Got out and shot my new ladder load today with the EGW sizing die. It was a little chilly but sunny and fairly calm. I shot all these at 10 yds off a rest and did try to shoot them accurately.
I saw the power factor drop about 2 (velocity dropped ~10 fps) from the last time I ran a ladder load. It was about 20 degrees colder this time around...
I saw about the same accuracy at the same velocities from before the charge that showed the best accuracy was a little higher (given the velocity drop due to temp). I didn't see any efficiency gain from the higher bullet tension.
The four groups from the ladder (4.4-5.0) start at the bottom left and go clockwise around the target. Take note of the middle group, that is my Gold Dot SD load and is a 10 shot group pushing 165gr Gold Dot ~1160 fps (192 PF) out of my TSO! Stellar group!
Same as above just a replicate set of groups. The center group is the same Gold Dot load shot out of my newly acquired 40 upper mated to my SP01 tactical frame (can swap it out for the stock 9mm slide). It was only pushing the gold dots ~1110 fps (184 PF). Also a stellar group!
It is interesting that the 5.0 groups are so poor compared to the 4.8 groups. It's unfortunate as I really should be running about 170 PF for USPSA. Since I shoot mostly at my local club I choose to shoot the 4.8 load as it is much more accurate (I repeated this several times now and it doesn't appear to be a fluke). It's just barely over the minimum power factor but we don't ever chrono loads at my club. As the temps climb it will increase and give me a little bigger buffer.
Bottom line I don't have to alter my charge given the increased bullet tension of the EGW sizing die. I was sure I would gain some efficiency but the chrono doesn't lie! These cartridges don't setback with the EGW die, problem solved!
Cheers,
Toby