Socialism requires that the state control the means of production. Sanders isn't anything close to a socialist:

why Sanders is describing himself to the American electorate — of all electorates — as a 'socialist' or 'democratic socialist' isn't clear. His economics are Keynesian or Galbraithian, in common with mainstream parties of the left in the rest of the west — the Labour or Social Democrat parties. Surely 'Social Democrat' would be a more accurate and appealing label for the Sanders campaign to adopt. While Sanders claims to admire particularly the Scandinavian model, he neglects to point out that a characteristic of all social democracies is a low defence budget, reflecting not only a degree of anti-militarism, but also social spending as a priority. Beyond tinkering, though, Sanders has no appetite for significantly cutting the Herculean defence budget or criticising imperial adventures. His urging for the World's most authoritarian country, Saudi Arabia, to assert a stronger military presence in the Middle East is a bizarre position for a social democrat to hold. These odd clusters of attitudes are reflected in our placement of Sanders. Domestically the man is an undoubted progressive — not the least for his courageous attack on corporate campaign funding.

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"...Yet while Mr Sanders has built his campaign on a jeremiad against wealth inequality and corporate greed, he isn’t, properly speaking, a socialist—or even a democratic socialist. The better term encapsulating Mr Sanders’ positions is “social democrat”, a label that jibes with his rather mainstream embrace of “private companies that thrive and grow in America” and belief that “the middle class and the working families who produce the wealth of America deserve a fair deal”. To clarify matters, Mr Sanders flatly disavows the very heart of socialism as defined by Karl Marx: “I don’t believe government should own the means of production”, he says."

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You might also check out this article. http://www.dailypublic.com/articles/03092016/sanders-not-so-far-left-not-so-far-out