The effect of the compound of glycine-nitrate compositions on the completeness of the formation of solid solutions of barium-strontium metatitanate was studied. It was shown that the decomposition of all examined glycine-nitrate compositions begins at a temperature of 180 ° C, but depending on the glycine content and the pH, it has a different character. The optimal condition for the formation of single-phase products is the volumetric combustion mode, achieved when the content of the reducing agent is higher than the oxidizing agent in the composition. Such compositions make it possible to obtain nanosized powders of Ba1-xSrxTiO3 solid solutions (0≤ x≤0.4) by calcination at a temperature of 550 ° C, as well as to introduce them into composites based on porous magnetic glass, avoiding the interaction between the formed ferroelectric phase and the glass matrix.