The Dong GongThe Dong Gong SR500 Rifle Rated Steel Gong Target System The Dong Gong from Defense Targets is a 3 8" SR500 rifle rated steel gong target built for shooters who want instant, satisfying feedback on every hit. The strike face has a distinctive profile that tends to raise eyebrows at the range and then raise even more when people hear how hard it rings. Cut from higher hardness SR500 steel that outlasts standard AR500, the gong delivers a resonant ping