All the bubble is doing is pointing out an error, it's not fixing anything in the way most people use them.
In order to FIX the problem, you need to understand the problem. Canting is not something that is automatic, it's not something we all do, it's not something that can't be dialed out with rifle set up. It's mostly new shooters who have an issue because the rifle is improperly set up. Correctly set up a bubble is not needed because the shooter will feel it.
Tell me once how they address the issue when they say you NEED ONE on your rifle. They never explain it because they can't.
In someone's mind, they buy a level, mount it on the rifle, without any regard to their position or set up. They just mount it level and forget about it. Then after you go through your shooter's checklist, before shooting they want you to take your eyes off the target and "check to see if it's level". The only instruction supplied is to look at it.
When the answer is NO, what is the solution, rolling the rifle over back to straight, then returning to the target in order to fire. Now before you all say you are checking shit with your off eye, blah, blah blah, no you are not. Your brain is still focused on it and your mind is not paying attention to anything else because the brain is worried this will ruin your shot. You are nowhere near as good a multitasker as you believe.
On the clock, nobody watches their level I have pictures to prove it, this image, the shooter won the competition, but most of the shots I witnessed were off level, because, you know, the clock.
So you check the level, it's off, you push the rifle straight and shoot. great, 1st round was square. Now you NEED to run the bolt and what did you just do, pull the rifle by the bolt, and cant it again. But now you are in a string of fire, on a clock or whatever, and you stopped checking the level. So 1/2 your shots are off.
New mag, you go through your process, and boom, the level says you are off again. It's not fixing the problem, it's just pointing it out.
I can fix it, I can show you how to adjust the front of the rifle, and the back of the rifle, then to recognize if you tend to pull over the rifle. How much is that worth compared to a $150 level that has 4x less accuracy than the 4 levels in our head?
A bubble is there to help recognize problems in your rifle set up so you can correct them. It's meant to fine-tune your position to find that perfect point of comfort.
In the old days before levels, they actually focused on setting up the rifle correctly vs placing arrows on the rifle to point to bad shit.
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