Out of 192 Needhams in the database, there are 34 known to have the hole in the center position and 65 are known to have the hole in the end position.
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Hammer #132 has two holes in the breechblock. At some point in the assembly of Needhams, it was found firing pins were breaking. A change in the firing pin was made and a new location was found for the firing pin retaining screw. Hammer #132 up to now has been the only one found with both holes in the breech block and was thought to be an anomoly. But now a second one has been found.
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I don’t have the hammer number yet. As can be seen the screw itself is now in the first hole. This tells me the center location for the firing pin screw was the original position and the the hole close to the end is the improved version. The most numerous Needhams found today have the hole in the end position.
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