What is the difference and when is one better than the other?
1st Focal Plane vs 2nd Focal Plane
- Thread starter Matt Landfair
- Start date
shooters101
OPFOR
While at the last DARC event this topic came up in the OPFOR shack. All I can say about it is 1911 or Revolver!
FFP scopes place the reticle on the same plane as the target, IE the reticle stays proportionate to the target no matter what power magnification it is set on. This allows the shooter to utilize the wider FOV of low power, or the higher detail of high power (or anything in between), yet still use the reticle to accurately estimate range or use holdovers to engage the target.
Conversely, SFP scope reticles are only proportionally accurate at a preset magnification, usually (but not always) at the scope's maximum magnification. This negates the advantages above, as well as requiring an extra step to ensure accuracy. These scopes are usually (but again not always) less expensive than their FFP counterparts.
My $.02, For duty/combat use, FFP reigns supreme and if it is an option it should be used. If your intent is stationary target shooting (F class, Palma, etc.) or the like, then SFP is perfectly acceptable.
Conversely, SFP scope reticles are only proportionally accurate at a preset magnification, usually (but not always) at the scope's maximum magnification. This negates the advantages above, as well as requiring an extra step to ensure accuracy. These scopes are usually (but again not always) less expensive than their FFP counterparts.
My $.02, For duty/combat use, FFP reigns supreme and if it is an option it should be used. If your intent is stationary target shooting (F class, Palma, etc.) or the like, then SFP is perfectly acceptable.
The SFP is perfectly fine for lower power scopes with red dots for CQB/close in work. By having the reticle and dot on the SFP the dot does not get bigger as you increase magnification. This gives you a small precise aiming point at the higher magnification.
This photo shows how small and crisp the red dot is with the SFP Vortex Razor II maxed out at 6X. I carried a S&B short dot 1-4 for years and it was FFP. The dot was so large at 4X that I would have to turn off 5he illumination to make precision shots.
At what point do you need to be jumping into FFP scopes? Any time you have a scope over 8X and you plan on using inline night vision devices. No matter how big and bad your Uber sniper scope is you are going to need to back off your magnification to between 6-8X to prevent overpixelation of the display of your night vision device. So a 16X with SFP is straight fucked because the mills are no longer true and range estimation is no longer possible using the reticle.
This is the exact flaw with the original MK-13 sniper system. The fucking SEALs spec'd Night Force SFP scopes and when Special Forces Sniper Course incorporated the .300 into their program, the night shoots were a fucking shit show.
Thanks a lot Navy.......
This photo shows how small and crisp the red dot is with the SFP Vortex Razor II maxed out at 6X. I carried a S&B short dot 1-4 for years and it was FFP. The dot was so large at 4X that I would have to turn off 5he illumination to make precision shots.
At what point do you need to be jumping into FFP scopes? Any time you have a scope over 8X and you plan on using inline night vision devices. No matter how big and bad your Uber sniper scope is you are going to need to back off your magnification to between 6-8X to prevent overpixelation of the display of your night vision device. So a 16X with SFP is straight fucked because the mills are no longer true and range estimation is no longer possible using the reticle.
This is the exact flaw with the original MK-13 sniper system. The fucking SEALs spec'd Night Force SFP scopes and when Special Forces Sniper Course incorporated the .300 into their program, the night shoots were a fucking shit show.
Thanks a lot Navy.......
I had the same complaint about the original Mk4/PVS 29 combo with the M110. That and no zero stop and turrets without baselines. Glad they are being phased out in favor of the Mk6's.
I posted up something rather lengthly in the last forum, but here go.
For those that do not understand the difference as well as how to tell just by picking up a random scope and finger fucking it-
SFP "Second Focal Plane"- Scope magnification changes the FOV and magnification, but the reticle stays the same size throughout the whole zoom range. This means that the reticle can only be counted on to produce accurate hold overs and mil readings at maximum magnification.
