Grendel here is bolt-action, CZ 527. I assume you're having trouble with the reloads cycling an AR action. I couldn't be of specific help on that but you could try the 6.5 Grendel Forum. If you're just looking for good loads, we shoot 90 grain Speer TNT because they're accurate and affordable. We'll hunt with 100 gr. Barnes TSX or TTSX. With the TNT's, 7 to 8 grains of Trailboss is a soft load. It's a heavier bullet than a .22 but there's still similarly no unpleasant recoil. H335 loads go up to 31.7 grains. I've got one boy doing well shooting 30.5 grains. I've read and do believe IMR 8208 XBR is the fool-proof powder for Grendel. It's very consistent across temperatures and it's been reported to have a fairly wide window of charge weights with low SD. Reloader 15 is more old-school but hard to go wrong with.
Back on topic, it sounds like you have a good thing going with your boy. He's still young and he'll grow into your other guns and then you won't be able to make him go back to being little again. You'll just have to wait for grand kids. So enjoy it while you can.
Back on topic, it sounds like you have a good thing going with your boy. He's still young and he'll grow into your other guns and then you won't be able to make him go back to being little again. You'll just have to wait for grand kids. So enjoy it while you can.