'coaspen' - Upon further examination, your bolt-sleeve is a type of 1892 bolt-sleeve that was altered at the armory to use the later type of Krag safety.

IIRC - Your sleeve 'type' was used on model 1892 Krags that were updated in the early 1900s to 'model 1896 configuration'. Your sleeve accepts the later model 1896 and 1898 'Safety'. A groove has been machined on your bolt-sleeve, so that it retains the spring-loaded pin that is part of the later safety-levers.

photos:#1. Your bolt-sleeve contrasted with #2. an earlier model 1892 type. #3. Parts to look for that should work on your Krag.

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