FFP or "Front Focal Plane"- Scope magnification changes the size of the reticle relative to the zoom, therefore the reticle's dimensions stay the same no matter what zoom, allowing for someone to take mil measurements and hold over's throughout the whole zoom range of the scope.
Pro's and Cons
Overall, there are some plus's and minus's to each design and one has to take in to consideration a lot when selecting a scope for professional use.
SFP
Pro's- A second focal plane scope generally has less glass involved in its design, thus it will arguably have better clarity and light transmission. This also makes for a scope that is less expensive. For a shooter who predominately dials his adjustments for wind and elevation this is likely all you need. Hunters and Hi-Power shooters seem to favor these for that reason. That isn't to say that you can't as a shooter figure out the "half" mark on your magnification by a little trial and error and thus making it still usable at lower mag with hold overs. This trick essentially boils down to dialling it down to the exact half way mark and thus doubling your available mils. This takes some experimentation on your part but its a viable technique if you are limited to issued optics and they happen to be SFP (like me).
Con's- Now, from a professional standpoint, I'm not a huge fan of SFP scopes so my opinion may be biased in this regard. The biggest issue from my perspective on SFP scopes is that they are truly limited when it comes to Elevation and windage hold overs, mainly for wind and movers when things get close. Since you have to be at max magnification, anything that is closer then 400m and mobile can be a pain to trap with a 10-12x powered scope, which seem to be the most common SPF max magnifications I see throughout the industry. Anything higher then that IMHO is not terribly useful for the mil/LE precision marksmen as the magnification at the top end becomes a hindrance at close ranges, magnifying every movement and limiting the FOV available. It makes it even more of a PITA when trying to take an accurate mil reading. The best accessory for someone who is limited to a SFP scope is a good LRF.
FFP
Pro's- The FFP scope offers a lot of flexibility for the professional marksmen. You have the choice of dialling or holding over at any magnification distance. This also gives you a much more flexible scope for using forward mounted NV devices like the PVS-27/30. Lets also get something straight. Just because you have 15-27x of magnification doesn't mean you have to use it to make a shot. It just makes the scope more flexible for both shooting and observation This gives a shooter/spotter team the ability to double their firepower and lethality, allowing for a spotting scope to stay in the rear and another weapon system to be fielded, with each person spotting for the other. Rarely have I ever seen the need to go above 20x on a spotting scope to see trace/impact, even at extended distances so I'm not terribly convinced of their usefulness these days. Mirage can make that even worse at extended distance. Again, a FFP gives the shooter a lot of flexibility. It's even better if the shooter and spotter are shooting similar or the same reticles, so the cross talk/chatter is cut to a minimum. Also something to note with FFP scopes- its a huge benefit if your calling your own shots and making corrections to have your scopes adjustments and reticle be in the same value ie Mil/Mil and MOA/MOA. I personally prefer mil's as the math is more streamlined for what I'm used too. This makes for very fast adjustments and shot to shot corrections, and less mental effort to produce a hit.
Cons- First of all, because the design is more complex, the price typically follows that trend. Light transmission can suffer a tad due to the additional glass. Because there are a quite a few different zoom ranges available across the market you also can run in to issues the reticle becoming less then helpful at lower magnification ranges. Some scopes, like the venerable 5-25x Schmidt and Bender PMII have "tunnelling" issues at low magnification. Mine begins at 8x and this is corroborated by other S&B owners. My NF BEAST also tunnels buts closer to 6.5x so not a huge issue. Tunnelling is identified as you dial down your scope and notice that at a certain point, the FOV stops getting wider and you get the visual effect of looking through a toilet paper tube. With FMNV there also is a few issues with regards to magnification. FLIR and FMNV are limited on their resolution. Because their resolution doesn't change relative to the scopes magnification it can render the high magnification range of a FFP scope pretty much useless. This isn't a con so much as something to be aware of if you have access too and regularly use such devices.
In the end, pick what is best for your uses BUT, making the effort to understanding everything about your equipment and how to take advantage of it.
