Does it necessary to use a scope bubble level for a pcp airgun ?

I have three levels on the way for my Condors. Since these are long range guns, canting really makes a difference, one will go on my 22 Condor SS as it is a bench and field gun, one of my other two Condors is a field/bench gun and the other is a Bench Varmint gun, both those are .25 cal. ... I think I will put a Mueller 8x32 on that gun.

wll2506
 
If you want to do an easy test set up your 50 yard target with a plumb bob just in front of the target. you can then cant your rifle but keep the dot on the target center. I have shot the string playing with this lol. and see what the cant does at 50 yards. If you shoot at 100 yards then set up your 100 yard target and do the same test.

I also at times use poster board and a 4 ft level at 50 yards so I know the vertical and horizontal lines are level and plumb. its the way I set up scopes sometimes.

I do have the bubble level on a couple of my rifles.
 
When I started shooting the Bobcat MK2 I had a devil of a time with cant. I used a wheeler scope mounting kit that I have used on all my rifles but during the shooting especially with the high FX adjustable mounts I found myself inducing cant into the rifle. I double checked my rifle setup again and used a plumb bob with a brightly colored green string at 15 yards and everything was dead on. At the bench with the chronograph I noticed I was twisting the rifle left or right so I put a bubble on the rifle. Problem solved...
During my shooting at the longer range that induced cant is really magnified and will throw your shot off. So I am sold on mounting a bubble level on all your rifles.
Also I have noticed using a set of shooting sticks or swivel rest during my hunting trips that I pay closer attention to the bubble level prior to the shot and have improved my shot placement dramatically. Never a problem when I was younger and shooting iron sights but with the higher mounts, a powerful scope and age catching up with me I use whatever it takes to improve my odds. 
 
Gentelmen ,

Take this for what it's worth.. Bubble levels are not created equal. Especially the little bubble levels you get like with pictures hangers and such. Don't just assume that the bubble in the center of the lines is true level because the casing can be off a bit. A quick test is to check it by switching it 180 degrees and seeing where the bubble lands. I've had levels land center one way then spin it 180 and on the line the other way. Use the same exact surface and location when doing this. You may be surprised.... 

T.J.
 
"EXZIVER"Gentelmen ,

Take this for what it's worth.. Bubble levels are not created equal. Especially the little bubble levels you get like with pictures hangers and such. Don't just assume that the bubble in the center of the lines is true level because the casing can be off a bit. A quick test is to check it by switching it 180 degrees and seeing where the bubble lands. I've had levels land center one way then spin it 180 and on the line the other way. Use the same exact surface and location when doing this. You may be surprised.... 

T.J.
Yes i've also seen this.