V crown R - was not just a proof mark for English firearms, but was a mark that denoted that the maker was a supplier to the Royal Family - in this case the family of Victoria Regina aka Queen Victoria (in her fathers time it was G crown R). Makers of all kinds of goods including clothes, boots, hankies, etc. used the mark upon becoming a supplier of goods to the Crown. As a firearms proof mark it meant that the firearm had been proofed at one of the "Royal" proof houses.
When we see the term Dirk one generally thinks of the long taper bladed, single edged Scottish Dirks, but the term was also used during the 18th and 19th Centuries for various types of knives including Naval Dirks which were built in different styles: saber style with a single edged and curved blade, a double edged dagger, and later when they became more of an accoutrement rather than a weapon, very fancy dress types were made in several blade patterns. Whether a knife had two edges or a single edge did not necessarily determine the usage of the term dirk.