For those that do not understand the difference as well as how to tell just by picking up a random scope and finger fucking it-
SFP "Second Focal Plane"- Scope magnification changes the FOV and magnification, but the reticle stays the same size throughout the whole zoom range. This means that the reticle can only be counted on to produce accurate hold overs and mil readings at maximum magnification.
FFP or "Front Focal Plane"- Scope magnification changes the size of the reticle relative to the zoom, therefore the reticle's dimensions stay the same no matter what zoom, allowing for someone to take mil measurements and hold over's throughout the whole zoom range of the scope.
Pro's and Cons
Overall, there are some plus's and minus's to each design and one has to take in to consideration a lot when selecting a scope for professional use.
SFP
Pro's- A second focal plane scope generally has less glass involved in its design, thus it will arguably have better clarity and light transmission. This also makes for a scope that is less expensive. For a shooter who predominately dials his adjustments for wind and elevation this is likely all you need. Hunters and Hi-Power shooters seem to favor these for that reason. That isn't to say that you can't as a shooter figure out the "half" mark on your magnification by a little trial and error and thus making it still usable at lower mag with hold overs. This trick essentially boils down to dialling it down to the exact half way mark and thus doubling your available mils. This takes some experimentation on your part but its a viable technique if you are limited to issued optics and they happen to be SFP (like me).
Con's- Now, from a professional standpoint, I'm not a huge fan of SFP scopes so my opinion may be biased in this regard. The biggest issue from my perspective on SFP scopes is that they are truly limited when it comes to Elevation and windage hold overs, mainly for wind and movers when things get close. Since you have to be at max magnification, anything that is closer then 400m and mobile can be a pain to trap with a 10-12x powered scope, which seem to be the most common SPF max magnifications I see throughout the industry. Anything higher then that IMHO is not terribly useful for the mil/LE precision marksmen as the magnification at the top end becomes a hindrance at close ranges, magnifying every movement and limiting the FOV available. It makes it even more of a PITA when trying to take an accurate mil reading. The best accessory for someone who is limited to a SFP scope is a good LRF.
FFP
Pro's- The FFP scope offers a lot of flexibility for the professional marksmen. You have the choice of dialling or holding over at any magnification distance. This also gives you a much more flexible scope for using forward mounted NV devices like the PVS-27/30. Lets also get something straight. Just because you have 15-27x of magnification doesn't mean you have to use it to make a shot. It just makes the scope more flexible for both shooting and observation This gives a shooter/spotter team the ability to double their firepower and lethality, allowing for a spotting scope to stay in the rear and another weapon system to be fielded, with each person spotting for the other. Rarely have I ever seen the need to go above 20x on a spotting scope to see trace/impact, even at extended distances so I'm not terribly convinced of their usefulness these days. Mirage can make that even worse at extended distance. Again, a FFP gives the shooter a lot of flexibility. It's even better if the shooter and spotter are shooting similar or the same reticles, so the cross talk/chatter is cut to a minimum. Also something to note with FFP scopes- its a huge benefit if your calling your own shots and making corrections to have your scopes adjustments and reticle be in the same value ie Mil/Mil and MOA/MOA. I personally prefer mil's as the math is more streamlined for what I'm used too. This makes for very fast adjustments and shot to shot corrections, and less mental effort to produce a hit.
Cons- First of all, because the design is more complex, the price typically follows that trend. Light transmission can suffer a tad due to the additional glass. Because there are a quite a few different zoom ranges available across the market you also can run in to issues the reticle becoming less then helpful at lower magnification ranges. Some scopes, like the venerable 5-25x Schmidt and Bender PMII have "tunnelling" issues at low magnification. Mine begins at 8x and this is corroborated by other S&B owners. My NF BEAST also tunnels buts closer to 6.5x so not a huge issue. Tunnelling is identified as you dial down your scope and notice that at a certain point, the FOV stops getting wider and you get the visual effect of looking through a toilet paper tube. With FMNV there also is a few issues with regards to magnification. FLIR and FMNV are limited on their resolution. Because their resolution doesn't change relative to the scopes magnification it can render the high magnification range of a FFP scope pretty much useless. This isn't a con so much as something to be aware of if you have access too and regularly use such devices.
