Rifle Scopes 1st focal vs 2nd

Cal Taylor

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Minuteman
Feb 17, 2011
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I had a guy try to explain to me that one of the benefits to a FFP scope is that the point of impact is less likely to change with a power change. Or that point of impact is more likely to change on a second focal plane scope if you were to change the power from say 10x to 20x. This makes no sense to me as both reticles stil have to be housed in the erector tube so that they can be adjusted correct?
 
Re: 1st focal vs 2nd

Search function has the answer you are looking for.

Im a nut shell..

Your POA will not change with either a SFP or FFP (well it shouldn't if you have a decent optic)

SFP- Reticle will stay the same size as you change magnification. Which means that you can not count on the reticle for holds/ranging unless you know the half power or so on...

FFP- Reticle size will change with the magnification so that it subtends correctly. You can range/hold at any power.
 
Re: 1st focal vs 2nd

<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: BOLTRIPPER</div><div class="ubbcode-body">we make no comments to them that do not complete a profile </div></div>

Sorry Bolt lol, was typing when you posted this.
 
Re: 1st focal vs 2nd

Yes... But on FFP scope the reticle doesn't grow... it remains constant with the magnification. Where a SFP scope only appears to be constant, it actually gets bigger and smaller, depending on where in the erector it is "correct". A simple test of this is in FFP scope a target that is 1 mil tall, is always 1 mil tall...No matter what the zoom. Where as SFP 3-15, that is correct @10x, the target is 1 mil tall only at 10x. On 5x it is 2 mils tall, and on 15, only .5mil.
 
Re: 1st focal vs 2nd

Not sure what this guy was basing his experience on. Mine is with Leupold, Nikon, NightForce, Sightron ...

Maybe your guy has his experience with BSA or ATN.
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Re: 1st focal vs 2nd

Added a couple things to my profile, but not sure what your looking for boltripper. He was talking about higher end scopes as far as I know. I understand the purpose of the FFP as far as using the reticle or mils for ranging, but can't see where it would have anything to do with a point of impact change.