Here's what you can fit and whats working well on size 300 Altra in .166
Easton 75 grain match grade size 4, these as ss/AL, they fit perfect with zero sanding, so far the tough and durable.
Ethics .165, .245 Sleeve 75 gn (TI Post/TI Sleeve) a light sanding is needed to install the sleeve, no issues at all. These are the best TI insert I have used so far, only downside is the cost and the shipping and Communication from ethics it's pretty subpar. As far as quality component you'd be hard for us to find better.
Any of the victory half out system will work with the Altras as long as you get the outside diameter correct these outs are decent. They're very economical considering what they cost a 12 pack and they're easily replaced .
The stock components are not my favorite so far however, I must admit they are proving more durable than I originally thought they would be.
I also have an order in from CMI for their four mil titanium outserts and will give them a spin as well
