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What troubles have you all found with a system, like the PS90, where the site is so much higher than the barrel, . . . specifically when you are changing the distances you are shooting?

For example, what is the aim point at 25, 50, 100 yards, and are you having to adjust where you're pointing the site to get it to hit where you want it to go.
 

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:) There is a lot of info on this forum. Here is what you might be looking for in the FAQ sticky in this General PS90 Discusion section.
Check out the wikapedia link. There is a great ballistic graph there.
Have fun learning. There is A LOT to know. :D





Q: Is there an issue with having an aftermarket optic sit so high up over the bore of the rifle?

A: This can be a hotbed issue - especially among people who do not even own a PS90 themselves. Logic would dictate that the higher off the bore your optic is, the more variation you will have at distances outside of your zero. But, when one accounts for the fact that the PS90 is made to be a personal defense weapon, NOT a long range sniper rifle, this bore height issue really is a non-starter. You probably will not be shooting this gun out at super long ranges. And, within the stated range of the PS90 (200 meters - which is really stretching it anyway without a magnified optic), the optic height above the bore doesn't really matter much.

In fact, when the PS90 first came out, many people (including members here) even went to modifying and cutting up their receiver, so they could make their aiming optic sit as low as possible.

The stock optic on the PS90 is sighted in at 50 yards. At 25 yards, it will be approximately 2 inches low (you can see a ballstic chart of the 5.7 round, and more info on the PS90 here: http://en.wikipedia.org/wiki/PS90 ). Truthfully after replacing my white ringed sight with an Eotech (which does sit a bit higher), I get the same variation. And, ANY rifle has variation when you shoot at different ranges closer and further than your zeroed distance.
 

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....dont even get me started about having a laser TO THE SIDE of the barrel.

I get confused every time I use the darn thing.....gee, the circle-dot on my holographic doesn't match the laser....oh wait....lets see....I am closer so the laser should be to the right...but wait if I am ......uh.....
 

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When zeroed between 50 and 100 yards you can expect to hit a few inches low at close range.

A zero of 25 yards is absolutely useless at longer ranges because the line of sight is at such a downward angle that shot taken at 100 yards will be feet above the target.

An after market rail mounted Eotech has the least vertical deviation when zeroed at 90 yards. From about 60 to 200 yards the POI stays within an inch of the POA.

For people who never shoot beyond 100 yards I would recommend a zero @ 60 yards. With an Eotech zeroed at this range you can use the bottom circle mark to aim in very close quarters.

To answer your question directly here is some data I gathered by shooting targets at various ranges and zeros using my PS90 USG w Eotech.

SS195



Zero @ 55 yards


-2.5" @25y _____ -.5" @50y ____ +3" @100y____ +5" @150y____ +5"@200y

zero @ 75 yards

-3" @25y ____ -1.5"@50y ____ +1"@100y ____ +2"@150y ____ [email protected]

zero @ 90 yards

-3.25" @25y____ -2"@50y [email protected] ____ +1"@ 150y ____-.25"@ 200y
 

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Thanks!
Funny I was looking for this. I have been plinking for long enough. Time to get this thing sighted properly. Happen to have the same for a Five seveN.
 

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I found a zero at 40 yards works well for me. It puts me 2.5" high at 100 yards, right back on at 180, and only 1.5" low at 200. Works very well for punching paper, but smaller targets may pose a challenge.
 

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My range is just 25/50/100 yards. So, mine is set at 50 yards. 100 yards is too far for me to see with an Eotech. I can hit a sihloette target at 100, but not in a "group" size.
 

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I strongly disagree with the FAQ here. How many people would ever use a PS90 at 50 yeards, 100 yards, 200 yards? If anybody ever used a PS90 in a defensive situation, it would probably be in a case of home protection where distances encountered are usually less than 15 yards. Having your POI deviate from your POA by 4" or so is a significant disadvantage.

