slamming a case into battery? Probably not. But it should not matter that much, as the case does not compress into the chamber, and can (should) be held firmly in the chamber while establishing the bullet seating depth.
My concern about the LNL lies in a different area, though. I am not comfortable with the Hornady-provided case being used as part the final measurement. That is because it is not a fire formed case, which is what we all end up reloading (past the first loading of new brass). Most of the people I've heard from who've posted their findings have reported some case lengthening, even after resizing, over the factory fresh case length (as measured to the shoulder datum line). This means that the Hornady LNL case will render COAL numbers a few thousandths shorter than if a fire-formed case had been used.
Is this a distinction with a difference? It's difficult to say so, with 100% certainty, but the difference is there, unless you always resize your fired brass to match the Hornady LNL case within .001" or .002".
This is one of the reasons why I've begun using the Sinclair tool, which relies on a fired case for its measurements. Although the case is seated in much the same way as with the LNL tool, it was formed in the target chamber and has a more accurate overall case length (again, as measured to the shoulder datum line).
The only other method I am aware of to determine COAL involves a tool similar to the kit that Franklin Arsenal provides, and utilizes no case at all. It involves a cleaning rod or suitable replacement, a couple of rod clamps, and is used to first measure the face of the closed bolt, and then again to the projectile in the bore. This method, however, does not account for headspace. Again, one can ask if this is this a distinction without a difference?
Any way you stack it, though, choose one method and don't mix your results. When you get your COAL, common practice is to start at least .020" off the lands, and your groups will tell you what the rifle likes. If you find yourself approaching the max COAL, caution should be exercised and pressure/velocity should be carefully monitored.
THAT is my story and I'm sticking to it.
Seating the LNL "special" case can only be accomplished by "ramming it home", and then possibly seated more firmly with a slight twist. It's also possible to seat the case with a light tap on the holding tube. Does this approximate a bolt slamming a case into battery? Probably not. But it should not matter that much, as the case does not compress into the chamber, and can (should) be held firmly in the chamber while establishing the bullet seating depth.
My concern about the LNL lies in a different area, though. I am not comfortable with the Hornady-provided case being used as part the final measurement. That is because it is not a fire formed case, which is what we all end up reloading (past the first loading of new brass). Most of the people I've heard from who've posted their findings have reported some case lengthening, even after resizing, over the factory fresh case length (as measured to the shoulder datum line). This means that the Hornady LNL case will render COAL numbers a few thousandths shorter than if a fire-formed case had been used.
Is this a distinction with a difference? It's difficult to say so, with 100% certainty, but the difference is there, unless you always resize your fired brass to match the Hornady LNL case within .001" or .002".
This is one of the reasons why I've begun using the Sinclair tool, which relies on a fired case for its measurements. Although the case is seated in much the same way as with the LNL tool, it was formed in the target chamber and has a more accurate overall case length (again, as measured to the shoulder datum line).
The only other method I am aware of to determine COAL involves a tool similar to the kit that Franklin Arsenal provides, and utilizes no case at all. It involves a cleaning rod or suitable replacement, a couple of rod clamps, and is used to first measure the face of the closed bolt, and then again to the projectile in the bore. This method, however, does not account for headspace. Again, one can ask if this is this a distinction without a difference?
Any way you stack it, though, choose one method and don't mix your results. When you get your COAL, common practice is to start at least .020" off the lands, and your groups will tell you what the rifle likes. If you find yourself approaching the max COAL, caution should be exercised and pressure/velocity should be carefully monitored.
THAT is my story and I'm sticking to it.
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