I have been reloading .40 S&W since shortly after it was first introduced, about 20 years now. I have loaded thousands of rounds, all brands of cases, Lead, Jacketed and Plated bullets, and have never seen what you are describing! Pictures would help, but the situation makes no sense as you describe it.
Two thoughts:
1) Are your Remington cases .40 S&W originally, or are they 10mm trimmed to .40 S&W length? If they are trimmed 10mm you can't do that! Internal taper will cause what you describe.
2) As suggested, seat and crimp in two steps, or at least to set the crimp properly. If you are using a taper crimp die start by backing the seater die out 2-3 full turns. Place a ready to load case in the shell holder, run the ram up all the way, then screw the die down until the crimp just touches the mouth of the case. Back the die out 1/3-1/2 turn and set the lock ring. Seat a bullet in a charged case and seat a bullet to the desired/specified LOA in several cases (you might need them). Using these cases, back out the seating stem, release the lock ring, run a loaded case into the seater and turn the die down until it touches the mouth of the case. Lower the ram, turn the die in 1/3 turn and then crimp. Measure mouth diameter compared to about 1/8" down the case. Continue to screw the seater down, crimp, and measure until the case mouth is .002-.003 smaller that the case body just below, then stop, and set the lock ring. With the cartridge all the way up screw the seating stem down snug against the bullet. Take another loaded case and seat and crimp in one step, measure the LOA. If too long adjust the seating stem down a few thousandths until length is correct again. Then set the lock ring on the seater stem. You should now be ready to seat and crimp that bullet style in one step. If you do it just as I have described whatever problem you are seeing will go away, guaranteed.
Note: If you are using mixed brass, as it sounds you are, you will experience a different amount of crimping effort between brands. Be sure to always move the press handle all the way to the stop when moving the ram up, and for all operations.