Ultima-Lube II Bore Cleaner will remove the toughest of copper fouling. Unlike ammonia based cleaners, Ultima-Lube II Bore Cleaner will not etch or hurt the metal of the bore and there is no need to neutralize Ultima-Lube II Bore Cleaner as is necessary with ammonia based products. Ultima-Lube II Bore Cleaner contains no synthetics and has been extensively field tested and is proven to improve accuracy.