Do I need a bubble level?

So full disclosure I’m pretty new to all of this, so my experience is limited. But in My opinion you don’t necessarily need a bubble level, but you would be putting yourself at a disadvantage when trying to hold over for elevation. I’ve started putting one on all of my rifles with scopes greater than 1-6. It’s not super expensive nor is it very bulky depending on the model that you get. So I feel it’s a “might as well” kinda thing.
 
I have one set to go on a new build but this thread has me contemplating leaving it off. I have noticed on my current setup that I look at it that first time and rarely check after that. Hmm...probably could have saved that $50.
 
Level should be your natural state. Set the rifle up for you, set the scope level to the world and dryfire in youre living room enough till you know what level looks like. Its really not that hard to get behind the rifle find the target and subconsciously level the reticle. I may not have done as much shooting in crazy places like LL but the mountains are litterally out my back door and theyve never given me any problems.
 
I shoot a monthly match and could not figure why I was always right of most of the shooters. I asked a question here and through tremendous help of the members many good suggestions were offered including cant and the use of a bubble. I am not terribly dense and have done Frank's online videos, setup up my rifle/scope properly, taken several courses and would love to take even more fundamental courses but the simplest $50 level helped me more than anything. It was eye opening to realize our shooting platform was canted enough to throw my 1000 yd shots off enough consistently and once I realized my silly mistake it made all the difference. I wish I had natural skill like Frank but a simple $50 level corrected my silly mistake. A better course or 3 would have certainly fixed it as well but I also enjoy the journey and learning as I go. I get a little better each time I practice or compete. I will never be as good as Frank, Vibbert, Mo, Saterlee whoever but man it sure is fun learning and getting better each week.
 
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7052905


I use a bubble level and it never helps me. Idk why???
 
Chiming back in here to me levels are like any piece of gear. Is it necessary? No. But can if be helpful? Sure. I think I a lot of people do use a level to correct for improper rifle set up and use it as a crutch. Some of those same people will be unable to group on a paper plate at 100 yards yet say, "Oh it must be my barrel," or ,"I need product X". No piece of gear be it chassis, barrel, trigger, etc will help you if you are riddled with bad habits and need experience.

That being said, both of my long range guns have them. Do I check prior to firing yes. Same goes for PRS matches since all it takes is one short half second glance.

Now back to the question of what kind and what do you need well that is all personal preference. A vortex bubble level or accuracy first level (my preference) will get you where you need to be. I don't think you need a $200 send it level.
 
Thanks guys, for all that input, seems I´ve asked "the right question".
:cool:

For now I think a bubble would help me as a beginner to get rid of one more possible problem, just gaining a bit more confidence.

As a right handed shooter, would it be helpful to have the bubble offset on the left?
I´m just thinking, that a bubble on the mount would block my free sight to the elevation turret.

I´m having an ERATAC mount, the manufacturer offers a bubble level for it.
 
There are 3 major reasons for cant. Either the scope was mounted improperly, the rifle is canted because of the bipod, or the shooting surface is uneven and possibly all 3 in some situations. By far the most important is setting the rifle up properly from the get go. If you have done that the other 2 reasons should be easy to overcome with nothing more than fundamentals behind the rifle and using the reticle. It's really that simple.

In this photo that Frank took, which was for our viewing pleasure, the reticle has slight cant to the right. If you are centered behind the rifle properly then this is easy to see without needing a level and you can adjust and lock down the bipod until the shooting position changes. The reticle doesn't lie and if it isn't level from the start the bubble may actually make it worse. You can even out a reticle based on what your eye sees better than a level can because with a level you're now relying on what the bubble is telling you do and not the reticle.
7052972




I took my 120 lb girlfriend who had never shot prone and only shot an AR off a bench at 50 yards shooting last summer at 1000 yards with a 7 SAUM. I set the rifle up and adjusted the cant for the bipod until everything looked straight on target through the scope. Had her get behind the rifle and instructed her step by step in position, breathing and trigger pull. She proceeded to drill the 10" circle at 1000 yards from the first shot, no level needed.
 
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Not sure why the concept is so hard to grasp.

Use level while practicing/training. If you’re constantly having to adjust your cant because the level is telling you so, figure out wtf is wrong and fix it. Eventually you’ll be setting up and won’t need to adjust.

Then you save time in a match as you’re naturally setting up properly and not having to depend on the level.