In the end, pick what is best for your uses BUT, making the effort to understanding everything about your equipment and how to take advantage of it.
Last edited:
Richard Boucher
Newbie
Matt, I am sure that is a typo and you meant second focal plane and not single. The difference is the location of the reticle as to whether the reticle enlarges with the variable power or sets fixed. I do not like second focal plane scopes and it is due to my requirements of using for the last 40 plus years of mils and mil based reticles. Under stress, trying to compenstae for my mils being useless due to not being at the right place is a pain. Even a 10 power scope on full power may not be the correct setting for the scope, you must test it on the range to find the correct setting. Advantage of second plane, the reticle can be much thinner as it will never get bigger OR smaller while powering around. For competiton shooters, or shooters at very close range only, this is fine. For guys that are going to have to power down for CQB and then power up for the occasional long shot, no problem. but someone that depends entirely on his shots being made by accurate reading and utilization of hte reticle, then frist focal is what you need and not second. That shooter will seldom use his scope at the lowest power, and when he does, the reticle will be barely visible but there, while at the higher power it will be there. The advantage is that the reticle will stay a set thickness in moa but not in vision. Again, it is mostly a problem close up and at low power.
The M110 was an unmitigated abortion that was fought against at all levels BUT at the very highest. There were better systems and scopes out there, but Reed won. I do not like him nor his weapons, but he has the power, or had the power to do just about anything he wanted to do, just as Ronnie Barrett has done.
The M110 was an unmitigated abortion that was fought against at all levels BUT at the very highest. There were better systems and scopes out there, but Reed won. I do not like him nor his weapons, but he has the power, or had the power to do just about anything he wanted to do, just as Ronnie Barrett has done.
Ahh, yeah my mistake. Thanks for the catch. And no that wasn't a typo, somewhere I picked up "Single" instead of "Second" and it seems to pop up when I'm jamming away typing. Funny how the brain works, No idea why I do it.
I'm in the same boat regarding SFP as to why I like FFP. Another thing I forgot to add- While the FFP scope makes the lower magnifications less usable for shooting off the reticle, but for general observation and taking close shots that require limited precision and can be accomplished with rough holds.
Also in the same boat regarding the M82/107's. We could have had such an incredible capability increase with a .338... but instead we got a 3 MOA boat anchor. By comparison the M110 was a scalpel despite caliber limitations.
I'm in the same boat regarding SFP as to why I like FFP. Another thing I forgot to add- While the FFP scope makes the lower magnifications less usable for shooting off the reticle, but for general observation and taking close shots that require limited precision and can be accomplished with rough holds.
Also in the same boat regarding the M82/107's. We could have had such an incredible capability increase with a .338... but instead we got a 3 MOA boat anchor. By comparison the M110 was a scalpel despite caliber limitations.
Richard Boucher
Newbie
I first started fighting for the 338 in the 338x416 carnation in 86. Fought again all through the 90s and into 2010. too many decided on the 300 instead because teh ammo was present. I also fought for the multi caliber in the 90s. Why train a guy on different platforms shooting different ammo when you can use the same platform AND the user can change barrels when they are shot out. Oh well, discussed this with the bean counters and they won. I retired.
Yeah, I was mildly pissed that the PRS and swappable calibers wasn't made available for both GPF and we got stuck with the sub-par optic's (although S&B has been a barrel of freaking monkey's lately). 300 WM is great, and has a lot of potential but the barrels don't last long on the Magnum's. So what is a guy supposed to do if his gun goes kaput mid tour? 2k rounds goes pretty fast in that environment, and thats about average for 300WM. I've heard claim the melonited barrels Remington is using are getting 3k but I have my doubts. Mk248 (A191) apparently is loaded pretty damned hot as well and does not play well with civilian 300WM chamber's.
