I've done some tests with Accu-bonds this summer and wasn't overly impressed with them. Scirocco, I found, have better weight retention. Swift A-Frame, oddly enough, has probably the best weight retention among most hunting bullets.
I shoot a Browning ABolt II composite stainless stalker topped with a Bushnell Elite 4200 2.5 x 10 x 40 mm on Weaver see - through mounts with Williams open sights chambered in 7mm Rem. Mag. Scope zeroed at 350 yrds and sights at 100 yrds. I only shoot Winchester Supreme 165 gr. Accubond CT and I'll tell you I get sub MOA results up to 250 yrds. I switched from Winchester Supreme Nosler Ballistic Silvertip 150 gr (which also shoot great) At 394 yards, on my particular rifle, I still get 1.625" groups, in which I think is capable of dropping any big game. Although I must tell you, it's not just the rifle but the shooter. I shoot my rifle quite regularly and have built confidence in the rifle and quite comfortable with it.
Anyone who shoots a sabot bullet has had the problem with loading the next round with a dirty barrel we have all struggled with it.
Between muzzleloader shots I have done some research and testing on my own to find out what works for me for the next shot. I have been using a product called bore butter and when the muzzleloader is just sitting around I leave it caked in the barrel for protection. Have also found that if I lube my sabots with bore butter they really slide nicely down the barrel....