You can practice trigger control, or you can buy a 4oz trigger and slap it during matches. Same concept here.
 
I think there was a good piece on the podcast that dealt with this and if I recall correctly it's more of a training issue and if you use it prior to each shot it's worth it. What a lot of people do is check once, fire a string without checking again so they end up canting the rifle again.

Need? No. Nice to have? Sure.

@Lowlight may be able to elaborate more /correct me if I'm wrong.

If you have the ability to cant the buttpad with the top angled toward your centerline slightly, that will eliminate some of that "automatic" cant your body puts on the rifle as you mount it.

When I did that I found I rarely needed to look at my bubble level anymore. Everything just seemed to level out naturally.
 
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Thanks guys, for all that input, seems I´ve asked "the right question".
:cool:

For now I think a bubble would help me as a beginner to get rid of one more possible problem, just gaining a bit more confidence.

As a right handed shooter, would it be helpful to have the bubble offset on the left?
I´m just thinking, that a bubble on the mount would block my free sight to the elevation turret.

I´m having an ERATAC mount, the manufacturer offers a bubble level for it.
All personal preference. I have mine in front of my elevation turret. Sure I can only see the top edge to a little past center but that's all I care about. I'd personally go with one offset to the left if you're a right hand shooter.

7052981
 
Let me restate from a PRS perspective. It’s pretty widely accepted that your head is used as a counterweight to balance, especially in unnatural positions. PRS is based on shooting in many unnatural positions. So when you put your bag on a rock that isn’t flat, and you’re standing awkwardly behind your rifle due to terrain, you use your head to counterbalance to keep yourself from falling over (think the rocks at K&M or CORE). Your head is no longer perpendicular to gravity, it’s canted for balance. You need a level as a constant, because you aren’t always in a position to have your head be perfectly straight up. If the $30 for a level is too much for you, you’re in the wrong game. But be my guest, I’ll take all the points you want to give me, Lord knows I need em.
 
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I asked for it, because I have no clue.

I don´t fear the money to spend at all, but I don´t want to waste my time with stuff no one needs.
Ordering a bubble right away now, the Lord knows for sure, that I need the points more than you do.

Cheers!
 
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I asked for it, because I have no clue.

I don´t fear the money to spend at all, but I don´t want to waste my time with stuff no one needs.
Ordering a bubble right away now, the Lord knows for sure, that I need the points more than you do.

Cheers!

My comment wasn’t directed toward you at all...more toward the folks who don’t see the value of a level, particularly in PRS. :)
 
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Enjoy a chuckle at my expense. I just bought a scope level. I’m new to this pursuit. I’ve put forth some thought and effort setting up my rifle to me. Length of pull, eye relief, reticle focus, trigger pull weight, cheek piece height. Also been practicing fundamentals dry firing. Scope is in a Spuhr mount, level to the rifle, reticle is level to a plumb bob. I’m right handed and consistently notice bubble level indicates a right can’t. I’m gonna rotate the scope to “my” NPA position and try it. Appreciate the info shared here.
 
I can say as a total noob with 1 match under my belt, that I even forgot that I had one while shooting stages.
I use it at the range while practicing and working up loads, but never once looked at it while shooting the match. I'm sure I missed a lot of things that hurt my score, but I don't feel that the level was one of them.
I worked the timer for a couple of stages too and and can say that I don't recall anyone looking at their level.
 
In PRS you have absolutely no time to check level

90 seconds is not enough, and their ranges are super short to begin with ... the average PRS range is between 400 and 600 yards on a 2 MOA target, if you cannot hold that, get a new hobby

More BS from the peanut gallery trying to justify spending people's money, misery loves company

I've been shooting for decades, and never used levels until a few years ago. I started using them for PRS because I found that while shooting from awkward positions on uneven surfaces and with a crooked horizon or no horizon in view, there were times that I thought I was level....and wasn't. I set them up so that I can see them with my left eye without breaking position (takes very little time). For many stages, I don't even glance at the level at all, but for some it's useful. Also, I don't know where these 400-600 yard PRS matches are, but all of the ones in my region go to at least 800, and most over 1,000. My answer to the O.P. would be: necessary? No. Useful in some situations? Yes. I find they are especially useful when using a new rifle with a different type of stock, until you get accustomed to the fit and feel of the new rifle.
 
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Pictures like the one Frank took above make me laugh my ass off. Sure, if that’s where you shoot, save the 50 bucks and check level based on your reticle against the horizon.

