Originally Posted By Sc00t3r:
I originally posted this over in GD, but figured I'd share it here as well since it's likely of interest to the optics crowd.

Just wrapped up some time behind the new Primary Arms PLxC RDB 1.5-12x36 during a Sidewinder Concepts Precision Carbine class at The Ranch.

Over three days we shot roughly 1,000 rounds, engaging targets from 100 to 700 yards from prone, barricades, and tripods. After spending that much time behind it, I think Primary Arms may have found a pretty interesting middle ground between a traditional LPVO and MPVO.

Full video review and thoughts here:

Originally Posted By Teller_Ulam:

@Sc00t3r  Could you please tell more about the "Cam Lock" technique mentioned around 2:30?

Originally Posted By Sc00t3r:


Sure, this was one of the biggest "ah-ha" moments for me during the class.

The idea is to lock the rifle down using the bipod, rear bag, and your firing hand so recoil comes straight back instead of tracking left or right, which makes follow up shots much faster.

It's easiest to learn in the prone. Start by getting comfortable behind the rifle and adjusting your bipod to the proper height. Make sure your body is directly behind the gun your chest, hips, and legs should all be in line. You don't want to be canted off to either side, as that can cause the rifle to recoil diagonally instead of straight back.

With your firing hand on the pistol grip and your thumb wrapped around it, apply firm forward pressure into the bipod to preload it. A solid bipod and mounting system make a big difference here. I first tried it with a Magpul bipod and had a difficult time maintaining consistent preload because of the amount of flex it had. After switching to an Atlas, it was significantly easier to keep steady pressure on the bipod under recoil.

At the same time, cam the buttstock down into your rear bag to lock the rifle down. Make your elevation adjustments with the bag like you normally would, but once you're on target, maintain that forward pressure into the bipod while keeping the stock planted in the bag.

If everything is set up correctly, the reticle shouldn't jump left or right under recoil. Instead, it should move almost straight back and then settle right back on target, making it much easier to spot impacts and get quick follow up shots.

You can use this technique on a barricade or tripod too. As long as you have three solid points of contact, it works.

Here's a video of @Stylz using this technique at ~380 yards

Personally, I've taken a few rifle classes, and this is the first one I've left where it didn't just feel like a refresher of things I already knew. I walked away with a notebook full of new techniques for ranging,  quick dope, reading trace and making fast follow up shots at distance.

If you have the time and resources, I'd highly recommend checking out one of Sidewinder's classes. Adrian does a much better job of explaining these concepts than I ever could.

Originally Posted By Teller_Ulam:

Awesome.  Thank you for the detailed reply! Definitely going to give this a try.

Originally Posted By Sc00t3r:


No problem! It was super satisfying shooting strings on steel at distance, then hearing the impacts come back one after another as each round connected.