[astyanax]

Hope their gunsmiths are more competent than their editors.
"Right: Like the 1860 Henrys, the 1873 Winchester rifles included a lever lock to insure the lever remained securely in place. "
"...a factor that really insured the success of the 1873 Winchester rifles..."

[jimt]

Actually, insure was the common American English spelling until the last 20 or 30 years. Ensure is trendy, and a word I don't use unless I'm talking about the old folks drink.