Hunt where I do... where Nothing is flat and Nothing is vertical and No shooting position is flat or in any way standard. All the shots are either uphill or down hill at an angle to the slope of the mountain.

Your rifle WILL be canted. I’ll put money on it.

31470239-75DD-439E-8598-1F1600FBB4BE.jpeg




There are 3 major reasons for cant. Either the scope was mounted improperly, the rifle is canted because of the bipod, or the shooting surface is uneven and possibly all 3 in some situations. By far the most important is setting the rifle up properly from the get go. If you have done that the other 2 reasons should be easy to overcome with nothing more than fundamentals behind the rifle and using the reticle. It's really that simple.

In this photo that Frank took, which was for our viewing pleasure, the reticle has slight cant to the right. If you are centered behind the rifle properly then this is easy to see without needing a level and you can adjust and lock down the bipod until the shooting position changes. The reticle doesn't lie and if it isn't level from the start the bubble may actually make it worse. You can even out a reticle based on what your eye sees better than a level can because with a level you're now relying on what the bubble is telling you do and not the reticle.View attachment 7052972



I took my 120 lb girlfriend who had never shot prone and only shot an AR off a bench at 50 yards shooting last summer at 1000 yards with a 7 SAUM. I set the rifle up and adjusted the cant for the bipod until everything looked straight on target through the scope. Had her get behind the rifle and instructed her step by step in position, breathing and trigger pull. She proceeded to drill the 10" circle at 1000 yards from the first shot, no level needed.
 
Pictures like the one Frank took above make me laugh my ass off. Sure, if that’s where you shoot, save the 50 bucks and check level based on your reticle against the horizon.

Hunt where I do... where Nothing is flat and Nothing is vertical and No shooting position is flat or in any way standard. All the shots are either uphill or down hill at an angle to the slope of the mountain.

Your rifle WILL be canted. I’ll put money on it.

View attachment 7056795

Gee how do you walk and not fall down, I live in CO and shoot in the mountains, still won’t use it if you can’t feel it, try fixing that

Wonder how people hunted before levels were a thing, in fact prior to 2005 how did we accomplish and successfully shoot or hunt

Funny we used to shoot these matches before the PRS existed way back in 2011, no levels. Ask yourself this question, what’s the longest running match of this kind still going on today
 
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Lowlight,

We walked before boots but they help and now YOU use them... not because you couldn’t get by without them, but because they definitely help.

We hunted and shot before magnified optics but optics help so YOU use them... not because you couldn’t get by without them but because they definitely help.

I could go on for days or until banned...
 
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I shot Gunsite this past week, XLR course, no level, no issue.

Distances, hills, no horizon at times, wonder how we managed that feat

7056861


Guys say you need to dial SD and CE at these ranges too, not me, in fact I watched guys dial on .6 to .8 Mils inside these ranges then have to hold on the wrong side of the wind, some might call it a clue but others continue to bang the drum it’s not only necessary but you can’t hit without it. Me, I dope the wind and my hits never suffered. In fact the only time my wind calls suffered was when I tried calling wind for guys with too much dialed on.

I guarantee if these defenders posted images of them shooting in these conditions we can find 4 things wrong in about 3 seconds
 
Lowlight,

We walked before boots but they help and now YOU use them... not because you couldn’t get by without them, but because they definitely help.

We hunted and shot before magnified optics but optics help so YOU use them... not because you couldn’t get by without them but because they definitely help.

I could go on for days or until banned...

Not everything helps, not everyone uses it and new does not always mean better,

Like others have posted, crutches exist doesn’t mean we need them to walk.

Technology can be a double edge sword, some tech helps other tech gets in the way.

In fact new study says mental health has suffered since the widespread use of smartphones, so sure you can do it all day, as can I, sometimes unplugging is not a bad thing.

Learn the correct way, not a shortcut aided by a crutch
 
@Evolution 9

Plus how far you really shooting with that hunting rifle in that picture, maybe 300, 400 if the animal is big enough, how much can’t do you think will go unnoticed before you actually see an issue.

You’d have to be rolled over 5+ degrees at those short ranges and if you can’t resolve less than 2 degrees without a level you have a personal problem. A bubble level is barely .8 degrees accurate between the lines. You are not resolving very tight, the sub 1 degree you might be off from the ground is irrelevant it’s a blown 1 MPH wind from guys that can barely manage 3 MPH of success.
 
