with a proper sight picture (reccomended by the manuf.) what distance is the 3" fixed sight gp100 sighted for???
Probably 25-yards with 158gr .357 Magnum loads. 25 yards is the most common "zero" range for handguns, and they will be regulated to whatever the most common standard loading is for the chambering. Meaning your .357 Magnum is not zeroed for .38 Specials.
is there a special technique for longer range shots with a fixed sight?? does it come down to mostly using the front sight???
Technique: FRONT SIGHT, TRIGGER SQUEEZE. That's it, shooting is nothing more complicated than putting the front sight on the target and squeezing the trigger in such a way as to not move the sight off target. Watch the front sight hard. If you're not seeing the orange ball of burning gas from the shot, you're flinchin and not focused on the front sight enough. Try wearing ear plugs under ear muffs and shoot light .38 Special loads at 5-7 yards for a while to get the hang of it.
You can also dry-fire your GP-100 in the basement. Make sure there is no live ammo in the vicinity and check that your revolver is empty at least twice, make sure it is EMPTY. Then pick a spot on a wall in a safe direction, line up the sights and squeeze the trigger. Focus on technique, front sight and make sure you press the trigger to the rear, not to the sides, straight back. This has the benefit of no recoil masking any flinches you may be doing.
i doubt that it is a great distance or the bullet mass would make too much difference.
With handgun rounds it is recoil that makes the difference in where the bullets impact. Heavier rounds impact higher because they kick harder and flip the muzzle further. Contrary to popular opinion, recoil starts as soon as the bullet begins moving out of the casing. If you lay your revolver on a flat surface on its sights, you will see that the barrel points down in relation to the sights.
also...what is the benefit of adjustable sights outside of target practice (something that isnt moving) or shooting a stationary animal (with little wind...somethign which can vary from second to second anyway)??
At handgun ranges, the benefit is being able to zero to a particular load or for a particular shooter. Also, adjustable sights for revolvers tend to give a larger, "better" sight picture for many shooters (me included). You won't be playing with the adjustable sights constantly anyway. Most shooters zero them for their favorite load/range and then leave them that way.
also, is the 125 gr bullet the most used/produced in 357mag loads???
Possibly. It is the load that generated the .357's reputation as a fighting round. I prefer to use 140-158gr loads, but I also reload my own ammo and find the 140gr Hornady to be one of the most accurate handgun bullets I've ever tried.