Historical context of late Ketland lock

[Mike C]

What is the earliest date that a late Ketland style flintlock might have been used on a Penn. rifle. I am considering building a JP Beck with wood patchbox and wonder if a Chambers late Ketland would be correct.
Mike C

[Lucky R A]

J.P. Beck usually used a rather small lock.  The Small Siler is a much more correct lock than the late Ketland.  Stan Hollenbaugh makes a lock that is an exact match.  Stan's lock was first made by Robt. Ditchburn, who allegedly made the masters from an original J.P. Beck lock.

[Acer Saccharum]

Stan's locks are very nice.

[D. Taylor Sapergia]

Agreed Tom.  I'm using one right now (after lots of filing) for a A. Verner companion pistol for my rifle.

[Mark Elliott]

English trade locks like the Ketland were mostly used in predominantly English (i.e. Southern) areas.   There was a very strong Germanic influence in PA and locks of Germanic design are usually found on PA guns.   The construction and architecture of German vs English locks is very different, the main difference being the shape and construction of the pan.   Pans are rounded and integral on English locks whereas they are squared off and separate pieces on Germanic locks.  As others have said,   the Siler, Chambers Golden Age, and Ditchburn locks are more appropriate on PA rifles.   

That said,  the outer limit for the Chambers Late Ketland is 1800-1810.    After that,  the locks got much smaller.    You would be looking at one of the Durs Egg, Manton, or Ashmore locks for 1810-1830.    Dixie Gun Works used to make some very nice little late, English Design,  flint locks if you can get one.