Nobody could or would question your skills. And nobody sane would say that a level is absolutely necessary.

For the vast majority of shooters in my terrain, a level is very helpful for longer shots.

You not accounting for SD and CE doesn’t mean they aren’t affecting your results in fact, it’s an undeniable fact that they are. It just means you’re enough better at wind calls than most guys that the net affect of ignoring those two and nailing your wind call is better than nailing those two and being way off on wind call.

This no doubt also reduces any (real or perceived) need on your part for a level.


That’s my buddy in the pic, not me. I took the picture. I use entirely different gear and methods (and don’t take my dog elk hunting) ?

My last shot hunting was 1070 yards. Plenty long for minor cant to make a real difference.
 
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It means the numbers are mostly wrong, the computers were giving them the .6 & .8 adjustment which guys take as gospel. Fact is the effects are tiny just like the need for a level. .3 is close to right at 2000 yards vs using .8 at 1500. We explored this and the numbers, clearly there is a disconnect. Plus Coriolis is Macro not micro. We have mechanical fixes for SD yet we never went that way over 100 plus years. It’s a 1.25% issue.

Every example of why you need one uses 5 degrees off can’t, 5 is huge and if you can’t resolve it, you have a problem. You’re being sold a lie in the name of capitalism. A 5 degree example with a tool with barely .8 degree of accuracy, most can see 2 degrees with the naked eye, but when lulled into a sense of security because they mounted a level, the same shooter will miss it.

I shoot in a variety of conditions with all kinds of people, including those who feel you need to include it. I have yet to be convinced and in fact the more I experience the varying arguments the more I think they are self serving

1079 yards means you have time and opportunities to set the shot up right and not can’t.
 
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I'll chime in I guess.

Shooters tend to strap needless things to their rifles, thinking that they will help them gain an edge...or in reality, just do it because they saw it on IG/FB/YT. Most don't know how to set their rifle systems up properly, let alone know how to accurately read wind or collect data. So what Frank is saying makes sense if you stop and take an objective look. The car mirror analogy is a perfect way to break it down. Combine improper fundamentals with an inability to accurately make wind calls and you end up stacking more problems that ultimately a bubble in water cant fix.

Use one for training yourself but don't rely on extra equipment. Take a look at something like the Accuracy 1st level. A lot of shooters own one or a similar scope body-mounted level. How many times do you check that it hasn't been moved in storage/transport prior to use? Throw it in a drag bag or gunslinger and being that it is a piece of aluminum wrapped around a piece of aluminum with a lever sticking out, how often do you think it gets bumped? How many times until it starts to creep slightly off? Now when you plop down behind the rifle, you see the cant is slightly off so you adjust. Now you've been relying on this device to correct your improper fundamentals and actually start to impose a slight cant.

End of the day, fundamentals are key. No piece of equipment will ever replace the fundamentals of marksmanship. Train your weaknesses. My weakness? Sour Patch Kids and shooting support side. :D
 
Regardless of your position on levels, there’s been a lot of straw man arguments thrown around the last two pages.

“Most examples of cant are 5 degrees” — not my problem what someone else uses as their example

“Most people don’t set them up correctly or verify that they’re level” — no, and same could be said of those people’s scopes, you gonna ditch your scope because some people use theirs wrong?

And a few others.

I’ll again admit that most of my shooting life I have gotten by just fine without a level.
 
I'll chime in I guess.

Shooters tend to strap needless things to their rifles, thinking that they will help them gain an edge...or in reality, just do it because they saw it on IG/FB/YT. Most don't know how to set their rifle systems up properly, let alone know how to accurately read wind or collect data. So what Frank is saying makes sense if you stop and take an objective look. The car mirror analogy is a perfect way to break it down. Combine improper fundamentals with an inability to accurately make wind calls and you end up stacking more problems that ultimately a bubble in water cant fix.

Use one for training yourself but don't rely on extra equipment. Take a look at something like the Accuracy 1st level. A lot of shooters own one or a similar scope body-mounted level. How many times do you check that it hasn't been moved in storage/transport prior to use? Throw it in a drag bag or gunslinger and being that it is a piece of aluminum wrapped around a piece of aluminum with a lever sticking out, how often do you think it gets bumped? How many times until it starts to creep slightly off? Now when you plop down behind the rifle, you see the cant is slightly off so you adjust. Now you've been relying on this device to correct your improper fundamentals and actually start to impose a slight cant.

