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Scope stuff

JustjumpJustjump Member Posts: 644 ✭✭✭✭
Need a quick but accurate scope education. FFP, SFP what are they talking about? advantages disadvantages? Are First Focal PLane scopes a specialty tool? And as an aside. What the heck is up with all the lighted reticles these days. I have some but really think they are unnecessary for the most part. This may be the wrong place to post but...

Comments

  • JustCJustC Member Posts: 16,056 ✭✭✭
    edited November -1
    front focal plane reticles will grow in size as the magnification is increased and visa versa. This allows them to subtend the same amount of space no matter what power they are set on, thus allowing ranging on any power.

    The second focal plane reticle only subtends the specified amount of distance on the specified magnification.
  • JustjumpJustjump Member Posts: 644 ✭✭✭✭
    edited November -1
    OK I'm a bit slow on this so let me see if I got it. On a Front Focal Plane the reticle will cover the same amount of target no matter the magnification. So the distance between mill dots will be the same at a given distance through the full range of magnification? Is that what you mean by ranging? Or am I just completely lost?

    Its difficult in the Ozarks to find a shot longer than 300 or so yards. I do have a spot here where I can get 700 with a small amount of work. I don't know what qualifies as a long shot But it is sweet when a plan comes together. Just trying to come up with a plan...
  • FrancFFrancF Member Posts: 35,279 ✭✭✭
    edited November -1
    http://www.mil-dot.com/Mil_Dot_Leupold_Engineers.htm
    However- Mil dots vary
    http://www.boomershoot.org/general/TruthMilDots.htm

    As for use in Range finding, one of my mil-dot scopes needs to be set to the fixed ranging power. That dot will cover about a 3.5" area at 100 yards.


    Forgot to add here is a free practice mill dot shooting simulator
    http://www.shooterready.com/lrsdemo.html
  • sandwarriorsandwarrior Member Posts: 5,453 ✭✭✭
    edited November -1
    quote:Originally posted by Justjump
    Need a quick but accurate scope education. FFP, SFP what are they talking about? advantages disadvantages? Are First Focal PLane scopes a specialty tool? And as an aside. What the heck is up with all the lighted reticles these days. I have some but really think they are unnecessary for the most part. This may be the wrong place to post but...


    FFP= First (Front) focal plane. The reticle is on the same focal plane as the target/view. As you increase or decrease in power the reticle grows or shrinks with the target/view. For instance, you see an old car in the distance on low power. As you turn the power up the car gets bigger but so does the reticle. But the reticle remains proportionately the same size to the car as when it was smaller. This is not a specialty tool, it's just more of a European preference. The easy part with these reticles is you never have to worry about where your power is set to use a ranging reticle such as a Mil-dot. The downside of course is you can't use power to range with.
    SFP= Second focal plane. This reticle is on the same plane as your eye. The reticle always stays the same size in relation to your eye, not the target/view, no matter where the power is. The good thing about this scope is you can range using the power of magnification of the scope. The reticle also has a set size at a given power you can range from. In a typical 4-16x mil-dot scope you will find the mil-scale accurate @ 14x. I say typical, that isn't always the case. The reason it isn't the highest power is sometimes you have to back down for mirage or near range of target. It was explained to me by a factory rep as to why that power is commonly chosen. Again, not always the case. Using a standard duplex reticle, you can range simply by pre-measuring distance on your scope at different powers at a given range. Say the lower thin line is 3" @ 3 power on a 3-9x scope and it's 1" @ 9x at 100 yds. Approximately 3 MOA to 1 MOA. Multiply by number of 100 yds. and you get a relative distance. 3" @ 100 same as 9" @300. Say a prairie dog you estimate to be 9" tall stands up and on low power he fits your reticle perfectly. He's 300 yards away. The down side to a SFP is you have to have the power dialed correctly for the reticle to work. Or at least know exactly what your reticle size shows on the power you are at.

    As far as lit reticles, it's become a fashion based on tactical scopes having them. They help in really low light conditions. Problem is IMO, is that most of them are too bright. Even with the red you get temporarily night blindness after looking through one. Also, the typical hunter does not need one. A good light gathering scope will have a good view of the reticle long after shootin' hours.
    But the choice is yours, and they are available.
  • JustCJustC Member Posts: 16,056 ✭✭✭
    edited November -1
    you understand it correctly. With a FFP, the distance between mil-dots or MOA hash marks remains constant no matter the magnification. with e SFP reticle, it only subtends the specified amount, at the specified magnification.
  • JustjumpJustjump Member Posts: 644 ✭✭✭✭
    edited November -1
    Thank you all very much!
    I truly learned something and now have a better basic understanding. Thanks again
  • MobuckMobuck Member Posts: 14,090 ✭✭✭✭
    edited November -1
    The FFP will cover up a small target at high power.
  • sandwarriorsandwarrior Member Posts: 5,453 ✭✭✭
    edited November -1
    quote:Originally posted by Mobuck
    The FFP will cover up a small target at high power.


    No, SFP will cover more of the target at low power. FFP covers the same amount of target no matter what power.

    However, I did sell a FFP Swarovski specifically because it had an extremely heavy reticle. That would have been fine for hunting, but what I wanted at the time was a 'target/tactical' and you can well believe that Swarovski sale did a great job of funding the majority of it.
  • scottsdalepingscottsdaleping Member Posts: 38 ✭✭
    edited November -1
    quote:Originally posted by sandwarrior
    quote:Originally posted by Mobuck
    The FFP will cover up a small target at high power.


    No, SFP will cover more of the target at low power. FFP covers the same amount of target no matter what power.

    However, I did sell a FFP Swarovski specifically because it had an extremely heavy reticle. That would have been fine for hunting, but what I wanted at the time was a 'target/tactical' and you can well believe that Swarovski sale did a great job of funding the majority of it.
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