Space-time finite element methods for dynamic frictional contact problems are discussed in this article. The discretization scheme is based on a mixed formulation of the continuous problem, where the Lagrange multipliers represent the contact and frictional stresses. Using piecewise d-linear and globally continuous basis functions in space and time to construct the trial space for the displacement as well as the velocity field and combining it with a test space consisting of piecewise constant and possibly discontinuous basis functions in time, a space-time Galerkin method is constructed. The Lagrange multipliers are approximated by piecewise constant functions in space and time. Several methods to ensure the stability of the Lagrange multipliers are proposed and compared numerically.