End of the day, fundamentals are key. No piece of equipment will ever replace the fundamentals of marksmanship. Train your weaknesses. My weakness? Sour Patch Kids and shooting support side. :D
Nailed it!
 
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The level is a bandaid. While it can be useful as a training tool, it shouldn’t be relied on. Half the time it is a distraction from what you need to be focusing on. You should rely on your position and fundamentals. In international/Olympic type shooting this is referred to your inner position. Do we use levels? Sure. But I can tell you that the position is off most times before I even have the chance to look at the level to see that it is not centered.

Lowlight has gone over this countless times and it has been confirmed over and over. The more you trust the level as an end all be all solution to chanting the rifle, the more and more you’ll go down a rabbit hole of bandaids before finding out it is the position and you that needed fixing all along.
 
I'll chime in I guess.

Shooters tend to strap needless things to their rifles, thinking that they will help them gain an edge...or in reality, just do it because they saw it on IG/FB/YT. Most don't know how to set their rifle systems up properly, let alone know how to accurately read wind or collect data. So what Frank is saying makes sense if you stop and take an objective look. The car mirror analogy is a perfect way to break it down. Combine improper fundamentals with an inability to accurately make wind calls and you end up stacking more problems that ultimately a bubble in water cant fix.

Use one for training yourself but don't rely on extra equipment. Take a look at something like the Accuracy 1st level. A lot of shooters own one or a similar scope body-mounted level. How many times do you check that it hasn't been moved in storage/transport prior to use? Throw it in a drag bag or gunslinger and being that it is a piece of aluminum wrapped around a piece of aluminum with a lever sticking out, how often do you think it gets bumped? How many times until it starts to creep slightly off? Now when you plop down behind the rifle, you see the cant is slightly off so you adjust. Now you've been relying on this device to correct your improper fundamentals and actually start to impose a slight cant.

End of the day, fundamentals are key. No piece of equipment will ever replace the fundamentals of marksmanship. Train your weaknesses. My weakness? Sour Patch Kids and shooting support side. :D

I’ve had too much crap spin in scope tubes...
Use a spuhr mount and mark the scope to ring junction. (y)
 
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Canting is for real, it does have an effect on both the vertical and horizontal. As an example, a .308 Win at 1000 with a barely perceptible 2° cant to the right, will move the POI about 15" to the right and 0.26" low (1.4 and 0.03 MOA). At 1500 you get 50" right and 0.9" low (3.2 and 0.06 MOA). To dimension this, 1 minute on a clock's face represents a 6° cant, thus making a 2° cant very hard to tell apart or next to impossible. Having said this, do I use a level? No. But at long range, it's very easy to mistakenly take this for wind, etc.
 
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Canting is for real, it does have an effect on both the vertical and horizontal. As an example, a .308 Win at 1000 with a barely perceptible 2° cant to the right, will move the POI about 15" to the right and 0.26" low (1.4 and 0.03 MOA). At 1500 you get 50" right and 0.9" low (3.2 and 0.06 MOA). To dimension this, 1 minute on a clock's face represents a 6° cant, thus making a 2° cant very hard to tell apart or next to impossible. Having said this, do I use a level? No. But at long range, it's very easy to mistakenly take this for wind, etc.

This is simply not true. You would have to be canted at least 20 degrees to the right to be off 15" at 1k with a .308. In fact spin drift would have more of an effect at that distance then a 2 degree cant to the right.
 

