Naval News reports BAE has delivered their 50th 57 Mk110 gun system for use on US warships. In this case, that gun will go to a US Coast Guard Cutter, almost certainly OPC #3 or #4. Significantly the first US Mk110 installation was on USCGC Bertholf, commissioned Coast Guard Day, 2008, three months before the first Littoral Combat Ship, USS Freedom (now already decommission).
Fifty guns is really not a lot compared to the number of Oto Melara 76mm or the 5″ Mk 45, but it is on a lot of ships, and the fact that it is expected to equip 20 new FFGs and 25 OPCs in addition to, still yet to be delivered NSCs and LCSs, seems to guarantee long term US Navy interest in the system. Current plans call for a total of 87 ships equipped with the Mk110, 51 Navy and 36 Coast Guard (excluding the first four LCS which are being decommissioned).
I still think, because of the Coast Guard’s missions and the lack of alternative anti-surface weapons on cutters, that our large cutter should have 5″ Mk45 weapon systems (even if only recycled 5″/54s). After all, any improvements you could make to a 57mm round, you could also make to a 5″ (127mm) round, but it is encouraging to see new more capable and more accurate rounds being developed for the gun we do have.