Richard Boucher
Newbie
If you shoot the 300 gr suckers you can expect burn out between 500 and 1000 rounds. SURPRISE!! I have never really been a fan of 300 Win Mag. It head spaces on a rim that is not always the same. This changes in bullet jump can effect accuracy and will explain some uncalled wide flyers that occur with 300. There are better rounds out there and some are better than the 338. However, the bean counters stay wiht what is on the books to save money. This is historical and the reason for delays in obvious needs. It is from teh disaster of having so many different calibers in stock just before the civil war and why it took so long to go to a repeating rifle.
The 215 and 230 Bergers are were its at in that arena, but the 220 SMK in the Mk248 Mod 1 is a pretty decent, which is a shame since the GPF guys won't likely see that for quite some time tell the A191 is all eaten up. I have yet to see a 300 grain bullet in a 300WM however.
From what I gather, all my buddies who have messed with the 2010 are pretty happy with it. Its not a perfect solution, but the enhanced capability and ballistics makes its increased length and weight worth the squeeze. Now if they can just unfuck the CSASS....
From what I gather, all my buddies who have messed with the 2010 are pretty happy with it. Its not a perfect solution, but the enhanced capability and ballistics makes its increased length and weight worth the squeeze. Now if they can just unfuck the CSASS....
Richard Boucher
Newbie
We use the 300 as well as the 250. It will hit the regular ammo points shortly. I shot in the shot out for the 2010. There was a bunch of back and forth on the weapon. Also worked on the PSR for way too many years. That too has been an argument over caliber. What the guys have now is heads and shoulders above what I had in 68 - 85 (1903A4 with M84 scope, Remington 700 with Redfield Accutrac, Winchester 70 with Unertl target scope, and M21 with ART I and ART II). I worked on the M24 project when it was only an SF program, and then went to Benning for the down select. Iahve watched things get better and better for the snipers and have high hopes for the future. At 67 I am just too old with little patience for stupidity from bean counters so left the arena. I am now on the outside, sort of, they keep draggin me in sometimes, looking in. 
tylerw02
Regular Member
300 gr bullets in a .300 Win? Sure you aren't thinking of .338s?
Also, a SFP can be used for holds at lower than set power. It's less than ideal, but a descent work around. For scopes with .5 mil subtensions, back to half power, then they are 1.0 mil. Some scopes, like Vortex PST SFP have a deferent at various powers.
I'll personally take FFP with anything over 10x. Under 10x it's not so critical.
Sent from my iPhone using Tapatalk
Also, a SFP can be used for holds at lower than set power. It's less than ideal, but a descent work around. For scopes with .5 mil subtensions, back to half power, then they are 1.0 mil. Some scopes, like Vortex PST SFP have a deferent at various powers.
I'll personally take FFP with anything over 10x. Under 10x it's not so critical.
Sent from my iPhone using Tapatalk
Yup, SFP can be powerful tool, but halving that magnification brings its own challenges, esp with a 10x... now your trying to shoot further with far less magnification and your fine values become a lot less distinguishable. That and not every magnification dial is perfect as with any mechanical system... it could be more or less half mag to get the desired effect and is something that takes a little trial/error.
Richard Boucher
Newbie
Tyler, you are correct, I was holding three conversations at the same time and cross threaded them. A191 is 190gr and the newer ammo is 250 gr, that is the one that can eat a barrel in 500 to 1000 rounds. Sorry, will try to keep my old brain working properly, at 67 crossed threads can be a problem.