Trajectory
Input Data
Ballistic Coefficient:0.233 G7Caliber:0.308 in
Bullet Weight:168.0 gr
Muzzle Velocity:2650.0 ft/sDistance to Chronograph:10.0 ft
Sight Height:1.50 inSight Offset:0.00 in
Zero Height:0.00 inZero Offset:0.00 in
Windage:0.000 MOAElevation:0.000 MOA
Line Of Sight Angle:0.0 degCant Angle:20.0 deg
Wind Speed:0.0 mphWind Angle:90.0 deg
Target Speed:10.0 mphTarget Angle:90.0 deg
Target Height:12.0 in
Temperature:59.0 °FPressure:29.92 in Hg
Humidity:0 %Altitude:0.0 ft
Vital Zone Radius:5.0 in
Std. Atmosphere at Altitude:NoPressure is Corrected:Yes
Zero at Max. Point Blank Range:NoTarget Relative Drops:Yes
Mark Sound Barrier Crossing:NoInclude Extra Rows:No
Column 1 Units:1.00 inColumn 2 Units:1.00 MOA
Round Output to Whole Numbers:No
Output Data
Elevation:3.905 MOAWindage:0.000 MOA
Atmospheric Density:0.07647 lb/ft³Speed of Sound:1116.4 ft/s
Maximum PBR:322 ydMaximum PBR Zero:273 yd
Range of Maximum Height:151 ydEnergy at Maximum PBR:1589.0 ft•lbs
Sectional Density:0.253 lb/in²
(yd)(in)(MOA)(in)(MOA)(ft/s)(none)(ft•lbs)(s)(in)(MOA)
RangeDropDropWindageWindageVelocityMachEnergyTimeLeadLead
Calculated Table
0-1.4***-0.5***2656.62.3792632.20.0000.0***
100-0.2-0.10.90.82463.42.2062263.30.11720.619.7
200-4.6-2.22.31.12278.42.0411936.10.24442.920.5
300-15.8-5.03.71.22101.81.8831647.60.38167.121.3
400-34.9-8.35.11.21933.31.7321394.00.53093.322.3
500-63.3-12.16.51.21771.61.5871170.60.692121.823.3
600-102.9-16.47.91.31616.21.448974.30.869153.024.3
700-155.7-21.29.31.31466.91.314802.61.064187.325.5
800-224.8-26.810.71.31324.41.186654.21.279225.226.9
900-313.8-33.312.11.31190.31.066528.41.518267.228.4
1000-427.5-40.813.51.31078.70.966434.01.784314.030.0
 
I don’t think your data is calculating the cant. The majority of your horizontal component with that 308 is spin drift. Try the formula from the published research paper.
 
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I’m very curious of the dogmatic approach of a few folks in this thread. You don’t need a level because “xyz” or “I don’t use a level and it’s not an issue.” Can the rest of us assume you shoot every match clean? You don’t miss? Furthermore how would you know if you missed a shot due to cant if you don’t have a level for reference? As I said before, far too many examples of shooters missing due to cant and blaming it on wind shift.
 
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I calculated the spin drift separately and it worked out to be 11.9" right with all other values being the same. Adding the spin drift and 20 degree cant adjusted the windage to 25".

All I'm saying is despite what the math says, I must be better than I thought at eliminating cant without a level because like someone said, 2 degrees is hardly perceptible and I have never observed anything close to a 15" disparity at 1k.
 
I’m very curious of the dogmatic approach of a few folks in this thread. You don’t need a level because “xyz” or “I don’t use a level and it’s not an issue.” Can the rest of us assume you shoot every match clean? You don’t miss? Furthermore how would you know if you missed a shot due to cant if you don’t have a level for reference? As I said before, far too many examples of shooters missing due to cant and blaming it on wind shift.

Because I trust what I see on the targets that's why. And by the way, just .030 of movement on that bubble causes a 2 degree cant in either direction. Anyone who says they are keeping a bubble from shifting or centering it for that matter while maintaining proper shooting technique is just lying to themselves.
 
Because I trust what I see on the targets that's why. And by the way, just .030 of movement on that bubble causes a 2 degree cant in either direction. Anyone who says they are keeping a bubble from shifting or centering it for that matter while maintaining proper shooting technique is just lying to themselves.

Are you speaking from a PRS perspective or belly shooting?
 
I calculated the spin drift separately and it worked out to be 11.9" right with all other values being the same. Adding the spin drift and 20 degree cant adjusted the windage to 25".

All I'm saying is despite what the math says, I must be better than I thought at eliminating cant without a level because like someone said, 2 degrees is hardly perceptible and I have never observed anything close to a 15" disparity at 1k.
I don't get your reasoning. Do you believe or not in the math? On the other hand, JBM does calculate cant ONLY at the zero range. Run it again with a ZR at 1000. What you got before was CANT at 100 yards and after that an angular deflection.

