Rifle Scopes  PRS Gas Gun magnification: 3-15 vs. 5-25 for a 223 AR?

couch-sniper

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Oct 31, 2017
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Hello, I'm looking at the Vortex Viper PST Gen 2, and can't decide between the 3-15 and 5-25. I will mostly use it on my .223 AR on steel plates out to 500-600 meters (550-650 yards). Later it may also be used on a 6.5 bolt gun. I'm thinking the 3-15 is more at home on the AR, but I wonder if I'm missing out on something with the 5-25 which has more magnification. Will the higher 5.25 magnification be useful in stages with unknown distances where you have to mil the target? Will it be better in low light? Does the 5-25 have a clearer image on 15x?
 

FUNCTIONAL

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  • Feb 19, 2012
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    I cant speak to the PSTii specifically but I have scopes with those mag ranges for prs rifles.

    for matches I rarely ever go above 15x and spend most my time at about 10x.... even with my 4-27x scope. For ranging the extra power helps when the heat/mirage cooperate, i was able to mil at max power for only about 1hr of the day...after that I had to back it down to 18ish power to get any decent reading on the plates.

    You do gain a sizeable advantage on your low power field of view. If you plan on using it for things other than prs matches (some faster/dmr type matches) id go 3-15 otherwise the 5-25 will give you more flexibility.

    also i dont know this answer but the eye box on the 5-25 may be less forgiving than the 3-15...something to take into consideration.
     

    VegasHKShooter

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    Feb 28, 2013
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    For the useful distance the .223 round, the 3-15 will be plenty of scope. You can get to 1K on 15x, so you'll have that. Likely, the eyebox will be better on the lower power, the field of view will be better. Up to you, but I feel like 5-25 is way overkill for an AR-15.
     

    Peter Laurvick

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    Jul 4, 2017
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    Can’t speak to PRS matches but I’ve run a Nightforce NXS 3.5-15x56 SFP on several ARs and it fit quite nicely. Maybe a little to big even. Now I run. Nightforce ATACR 4-16x42mm Tremor 3 on a 6.5 Grendel. It it far superior for how I use it but unless I’m shooting past 500yds I rarely run it higher than 12x, the crisp and clear quality of the glass definitely play into that I’m sure. I’ve been able to easily shoot groups and spot my hits on 16x out to 800yds so far. Would have no worries about being able to see/shoot out to 1,000yds
     

    lennyo3034

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    Apr 18, 2010
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    Do you foresee your matches having a lot of movers? Especially faster speed movers? I like a scope with a useable reticle at low mag for that purpose so I would lean towards the 3-15.
     

    mpk1996

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    Apr 25, 2013
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    for the PRS gas gun series type shooting, you will want something in the 3-15, 3-18, 4-16 range for sure. or even a 2-10 range. so, that's where I would start. I think the 5-25 will be to big and if the targets are close, you will want the lesser mag. but the real reason is that those scopes are much heavier and will feel awkward on a small frame AR, even with a 20" barrel. I did run a kahles k624 on my 6 creed large frame AR. it was fine, a little big, but the larger size of the AR10 and 22" heavier barrel helped balance it out. I run and have run a NF 4-16 and leupold mk6 3-18 on my 20" .223 guns and they are both great.
     

    IanHusaberg

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  • Feb 19, 2017
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    I have a 4-16 on my gas 308. On my PRS bolt gun its 4.5-27. Last competition I used 15-18x the most. When you only have two minutes to shoot a stage that has 5 different targets traversing entire hillside from 700-1130 and barley enough time to adjust dope on your scope and make two shot per target and find that said target. Field of view goes along way in PRS matches. I set my parallax somewhere in the middle and roll with it as well. Mirage has less of an affect when at lower magnification. I have found that the more money you spend on a scope, the more coatings you get with a scope that mitigate mirage at distance. It doesn't change mirage coming off your barrel after a long shot string on a hot day, with a hot load.

    I do like using higher magnification for load development and zero confirmation.
     

    patriot07

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    Oct 17, 2017
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    For 223, and especially on an AR, I would think the 3-15 would be a better choice.

    And on the PST2, as much as I thought the glass on the 5-25 PST2 is a small step above everything else in that price range, I think the 3-15 PST2 glass was a even hair better. It's really an awesome scope.
     

    Danattherock

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  • Feb 17, 2017
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    I have shot four PRS matches this year, only one gas gun though, and heading to my 5th PRS match Friday in WV. Shot about 15 club level matches, several with gas gun. Perfect gas gun optic to me is Bushnell DMR II 3.5-21. Bought one for a 6.5 Grendel I had built for 2018 PRS gas gun and 3 Gun Long Range matches. Solid scope with proven record of tracking.
     

    ddavis

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    May 26, 2011
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    I ran a Primary Arms 4.5-14 with the ACSS reticle for the one major gas gun match I shot. I got the BDC to line up with my load out to 800 and it was very fast to use the reticle vs. dialing. I think I stayed around 12-14x most of the time. I normally don't go above 18x even for the bolt gun matches. Given the choice between a 3-15 and a 5-25, I'd go with the higher mag. Chances are, you'll never go below 8x or so at a match that is steel targets, which most of them are. You won't be shooting closer than 100 yards for the most part, and the reticle in a FFP isn't really usable at low mag anyways. Even if you don't use the upper end of the mag range much when shooting, it's nice to have for ID'ing targets at 600-800 yards.

    -Dan
     

    BCP

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  • Dec 4, 2008
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    I guess that would depend on the 3-15 and 5-25.

    If the 3-15 is much lighter, more compact and "most" people seem to think it has "better glass" then it's probably the better choice.

    One thing I will say is that after using a 4-14x50 on my bolt action tikka project budge blah blah "precision" rifle for awhile I kinda want more magnification, especially for shooting paper.

     

    couch-sniper

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    Oct 31, 2017
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    Thanks for the replies. This wasn't going to be easy.. :p

    While the 3-15 may be "more at home" on the AR-15, I would like to learn to read wind by mirage and guess the 5-25 would be more suited for that? Or would the 15x be sufficient for that in most weather conditions? I'll also run a 45 degree red dot.

    The weight difference between the PST G2's is 3.1 ounces / 88 grams.
    - PST 3-15x44 weighs 28.1 oz / 796 g
    - PST 5-25x50 weighs 31.2 oz / 885 g

    Allthough not a requirement, it would also be nice to do indoor precision training with .22 LR at 15 meters (16.4 yd), and parallax error comes to mind. Would it make a big difference that the 3-15 has parallax adjustment starting at 18 m, while the 5-25 starts at 22.8 m?

    As far as field of view.. Will they have the same field of view when both are at 5x? And 15x?

    Field of View, PST 5-25:
    5x, 24.1 ft at 100 yd / 8 m at 100 m
    25x, 4.8 ft at 100 yd / 1.6 m at 100 m

    Field of View, PST 3-15:
    3x, 41.2 ft at 100 yd / 13.7 m at 100 m
    15x, 8.6 ft at 100 yd / 2.8 m at 100 m