Ballistocardiography (BCG) describes the measurement and analysis of ballistic forces that are evoked by the heart's movement and propagated to the surface of the body. Although there are several research groups focusing on BCG, the understanding on general BCG signals is still limited, as existing studies only consider a small number of subjects and insufficient measurement setups.This paper presents first results of our ongoing study to collect BCG ground-truth data. We present a custom hardware implementation for both, high data quality and simultaneous ECG reference measurement. In a large-scale study we currently collected more than 10 hours of BCG data from 34 subjects including BCG in resting position as well as under physical stress. In addition, related biometric data are collected to enable comprehensive investigations. We plan to provide access to the data for interested researchers.