I just checked two boxes I have on hand. There is a visible difference, but not enough to cause pressure concerns - this is strictly my own opinion. It appears that the soft noses may have contributed to the difference in seating depth - possibly the seating plug was for a different bullet nose shape, as the edges on some of the bullet noses are just slightly more rounded than others, and these are not seated as deeply as those with sharp-eged noses. The maximum difference ( as near as I am able to measure) is close to 1/64", but enough to make the cannelure more visible.
The Winclean ammo is intended for indoor range use - it has a "clean" primer, which doesn't emit lead, barium or strontium particles. It also has less flash intensity than a standard primer, and the flash hole in the primer pocket is enlarged to help compensate for this (makes the empty brass very "iffy" for reloading, as it may increase pressures with standard primers).
SAAMI has reduced the pressure limits for .357 Mag. manufacturers, and this is made under the new guidelines, so it is below the 35,000 previously considered max. Put this all together, and I would fire it in an L or N frame revolver, but still not risk it in a J frame. There have been some posts reporting inconsistent ignition with these new primers, so it is definitely NOT carry ammo, and Winchester does not recommend it for PD.