The work around for SFP scopes works on the range, not so much in tactical situations under stress and in subdues light. I know, BTDT. It sucks. Teaching studetns to do it is even more of a disaster when they are being evaluated. If you are not using mil or moa reticles, it makes no difference. In the 70s and early 80s SFP was preferred due to the fact the reticle could be finer. With a known set distance in the reticle, either the range lines in the accutrac, or just the distance from heavy bar to heavy bar on the duplex scopes, you could estimate range nicely by using the end power setting. Again a problem under low light conditions, seeing the power setting. In my opinion, if you have a mil based reticle, or a moa based reticle, you need a FFP or you will screw up. There are two types of shooters with SFP and mil reticles, those that have screwed up and those that will. This is not just my "opinion", it is what I have observed over years of working with all types of scopes and weapon systems. Yes, I am one that have. The Europeans have tried to go to the SFP for the finer reticle, and have even placed a tab on the power ring to note half power. Unfortunately, as I have stated earlier, a full mil may not be at the power ring stop, it could be a bit before it. The NF scopes that came with teh Mk13s almost all measured a correct mil at another location other than full power stop. Shooting at night with NVDs and having to power down to obtain a clear sight picture was a screw up waiting to happen and usually did. Add a no zero stop and the scopes were a pain to work with.
If you chose a SFP scope and a mil reticle, and that is your choice, be sure to practice with it. You will have a problem in many situations. FFP and I do not have to worry about my mils being correct where ever I power to and in low light I do not have to worry about not being on the correct power for my reticle. Using anything below 10 power as a standard for FFP or SFP can bite you. Just be aware of those facts. If you are shooting with innocents or buddies within you target area, then you do not need another location for Murphy to sit.
The work around for SFP scopes works on the range, not so much in tactical situations under stress and in subdues light. I know, BTDT. It sucks. Teaching studetns to do it is even more of a disaster when they are being evaluated. If you are not using mil or moa reticles, it makes no difference. In the 70s and early 80s SFP was preferred due to the fact the reticle could be finer. With a known set distance in the reticle, either the range lines in the accutrac, or just the distance from heavy bar to heavy bar on the duplex scopes, you could estimate range nicely by using the end power setting. Again a problem under low light conditions, seeing the power setting. In my opinion, if you have a mil based reticle, or a moa based reticle, you need a FFP or you will screw up. There are two types of shooters with SFP and mil reticles, those that have screwed up and those that will. This is not just my "opinion", it is what I have observed over years of working with all types of scopes and weapon systems. Yes, I am one that have. The Europeans have tried to go to the SFP for the finer reticle, and have even placed a tab on the power ring to note half power. Unfortunately, as I have stated earlier, a full mil may not be at the power ring stop, it could be a bit before it. The NF scopes that came with teh Mk13s almost all measured a correct mil at another location other than full power stop. Shooting at night with NVDs and having to power down to obtain a clear sight picture was a screw up waiting to happen and usually did. Add a no zero stop and the scopes were a pain to work with.
If you chose a SFP scope and a mil reticle, and that is your choice, be sure to practice with it. You will have a problem in many situations. FFP and I do not have to worry about my mils being correct where ever I power to and in low light I do not have to worry about not being on the correct power for my reticle. Using anything below 10 power as a standard for FFP or SFP can bite you. Just be aware of those facts. If you are shooting with innocents or buddies within you target area, then you do not need another location for Murphy to sit.
So on a second focal place scope - a 2.5-10x, if I have magnification at 5x, would my reticle be at half values?
Really? Are you talking about the 220 SMK version or the 190 grain?
Yeah NF is known for good accuracy in that area, I was just making note of it so people are aware that its not all the same for every maker of SFP scopes.
Ditto on the Mk4 Mil/MOA non ZS, none locking abortion for low light work. I was always quite jealous of the glass the USMC had for their Snipers.
Yeah NF is known for good accuracy in that area, I was just making note of it so people are aware that its not all the same for every maker of SFP scopes.
Ditto on the Mk4 Mil/MOA non ZS, none locking abortion for low light work. I was always quite jealous of the glass the USMC had for their Snipers.
Theoretically, double the value. Assuming the reticle is calibrated for 10X. In actuality, it may or may not be exactly double, hence the need to be at the designated power.