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7/1/2017 3:03:06 PM EDT
Mark 4 3.5-10 mounted on a YHM riser bridging the gap between upper and rail. The riser is solid as a rock and I can't imagine it moving. Opinions??

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7/1/2017 7:55:34 PM EDT
[#1]
The only issue I see is the added weight plus your height over bore to the center of the optic is a little higher.   This set up gives you a little more room for a rear BUIS, if it works for you, use it.
7/1/2017 8:13:50 PM EDT
[#2]
How much of a gap did you have? That mount looks like it could have handled it.
7/1/2017 8:44:57 PM EDT
[#3]
Quote History
Quoted:
The only issue I see is the added weight plus your height over bore to the center of the optic is a little higher.   This set up gives you a little more room for a rear BUIS, if it works for you, use it.
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Don't mind the weight as I'm not really lugging it anywhere and also have a lightweight ar if the zombies show up and I need to move fast. I have a tall head so the HOB is actually works well. It's a 1.25" mount + the .5" riser for 1.75" total. Just didn't know if bridging a riser across upper and handguard would be a bad thing.
7/1/2017 8:46:42 PM EDT
[#4]
Quote History
Quoted:
How much of a gap did you have? That mount looks like it could have handled it.
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I really needed a bit more than the mount could give and may even move it forward some more. I could get a new mount but actually like the height and the look. Do you think there is an issue with the bridge though? I can't imagine it moving but I've been wrong before!
7/2/2017 4:51:58 AM EDT
[#5]
Maybe move the rear sight back one rail slot, the riser and scope back two slots and move the scope forward in its rings?  That should produce the same eye relief and get the riser back entirely on your upper.  Of course, the downside is that you will need to rezero.

While your setup looks solid enough, your bipod is working like a lever against a fulcrum on the rail attachment point.  That will potentially put pressure on the front of your scope mount.

You may see vertical stringing of your groups like not having a free float rail.  In this instance the barrel remains stationary, but the scope might get levered upward by pressure on the rail enough to produce stringing.  It only takes a few thousandths of an inch deflection to move your group several inches at 100 yards and over.
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