Definitely a Carcano bolt. This is an earlier version M91(93) Carcano Moschetto "cavalry carbine" although there was really no such thing, just that it was the 1893 carbine version of the long rifle introduced in 1891. Early in that it has the adjustable rear sight. Later models had a simple fixed V rear notch. Most likely in 6.5 Carcano. Assume bottom of magazine is open. Earliest versions had a hexagonal barrel in front of the receiver, like my 1901. Then round with the adjustable rear sight, then round with the fixed sight.
Crown RE is Italian military like my 1937 Beretta. No date or Roman numerals (anniversary of Mussolini’s rise to power?)
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