Re: Reticles on frontr rear focal plane, why?
Express, just to be sure we all are speaking the same language: A forward or 1st focal plane reticle magnifies with the tgt so that both maintain same relative size, ranging aids or holdover marks are accurate at any magnification. With a rear or 2nd focal plane reticle only the tgt magnifies so the reticle is relatively smaller as magnification is increased. Is that also your understanding of the two reticle locations?
If not a 1st plane reticle, then give me a fixed magnification scope. I have the IOR 2.5-10x with illum MP8 in the 1st focal plane on my .300WSM. With my SMK190 load sighted in at 750 yds I can use mil hold-unders regardless of magnification. At 4x I can take out nuisance stray cats at 50 to 100 yds by holding 5 mils low. If I am looking for feral hogs at long range with the scope on 10x and my quarry appears in the shooting lane at 100 yds then the same -5 mil hold is valid. POI shift a magnification is changed is lessened or nonexistant with a 1st focal plane scope. The poster is absolutely correct that stated that the mil dot reticles in many 1st plane scopes are too thick to allow adequate precision for many situations. However the MP8 thin lines are only .05 mil thick. Judging by the 16x IOR MP8 I believe even a 6-24x 1st plane scope could be usable with that reticle design.
If I must assign an advantage to the 2nd focal plane reticle it is during low light close range work at low magnification. Another advantage only valid for magnifications that approach or exceed 20x with the previously mentioned overly thick mil dot patterns is that a 1st plane reticle would likely obscure too much of the target. That is also the reason that in many high magnification variable magnification mil dot scopes the mils are 1 milliradian at 10x.
[ 03-31-2004: Message edited by: RuffHewn ]
Rapid fire is the crutch of an incompetent marksman. ONE SHOT, ONE KILL