It would be nice to know what the velocities are in a SAAMI-spec test barrel. That is about the only way to know if your barrel is one of the "fastest" or if, instead, it is somehow producing higher-than-SAAMI pressures to get the higher velocity.
There is a table of velocities for thirty-one .357 Magnum barrels, each with three different bullets/loads in Speer Manual #14. I am not going to try to type it out here, but for the 9 revolvers with 6" barrels, the velocity spread was 1277 to 1603 fps for the 125 grain bullet, 1142 to 1417 for the 140 grain bullet, and 1002 to1284 for the 158 grain bullet. The 10" Contender barrel gave about the same velocities as the SAAMI test barrel, but each is a sample of one, so that may not always be true in other guns. An 8-3/8" S&W (which is about a 10" total barrel length with a gap) gave 1501, 1342, and 1221 fps for the three different bullets. So, it was not as fast as the fastest 6" barrel, and substantially slower than the SAAMI barrel.
So, from that, I would say that you Redhawk probably should not be exceeding the velocity of the same round from a (new) 10" Contender barrel unless it is exceeding SAAMI pressures.
Is there anybody here who has data for the OP's loads in a 10" Contender barrel?
The caveat is that pressure-vs-time curves for revolvers and test barrels apparently look substantially different in shape, based on some earlier experiments by Speer where they instrumented an actual revolver. So, just about every comparison that we can make is already "apples-to-oranges."