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Posted: 12/21/2016 12:13:56 AM EDT
| I bought a vortex Diamondback 4-12x40. My question is how do I know my scope won't be blocked by the stock front sight post. Amazon has vortex "high" scope ring mounts for $20. Do I have to buy the more expensive ones to raise it high enough to miss the front sight post? Is there a way to know ahead of time? |
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A 4-12x scope cannot focus close enough to "see" the front sight post. You literally look right through it like it is not there.
But you do need a cantilever mount to get the scope to the correct height to match your stock and push it forward enough to give you proper eye relief. If you try to use separate rings, the front ring will be suspended in the air. |
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Here you go OP this is probably the cheapest one piece mount I would look at, don't get rings they will not work for an AR well. The scope needs to be higher and cantilevered forward to use the scope properly.
https://smile.amazon.com/dp/B004P81FMU?tag=amz-mkt-chr-us-20&ascsubtag=1ba00-01000-s1060-win70-other-smile-us000-pcomp-feature-scomp-wm-4 |
| Like they said, the front sight base 'ghosts out' with a magnified optic, so be clear on that - you don't need to raise the scope on that account. You do need to set the scope to a height that allows a good cheek weld. You have to locate the scope fore and aft for the recommended eye relief. You can get a clue from a standard AR15 with iron sights; if that feels 'right' to you, allowing a good cheek weld, then that is the centerline height of your scope. All you have to do then is use the measurements of the bases you're interested in to determine which height is for you. Mounting the one-piece base on your rifle's receiver rail eliminates some alignment problems that you can have with separate rings but you have to know that your scope will fit the base you want not only in diameter but in locating the end lens at the proper position for you. IOW, imagine the scope could 'slide' a bit in the mount but movement is limited by the rings and features of the scope. You have to be sure the mount and scope you want will actually work to produce the eye relief you need with the mount attached only to the receiver rail unless you have a 'monolithic' receiver/rail. |
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You're going about this a little poorly, don't take that the wrong way. Let me see if I can help.
You don't want rings, you want an offset one piece mount. Your rings would need to both be on the upper receiver, which would make the scope sit way too far back for any kind of non-fucked up shooting position. The only other alternative is to mount one ring on the upper and one on the rail which is at best risky and at worst will break your shit pretty quickly. An offset mount allows you to hold the rifle correctly, while holding the scope far enough out for proper eye relief. The height doesn't matter in relation to seeing past the front sight. Get the height that works for you and your cheekweld, usually around 1.5" from top of rail to optical centerline. At about 3-4X you can sometimes see a small blur in the lower third of the optic, but nothing worth worrying about. Below 3X and it becomes less blurry, but still not something you notice in real world use unless you're looking for. At much above 4X it zoomed straight through it and I've never really noticed it at all. TL,DR: You want an offset mount. For non-QD I like the Aero Precision Ultralight. If you shoot with your nose to the charging handle, you probably want the SPR model, if not you'd likely want the extended. I wouldn't go too much cheaper than that, unless you like re-zeroing your optic every time you bump it or look at it funny. |
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Quoted:
Why not 1. cut it off with a dremal just above the gas tube. 2. get a yhm fold down style front sight / has block such as their 9394 Because folding gas block sights suck? Because YHM sights and that gas block in particular suck? Because you are better off getting a longer rail and putting a low profile gas glock under the rail with a flip sight on top to save weight and gain rail space. Those are just off the top of my head... I'm sure there are more reasons to not do that. |
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Vortex, Aero Precision and Leupold all make cantilevered scope mounts for around $80.00, you'll need one to get the eye relief necessary for using a high magnification scope. Buying it is a requirement, not an option. Standard scope rings, even the extra high models (1.4" to 1.5" centerline) won't work because the standard AR-15 upper receiver rail is too short to accommodate a high magnification scope with the spacing needed to mount it properly.
Some rifles (Larue for 1) have full length uninterrupted rails that will allow for the use of rings alone. Most people suggest against mounting a scope with one ring on the free float tube and one on the upper. The rifle flexes when fired and the handguard and rail are rarely perfectly aligned. This can cause undue stress on the scope tube and may even damage the scope if torqued enough. As people already mentioned, magnification makes the front sight invisible because it's so out of focus. At the most you will only see a faint shadow of the front post and only when the scope is turned all the way to the lowest magnification. Anything higher than 3X or 4X and it will totally disappear. |
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Quoted:
Vortex, Aero Precision and Leupold all make cantilevered scope mounts for around $80.00, you'll need one to get the eye relief necessary for using a high magnification scope. Buying it is a requirement, not an option. Standard scope rings, even the extra high models (1.4" to 1.5" centerline) won't work because the standard AR-15 upper receiver rail is too short to accommodate a high magnification scope with the spacing needed to mount it properly. Some rifles (Larue for 1) have full length uninterrupted rails that will allow for the use of rings alone. Most people suggest against mounting a scope with one ring on the free float tube and one on the upper. The rifle flexes when fired and the handguard and rail are rarely perfectly aligned. This can cause undue stress on the scope tube and may even damage the scope if torqued enough. As people already mentioned, magnification makes the front sight invisible because it's so out of focus. At the most you will only see a faint shadow of the front post and only when the scope is turned all the way to the lowest magnification. Anything higher than 3X or 4X and it will totally disappear. Well-said. I did suggest as a budget alternative the two piece Nikon P-Mount Rings. Each ring is sepatately cantilevered forward so that the ring is forward of the base. It results in the same height and forward placement of the ring as the one piece cantilever mounts. That design enables keeping the front mount on the upper receiver, while allowing the scope to be positioned forward enough to ususlly get decent eye relief. The only real benefit is at $50 for the pair, they are about the cheapest thing that works. Kinda wierd looking, to me, but users seem to be satisfied with them. It would be better for OP to spend the extra for the $80 Leupold Mark 2 IMS or Aero Precision one piece mounts. I have used tge Leupold IMS and it is solid. |
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