1873 Dutch Beaumont-Vitali M1871/88 bolt action magazine conversion

Neat little gun. One of Dad's again, I don't know much about it. Marked P. Stevens Maastricht, then factory converted in 1891? Caliber not marked, but research suggests it is 11.3X51R caliber. Marked 1873 on barrel and 1891 on buttplate (conversion date?). Heavy 21.5" barrel.