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Discussion Starter · #1 ·
well, no more than any other. Just thinking physics and the way that problems manifest themselves on forums. But there is really nothing more brutal with a SCAR than any other .308, and that those of us who broke a scope, just happened to do so when mounted on the 17. Since mine is in for repair I mounted a sub $100 BSA and it's yet to do anything but work just fine. So far held up better than the Zeiss, which I think proves I just got a bad one. Obviously a strong well made scope is more durable, and my cheapie scope might have a short life, but it would on a bolt gun as well. I'm going to keep banging out rounds with this scope until my repair gets back. The BSA has even withstood the low teen temps we're stuck in. So far the rifle hasn't even noticed the cold, even as my breath freezes on the receiver.
 

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I personally wouldn't put a scope made specifically for an AR15 (or specifically made for .223 caliber) on the SCAR17, but otherwise most scopes are built pretty stout because the manufacturer doesn't know if you're going to mount it on a .22LR or a .375 H&H.
 

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Discussion Starter · #3 ·
Unless it's a good scope. Kind of what I was trying to say. If it can handle .308, it can handle a SCAR. If a
 

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Earlier this week, I emailed technical support at Burris about their $999 retail 3x15x50 XTR II being mounted on a SCAR 17 in a Larue 104. Their reply was:

Our scopes are recoil tested to handle the recoil of a .50 BMG and. 338 Lapua. We don't not have any worries about the recoil of a SCAR, especially when it comes to XTR II scopes.

Best Regards
Ryan Johnson
Burris/Steiner Technical Support
[email protected]
 

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You may be right but one point you did not mention is the movement of such a large bolt carrier group both backwards to eject a round then the push forward by the spring while loading the next round. Because the scar is a semi auto there is a large heavy group of components inside the rifle moving back and forth every shot which does not occur on bolt guns. Bolt guns and their scopes only deal with the physics behind a bullet being fired not the reciprocation of the auto loading feature. Yes this does occur in AR style rifles as well but the bolt carrier group and the spring that pushes it forward are much smaller and lighter than the proprietary ones found in the scar. So in the scar you have a 308 round go bang which is no big deal but that bang must push the large bolt carrier group back against the spring then the spring slams it forward all while ejecting the old round and loading the new round. May seem like no big deal but the force at which the BCG is pushed forward is why folks believe it is hard on optics.

If you don't think that the bolt carrier group moving has much force behind it just put your hand in the way of the charging handle to feel how hard it pushes back and forward. Just my opinion but this is what I have heard others say also so please don't shoot the messenger.
 

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Yeah i think most of the rumors are just that, rumors. I mean its a fact the 17 has less recoil than most 308s yet its the only one breaking optics? Sounds odd...
 

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as KTM points out its the forward and backwards recoil "impulse" NOT just felt recoil.
not all optics will fail but some obviously will. The SCAR is not the only rifle known
to have this effect.
 

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I'm not quoting this as gospel but the "recoil impulse" of the SCAR is similar to a spring compression air gun. The rearward impulse is no worse than most rifles but the forward action of the heavy bolt assembly is what's been discuss as the possible culprit to scopes demise. This is similar to a normal rifle scope on an air rifle that gets trashed by the forward recoil impulse of the spring. That's been the speculation at least.
I myself have had issues with scopes / optics on both my SCARS, killed a Zeiss Z Point/Kahles Helia C/Burris XTR Tactical. Finally have a Nightforce on one and a Trijicon TriPower on the other with no issues.
 

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I'm not quoting this as gospel but the "recoil impulse" of the SCAR is similar to a spring compression air gun. The rearward impulse is no worse than most rifles but the forward action of the heavy bolt assembly is what's been discuss as the possible culprit to scopes demise. This is similar to a normal rifle scope on an air rifle that gets trashed by the forward recoil impulse of the spring. That's been the speculation at least.
I myself have had issues with scopes / optics on both my SCARS, killed a Zeiss Z Point/Kahles Helia C/Burris XTR Tactical. Finally have a Nightforce on one and a Trijicon TriPower on the other with no issues.
The SCAR isn't the only semiauto with a heavy bolt that slams back and forth.
 

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How about that nearly solid hunk of steel within the FAL cycling back and forth?

How about that heavy bolt unit on the HK G3 family?
 

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You may be right but one point you did not mention is the movement of such a large bolt carrier group both backwards to eject a round then the push forward by the spring while loading the next round. Because the scar is a semi auto there is a large heavy group of components inside the rifle moving back and forth every shot which does not occur on bolt guns. Bolt guns and their scopes only deal with the physics behind a bullet being fired not the reciprocation of the auto loading feature. Yes this does occur in AR style rifles as well but the bolt carrier group and the spring that pushes it forward are much smaller and lighter than the proprietary ones found in the scar. So in the scar you have a 308 round go bang which is no big deal but that bang must push the large bolt carrier group back against the spring then the spring slams it forward all while ejecting the old round and loading the new round. May seem like no big deal but the force at which the BCG is pushed forward is why folks believe it is hard on optics.

