Westley Richards made  many styles of rifles with different actions. I believe that Sherwood is just the cartridge name. Can you narrow it down some or post pictures?

dblgun, that's not a falling block.  It is a tilt or tipping block.  The rifle is made on the Martini action.  Really nice sporting Martinies of this quality are bringing around $1750 on Gunbroker - at least those that are well engraved and in .577/450 caliber.  Those are considered high prices by some, but nonetheless, they are real.  I know, I'm one of the buyers.   

In this caliber, I would guess it is worth somewhat less though the take-down feature and high quality of Westley Richards from the gitgo are always in your favor.   

So, I'll ballpark this and say - if it is .30 cal and it's not a .303 (a popular and favored caliber) - it is worth maybe $1500.   

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This gun also sold for $1750 - I know, I own it
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You might also want to ask over here:
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These guys (and some of them are on this board) know a lot about this type of action and can tell you a lot about them.  Their estimates of values seem mighty low though - given my experience and shopping around.

Brent

Here is a link to an excellent article on the Sherwood (.300 Extra Long)

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