When a reline is done, the entire barrel is lined, including the chamber area.  Therefore, it needs rechambered, and you can chamber it to whatever you want.   

Therefore, the dimensions of the current chamber are irrelevant.

Now, my opinion:  The standard .22 hornet reamer is too large in the neck, and that leads to the short brass life experienced frequently with the hornet.   

I'd either use a custom reamer spec'd closer to brass size, or chamber to the K hornet, which doesn't have that problem.

I don't think the K hornet has any particular performance advantage, but it does have a longer brass life advantage.

dave

It should be obvious that I am not a gunsmith.  I would like to purchase a older low wall and have the work done.  I have seen some that are in 22 WCF and some in 25 WCF That I am interested in.  The 25 WCF Might be a good candidate to change to 25-20.  Would it be possible just to change the chamber of a 25 WCF to 25-20 without a complete reline?  Is it necessary to change the caliber markings on the barrel to comply with the federal government's laws?

JCHannum wrote on Oct 1^st, 2013 at 10:16am:


Assuming it's not a 25WCF made prior to about 1893-4, in which case it's a 25-20 SS.