An efficient Medium access control (MAC) protocol is an important part of every wireless system. It prevents multiple devices from accessing the channel at the same time by defining rules for orderly access. Due to the fact that wireless networks have received enormous popularity in the last 10 - 15 years, number of users in these networks increased dramatically. Thus, support of large user population for modern MAC protocol is not an option anymore but a necessity, especially for dense Wireless Sensor Networks (WSNs). This work proposes a novel random MAC protocol for wireless networks named BCSMA/CA that can provide high channel throughput for very large number of users. The main idea of the protocol is based on the absence of backoff intervals where the channel is idle and using this time for active collision resolving. By presented analytical model and means of simulation, performance of the proposed protocol itself as well as in the framework of 802.11 Distributed Coordination Function (DCF) is explored. Corresponding comparison shows that 802.11 under BCSMA/CA is more suitable for applications where number of users is large compared to the traditional DCF approach.