So, check out the following tables by JBM at 1000 and at 1500 both cases with a 2° CANT :)

Trajectory
Input Data
Ballistic Coefficient:0.233 G7Caliber:0.308 in
Bullet Weight:168.0 gr
Muzzle Velocity:2650.0 ft/sDistance to Chronograph:10.0 ft
Sight Height:1.50 inSight Offset:0.00 in
Zero Height:0.00 inZero Offset:0.00 in
Windage:0.000 MOAElevation:0.000 MOA
Line Of Sight Angle:0.0 degCant Angle:2.0 deg
Wind Speed:0.0 mphWind Angle:90.0 deg
Target Speed:10.0 mphTarget Angle:90.0 deg
Target Height:12.0 in
Temperature:59.0 °FPressure:29.92 in Hg
Humidity:0 %Altitude:0.0 ft
Vital Zone Radius:5.0 in
Std. Atmosphere at Altitude:NoPressure is Corrected:Yes
Zero at Max. Point Blank Range:NoTarget Relative Drops:Yes
Mark Sound Barrier Crossing:NoInclude Extra Rows:No
Column 1 Units:1.00 inColumn 2 Units:1.00 MOA
Round Output to Whole Numbers:No
Output Data
Elevation:44.498 MOAWindage:0.000 MOA
Atmospheric Density:0.07647 lb/ft³Speed of Sound:1116.4 ft/s
Maximum PBR:322 ydMaximum PBR Zero:273 yd
Range of Maximum Height:151 ydEnergy at Maximum PBR:1589.0 ft•lbs
Sectional Density:0.253 lb/in²
(yd)(in)(MOA)(in)(MOA)(ft/s)(none)(ft•lbs)(s)(in)(MOA)
RangeDropDropWindageWindageVelocityMachEnergyTimeLeadLead
Calculated Table
0-1.5***-0.1***2656.62.3792632.20.0000.0***
10042.540.61.61.52463.32.2062263.20.11720.619.7
20080.738.53.21.52278.22.0411935.90.24442.920.5
300112.335.74.81.52101.61.8821647.40.38167.121.3
400135.932.46.51.51933.01.7311393.70.53093.322.3
500150.228.78.11.51771.41.5871170.30.692121.823.3
600153.424.49.71.51615.91.447973.90.869153.024.4
700143.319.511.31.51466.61.314802.21.064187.325.6
800116.914.013.01.51324.01.186653.81.279225.226.9
90070.67.514.61.51189.91.066528.01.519267.328.4
1000-0.4-0.016.21.51078.40.966433.71.784314.130.0
07-Apr-19 19:05, JBM/jbmtraj-5.1.cgi


(yd)(in)(MOA)(in)(MOA)(ft/s)(none)(ft•lbs)(s)(in)(MOA)
RangeDropDropWindageWindageVelocityMachEnergyTimeLeadLead
0-1.5***-0.1***2656.62.3792632.20.0000.0***
100100.095.53.63.42463.22.2062263.00.11720.619.7
200195.793.47.23.42278.02.0401935.50.24442.920.5
300284.790.610.83.52101.31.8821646.80.38167.121.4
400365.887.314.53.51932.61.7311393.00.53093.322.3
500437.683.618.13.51770.81.5861169.60.692121.823.3
600498.279.321.83.51615.31.447973.20.870153.124.4
700545.574.425.43.51465.91.313801.51.065187.425.6
800576.668.829.03.51323.21.185653.11.280225.326.9
900587.762.432.73.51189.01.065527.31.519267.428.4
1000574.154.836.33.51077.80.965433.21.785314.230.0
1100530.946.139.93.51023.50.917390.72.072364.631.7
1200454.536.243.63.5984.00.881361.12.371417.233.2
1300342.225.147.23.5949.40.850336.22.681471.934.7
1400191.313.050.83.5917.60.822314.13.003528.536.1
1500-1.0-0.154.53.5887.90.795294.03.336587.137.4
 
This is simply not true. You would have to be canted at least 20 degrees to the right to be off 15" at 1k with a .308. In fact spin drift would have more of an effect at that distance then a 2 degree cant to the right.
No, it's 100% right on the money. Do your math again and before anything else, check out some papers on the math of cant. It's there and with such a magnitude, despite we like it or not. If you don't see it is simply because you are doing right your fundamentals.

Yes, SD, Cant, Wind, etc...all part of the bitch of LR work ;)
 
Because I trust what I see on the targets that's why. And by the way, just .030 of movement on that bubble causes a 2 degree cant in either direction. Anyone who says they are keeping a bubble from shifting or centering it for that matter while maintaining proper shooting technique is just lying to themselves.
Perhaps you still don't fully grasp the mechanics of cant and how much damage can do to our shooting, even with very tiny angles, it's just a fact that most shooters don't fully realize. On levels, I concur with your opinion.