If you don't think that the bolt carrier group moving has much force behind it just put your hand in the way of the charging handle to feel how hard it pushes back and forward. Just my opinion but this is what I have heard others say also so please don't shoot the messenger.
In WWII, the Nazis had scopes mounted on their 8mm Mauser chambered full auto FG42. I don't think that .30 caliber full powered cartridge semiauto rifles are a "new" thing.
 

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I use 1x6 Schmidt &Bender works awesome zero problems so far with about 800 rd count ImageUploadedByOutdoor Forums1416807050.661043.jpg
I personally think the SCAR is no harder on scopes then any other 308 Rifle ,....sounds like haters with ARs out there to me LoL


Sent from my iPhone using Outdoor Forums
 

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Eotechs and Aimpoints and various other optics have failed on other rifles, even AR15s. The problem is that most of these people poking at the issue hear it from a friend of a friend who saw on theinternet that SOCOM asked for hardened optics for the SCAR.

Not much details are known, so they let their imaginations run wild. Most credible among the competing theories beyond blaming the SCAR is that the old Eotechs with the batteries running the length of the rifle were bouncing on their springs, leading to the new Eotechs with the sideways mounted batteries.
 

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The SCAR isn't the only semiauto with a heavy bolt that slams back and forth.
Very true but the weight of the heavy bolt would be more dramatic due to the lighter overall weight of the scar. What percentage of the scars overall weight is in the moving bolt carrier group? I would assume even if other rifles had heavy BCGs that there overall weights are much more than scars and that weight has the same affect as on typical recoil. Heavy gun less recoil. Light weight gun same caliber has more recoil. Lightweight gun with heavy moving parts would create more stress on optics. All purely speculation and my opinion, I welcome any facts to disprove this theory.

I have a nightforce 2.5-10 on my 17 and have had no issues. I own 0 ARs and intend to keep it that way... I love my scar.
 

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I don't really want to buy into this Scar specific recoil signature hooplah. When a company claims their optic is rated up to .50 BMG it should be able to stand up to anything. I do mean anything.


case and point.
 

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In WWII, the Nazis had scopes mounted on their 8mm Mauser chambered full auto FG42. I don't think that .30 caliber full powered cartridge semiauto rifles are a "new" thing.
Sorry but I don't understand what this has to do with what I said? I was making reference to a commonly sighted reason as to why the scar MIGHT be harder on optics (playing devils advocate).
 

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Take trijicon for instance. I pulled this off of another forum and it's from a rep.

"Thank you for your interest in Trijicon products. To my knowledge, none of our products have suffered from any type of recoil related failures. All Trijicon products carry a lifetime warranty other than illumination which is limited from 5-15 years depending on the model. Please contact us if you need further assistance. "
 

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Sorry but I don't understand what this has to do with what I said? I was making reference to a commonly sighted reason as to why the scar MIGHT be harder on optics (playing devils advocate).
I think what he meant was that optics designers have this recoil impulse in mind when they design their optics. Meaning that they are aware of the forwad movement created by certain platforms and design accordingly. The WWII Referance was probably to make a point that rifles with a high mass reciprocating BCG have been in use for decades and it's hard to believe that the Scars design created some kind of new optics eating unheard of recoil impulse. But I could be wrong as it wasn't my post...
 
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You may be right but one point you did not mention is the movement of such a large bolt carrier group both backwards to eject a round then the push forward by the spring while loading the next round. Because the scar is a semi auto there is a large heavy group of components inside the rifle moving back and forth every shot which does not occur on bolt guns. Bolt guns and their scopes only deal with the physics behind a bullet being fired not the reciprocation of the auto loading feature. Yes this does occur in AR style rifles as well but the bolt carrier group and the spring that pushes it forward are much smaller and lighter than the proprietary ones found in the scar. So in the scar you have a 308 round go bang which is no big deal but that bang must push the large bolt carrier group back against the spring then the spring slams it forward all while ejecting the old round and loading the new round. May seem like no big deal but the force at which the BCG is pushed forward is why folks believe it is hard on optics.

If you don't think that the bolt carrier group moving has much force behind it just put your hand in the way of the charging handle to feel how hard it pushes back and forward. Just my opinion but this is what I have heard others say also so please don't shoot the messenger.


Ahhh, felt like a baby tap the 1st, and only I might add, time it hit my thumb...!!:cry:
 

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How about that nearly solid hunk of steel within the FAL cycling back and forth?

How about that heavy bolt unit on the HK G3 family?
Funny you mention the FAL. My full auto FAL has never had an issue with a Z-Point, even after doing several mag dumps, but a brand new one on my wifes SCAR shattered in under 100 rounds. Not saying it's for sure the SCAR but it just seems odd to me that I had gone through some of what I consider to be upper end optics. Matters not now, my Nightforce and Trijicon are working great on the two guns so I'm happy.
 
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