IMO, while you're thinking of parts, we need to keep in mind what is happening when we shoot high power rifles. Hint: torqing screws is counter productive. ALL that's going to happen there is stripping threads (if you have the mind to tighten the screws and it still moves, you first inclination is to tighten them more and more and usually the receiver threads wil let go first). Not good.

SO , there's an explosion in the chamber, the interior pressure goes from 500PSi to 5000PSi in .4 seconds. Following physics, the blast will follow the path of least resisitance, in this case ,out the barrel. What's important here is how violent that blast is. IF you watch soldiers in the field, with heavy artillery and watch them fire a charge and the shock wave kicks up the dust all around them for 10 feet. That same thing happens when you fire a round (on a much smaller scale).

When 9/11 happened , it opened a can of worms with physicists and set them on their collective ears (and begat string theory). A phenomenon happens whan a jumbo jet flies into a building at hundreds of MPH- a solid takes on the properties of a liquid. Well, how can that be? Because before that, they thought that moleclues jump from here to there and everywhere, but they do not. What they realized and discovered is that molecules are actually constanly streaming from here to there, back and forth. If we could see it in real time, they're moving so fast, back and forth they look like strings (hence , string theory).

Well us shooters have known that for many many years. That's why we float barrels- because that blast is SO violent the reciever and barrel take on that "liquid properties" thing. The barrel actually whips out there like a wet noodle (and bucks and slaps into the stock and throws the harmonics off and the bullet) and the receiver does too. That shock wave rattles it. So you can torque those screws down until you strip the threads, but it's not going to stop that shock wave from rattlling that reciever and whipping the barrel. IMO, it's akin to, when shooting a pistol, tightening your watch to handle the recoil. So, just like shooting a pistol, we don't even try to STOP the recoil, we try to work WITH the recoil. Back to artillery, Engineers have designed the artillery (and cannons on ships) so that the barrels recoil, to help absorb that shock wave and resulting recoil (for every action there's an equal and opposite reaction) and distribute it along the weapon (ideally evenly), in this case (and with pistols), including your body (why we now get all they way behind the rifle. Back in the day, they got off to the side 45deg.).

So now I hope we can see what we need to do to deal with the explosion and resulting recoil and why just tightening the screws (be it chassis screws or scope screws, too) does nothing. Fact is, the screws are weak in sheer strength, but they're not designed for sheer, they're designed to fasten two things together so that when you're carrying it around, stuff don't fall off. That's it! In fact, it's counter productive, 'cause it interupts the "cycle of the explosion". We can't stop the explosion and shock wave (and don't want to) , but we need to manage it, go with it. In pistol shooting, we call it "riding the recoil". Just like pistol shooting ,we're dealing with TWO things- ONE, that our sights or nothing on the gun moves or changes as we shoot and TWO, the actual shockwave and recoil. So we secure the sights and parts and then we position our bodies and arms so that we can absorb the shockwave and "ride the recoil". We go with it, let it buck, ride it up and then bring it back down to where it was, with the sights lined back up. Same with rifle shooting, so float the barrel, bed the reciever, bed the scope mounts, anything you attach to that rifle, bed it. Why? Because that's the best chance that nothing moves and changes as we shoot and it all can share absorbing the shock wave and recoil. Hope that helps.