It's actually with long range shooting where it's not critical to have your optical axis close to your bore axis. Lots of cool-aid and spin here. Before anybody labels me a PS90 hater, I got 2 of them. I like them for what they are though, and am not going to make up silly excuses for what they aren't.
 

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My range is just 25/50/100 yards. So, mine is set at 50 yards. 100 yards is too far for me to see with an Eotech. I can hit a sihloette target at 100, but not in a "group" size.
I've shot my PS90's as far as 300m but like ShipWreck I believe the PS90 is a CQB weapon so w/SS197 & the ultralow TROS Aimpoint mount I sighted in at 50yds as well which still puts me just about dead-on at 100yds.
Tomac
 

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QUOTE
If anybody ever used a PS90 in a defensive situation, it would probably be in a case of home protection where distances encountered are usually less than 15 yards. Having your POI deviate from your POA by 4" or so is a significant disadvantage.

At 15 yards the POI will be more about 2" low from POA. At that distance I use my laser or just "look shoot". The PS90 is a CQ weapon so I only use it at a MAX range of 100 yards. 25 to 50 yards is more standard shooting with this weapon for me. fits the bill for home protection! :shock: :?
 

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Are these weapons built for distance or is it just a perk of a 16''bbl? I zeroed mine at 30ft.. Allows for fast aquisition at short range.. Close quarters stuff. I have a rifle if i want to shoot farther.

Im using an aluminum C-more on a PS90 TR :twisted:
 

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I have mine set up for close quarters, from my living room wall to my bedroom window, about 35 ft. My eotech and green laser zero up nicely. Its cool because the center red dot on the eotech will turn green when it is zeroed with the green laser. With the red outer circle it looks cool. Generally these are for close quarters. You can use them for long range to a point. I know the idea of having a "transformer" for a gun is cool. Long range one second, close quarters the next. I prefer to stick with the weapons primary function which gives me an excuse to buy more guns for all scenarios!
 

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Having the optic closer to the barrel is good for CQB and for longer range stuff.

That is why I chopped - and it works. The only disadvantage I have now is if I wear a gas mask. There is no way I can acquire the red dot. Since I am not planning on defending myself at nuclear power-plants or engage anyone tossing capsicum into my living room - it's a non-issue.

The practical application of having the sight sit so high with the PS90 is the fact that you can raise the weapon, acquire target and put a lot of rounds into center of mass without having to cheek weld the weapon.

This works fine for up to 10 yards, room or automobile scenario. What happens if you have a hostage at 15 yards and are offered a head shot only? Do you have the time to calculate where your point of impact should be? If you can shave the deviation from 1.5 to .5 inches, would you not take it?

-TH
 

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The majority of the time I shoot bowling pins set up at 15 yards to 50 yards. with the standard white sight w/REM T3. They seem to go down pretty well as long as I do my part. I don't see it as a big issue as long as you aren't trying to make a PS90 into a sniper rifle. At 100yards I can get 3-5 inch groups most days, smaller when I haven't drank that much coffee (that happens rarely).
 

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Thermallator said:
What happens if you have a hostage at 15 yards and are offered a head shot only? Do you have the time to calculate where your point of impact should be? If you can shave the deviation from 1.5 to .5 inches, would you not take it?

-TH
With an eotech, I know where the point of impact is really up close, even though the gun is sighted for 50 yards. I know that at very short distances, it hits on the bottom tip of that outer reticle. That's why I like the EOtech over a standard red dot.
 

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i have mine ps90 with eo tech set up for 50 yards as well, this zero lets me engage target from contact - 100 yards just put the red dot on what i want and i know it will hit very close, it you expect more than that in a fire fight you're over thinking the situation.
 

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I have a PS90 TR Eotech551,TLR2 on side rail. 2in low at 50 yds, dead on at 100 yds. The laser is sighted in at 15 yds, and like Ship said the bottom ring on the reticle on the Eotech is on target also at 15 yds.
 

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Well, as mine is sighted at 50 yards, the bottom edge of my eotech circle tells me where it will hit at 7 yards (and a little closer). So it works well.
 
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