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Rock river lar-8 20th bull barrel

216 Views 8 Replies 3 Participants Last post by  FL Moore
Just picked this up need to move the scope get new mounts. And a bipod I'll see how it does later.


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That scope is mounted too far rearward for you to get good head placement and eye relief while maintaining good contact between your shoulder and buttplate. You will be trying to “turtle” your neck back to center your eye in the correct position.
Here are a couple of pictures of scopes mounted for optimum head position from multiple firing positions. Notice how far out over the hand guard the scopes are positioned. I would turn the front ring 180 degrees and move the whole setup further forward. Leave the rings loose and get behind the rifle, then get a good head position and slide/move the scope and rings to get the best sight picture possible. Then you can torque down the fasteners. Just my $.02 View attachment 846659 View attachment 846660
I'm fixing that when I get home that was the first thing I noticed. Thanks btw
Just wanted to point this out I'm not to falimar with ar-10's but that is a chunky BCG.
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Yes, larger case head diameter (.473” vs .378”) and higher SAAMI max chamber pressure (62,000 psi vs 55,000 psi) means more steel to keep it in check. Coupled with a longer stroke, that bolt carrier group will feel much different than an AR-15 while cycling, especially when it slams back into battery.
Compared to the other ar-10s I have seen this has more weight and heft
You’re going to like that but you’re going to have to set it up right !!
Just picked up 2 more 20 round mags for the rock river today. I'm pretty much set on the scope mounting it's not ideal but any more foreward I don't like it even with the eye relief backed all the way out. Put a few shots through it today it fed and cycled 4 different kinds of 308 ammo beautifully. From all 4 mags I love the gun the trigger is solid. Bi pod is on the way.
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