Why would you mix different rounds in your revolvers like that? It's really not a good idea IMO. Mixing different bullet weights, bullet companies and velocities will make it very hard to achieve accurate bullet placement. In reality bullet placement is much more important than the bullet you shoot. When under pressure it's hard enough to shoot well but with all the variables you are forcing on yourself I would find it very difficult to place my shots accurately.
Model 640 (38): First 2 up are BB Standard Pressure 158's, followed by 3 BB 158 +P's.
jad0110,
The DoubleTap 125gr ammo feels just about the same as the Speer 135gr ammo or just a little more recoil. When I ran them both over a chrono the DoubleTap ammo was faster. When I carry a JHP round it's usually DoubleTap because of the price. Since they both use a Gold Dot bullet why not pay $26/50 rounds instead of $21/20 rounds of Speer Ammo. I haven't shot either at night or Dusk so I can't tell you if the flash is different.
As for the FBI load, I use Remington R38S12 rounds and the felt recoil does seem a little higher but that's to be expected when you're firing a 158gr projectile compared to either a 125gr or 135gr bullet. After several years of carrying either the Speer SB round and more recently the DoubleTap round I think I like the FBI load better and will be carrying that from now on. I also like the fact a 158gr bullet shoots POA=POI on a fixed sight S&W revolver.
Hope this helps a bit...
There is another added advantage of carrying JHP rounds as reloads instead of the lead rounds. A continuing knock against the FBI round is the lead is soft so when carried in your pocket for a while the hollow point tends to crush over or close. If you decide to carry the DT rounds as reloads that would eliminate the possibility of bullet distortion. (I hope I explained that well enough)But if I like the FBI load and do equally well with the DTs, I may well load my 642 with the 158s and carry the DTs as reloads. Those smaller, slicker 125 grain JHPs are easier to line up with the charge holes than the larger 158 grain LSWCHPs IMHO.