Browning .22 Semi auto
"I've taken it apart and cleaned up the block and firing pin. The gun doesn't appear to have been shot very much."
O.K. People, pay attention. I am assuming that the Browning Semi-Auto you are talking about is the one that loads through the stock.
The Browning semi-automatic headspace can be adjusted. Most of the time, when someone takes it apart, and they take the fore-end off the barrel, they fiddle with the threaded ring at the back of the barrel. This changes the headspace, either moving the barrel in or out. This part is called the "barrel adjusting ring", by Browning.
This threaded ring is what governs the headspace. If it is moved too far BACK then you get light firing pin strikes, because the barrel is moved too far forward.. If too far FORWARD, the bolt does not fully close into firing position, because the barrel is too far back into the receiver.
I have bought several Browning semi-auto .22 rifles because of this. All it takes to make them useable is to adjust the headspace with the threaded ring. If you are getting light firing pin strikes, the barrel needs to be moved back slightly into the receiver. Go slow, about 1/8 turn at a time, then check the functioning by firing the rifle.
For you Browning Semi-auto .22 owners, do not take the fore end off your rifle if it is working all right.
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