I think your charge is plenty if the powder is good. The point I was trying to make is that there is a possiblilty that the first few shots might have had the powder contaminated with storing oils. I think 90 gr of T7 is plenty for the 300gr. bullets. The comment about the sabot staying with the bullet too long is interesting. Not sure how that could happen but interesting. I only had some powerbelts keyhole (one 348gr. that went through and elk sideways without even losing the plastic aero-tip when found in the far side skin). That was with too low a charge of a the old goex ascorbic acid based powder that was pretty poor. That was the explanation from CVA. Once the powder was changed to a better one and the charge upped from 80gr. to 90 gr. all the bullets flew straight.