Although this is maybe not what you want to hear, but there are light-years between the commercial solvers CPLEX and Gurobi on the one hand and open source solvers on the other hand.
Nevertheless you can be lucky and your model works fine with GLPK, Coin or the like, but in general open source solutions are way behind the commercial solvers. If it was different, no one would pay 12.000$ for a Gurobi license and even more for a CPLEX license.
In the past years I have seen many, many models that were just to difficult for the open source solvers. Believe me...
It's not so much a question of size, but of numeric difficulty.
