Can someone please tell me why there is a machined slot on the threaded section of some bolt heads. I have one bolt head with no slot and one with a slot.
Thanks.
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Can someone please tell me why there is a machined slot on the threaded section of some bolt heads. I have one bolt head with no slot and one with a slot.
Thanks.
The design of the bolt head and striker changed,
The 'slot' version is the older design and you will find that it cannot be screwed into a later bolt head - it feels like its a 'taper thread' and gets tighter and tighter until it jams.
Original MkI SMLE was designed so that the bolt could be disassembled without tools. The striker had a lug on the front of the collar and the groove in the bolt head allowed it to be used as a wrench to unscrew the striker. This system was soon abandoned but groove in the bh was retained to allow use of old stocks of strikers.
Here is a picture illustrating the differences in early and later bolt heads and strikers.
Attachment 112104
Thank you to all who kindly replied to my question.