Lawnboi
WKR
6gt and 6 dasher, you're stuck wirh dbm aics or aw style mags, all 10-12rd capacity. There are zero 5 Rd mags. A creedmoor hawkins hunter mag with the arc/grendel kit installed is a possibility with 6 dasher.
I've heard of some guys running magpul aics pmags successful with the gt, and those could work for 5rds. Neither of these cases will feed bdl style off the feed lips of an action, and wyatts center feed box is designed to run short mags.
6X47 6XC or 6CM, will feed in damn near everything.
You have the Hawkins (they made a standard spacer kit) and AI/primal rights 5 round mag kit available for shorter dasher options.
So far, I have had zero issues with MDT and AI/primal rights kits.
For a tikka Waters makes a 6 round br/dasher mag.