OK, all the good talk about the Marlin Papoose on this and other forums put me over the edge . . . I bought one today. What a pretty piece.

I grew up with guns in Texas. But it has been years since I’ve shot and all the new ammo options are confusing me.

In anticipation of receiving the gun I bought :
100 rounds of CCI CB Long [Conical Ball 22 L LRN – 29 Grain]
100 rounds of CCI Mini-Mag HP High Velocity [22 LR CHP – 36 grain]
500 rounds of Remington 22 Thunderbolt 22 LR Hi-Speed [40 grain lead round nose]

So I get the gun and read the manual. In part, it says they recommend:
CCI Mini-Mag [no details]
CCI Mini-Mag Hollow Point [ no details ]
Federal Classic Hi Velocity
Remington High Velocity [NOT THUNDERBLT]  Their words!!
Winchester Super X High Velocity

What is it about the Remington Thunderbolt that is a problem? Surely a 40 grain round isn’t too much for this gun?

Any help would be greatly appreciated.