I also seen some increased muzzle rise and recoil when applying defensive rounds which include Sig V-Crown masses, however it wasn’t unmanageable. At it’s release HP was nonetheless underneath the gun from law fit and political pressures of the time and wanted their revised carbine to fly under the radar. https://shaneqixmy.ssnblog.com/38420211/9mm-carbine-no-further-a-mystery