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I watched four YouTube vids about them,
But all the vids were about people shooting at 775 yd. to 1300 yd. distances with giant, powerful ammo.

My question is
Would they be advantageous for rifles
that are half as powerful,
Shooting targets at half the distance ?

Example :
Instead of .50 cal. at 1400 yds.,

Maybe .243 win. cal. at 400- 550 yds.

I realize that barrels, ammo, scopes and shooters ability enter the equation .

Just curious, no intention in of precession shooting.
Thanks for
Any attention you give this





Safety, Situational Awareness and proficiency.



Neck Ties, Hats and ammo brass, Never ,ever touch'em w/o asking first
 
Posts: 51677 | Location: Henry County , Il | Registered: February 10, 2004Reply With QuoteReport This Post
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Couldn't hurt! Big Grin

They make them for iron sighted rifles as well.. probably for a lot longer than they've made them for scopes.


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Posts: 18407 | Location: 18th & Fairfax  | Registered: May 17, 2003Reply With QuoteReport This Post
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First, the disclaimer: I have a tendency to load up my precision rifles with accessories because I can rather than because I have or even anticipate a definite need for them. The cosine angle indicator on one rifle is one example even though I know I’ll almost certainly never use it for its intended purpose.

I have bubble levels on all of the rifles I use for precision shooting, and that even includes the 22 Long Rifle Ruger 77/22. I always use them when shooting, but partly because of the discipline they help instill when getting into shooting positions. They help remind me, “Yes, do all the things you’re supposed to.”

Are they really necessary, though? The ballistician Bryan Litz thinks so. He contends that without a leveling device of some sort human beings are incapable of estimating small angular cants. I also confirm that for myself all the time. When I get into position and then check the level, I almost always have to adjust the angle of the rifle.

But to address your question, we need to know when a canted gun will have enough effect on the bullet trajectory to matter. I have thought of trying to calculate that myself, but I don’t have the instruments to make it easy, and for other reasons have just never gotten around to it. We do know that small movements of the gun have large effects down range. Think of a drawing protractor of the sort children used back when they were taught about numbers and angles. A one degree increment on most protractors is very small; for example on a 6 inch protractor it subtends about 0.1 inch. Now divide that by 60 to get a minute of angle. And yet at 400 yards, a minute of angle covers about 4.2 inches.

On the other hand, leveling devices are relatively new in the shooting sports. With the exception of the type of iron target sights cas referred to, I still remember about when I first became aware of them for telescopic sights. They have proliferated greatly in recent years, but for decades hunters, target shooters, and military and law enforcement snipers did without them.

As I say, they help me with my shooting discipline. As indicated, they are also more important for long range shooting, and the height of the sight above the bore line also makes a difference. The iron sights of my M1A are about 1 inch above the bore line; canting that gun when firing will have much less effect than the same degree of cant with my Tikka whose sight line is 2.7" above the bore.

Added: I did a little online research and ran across a good article that explains not only why and how canting the gun affects the point of impact, but also included the author’s range reports. Using a rifle chambered for 260 Remington, he zeroed the rifle at 400 yards and fired groups at that distance. Canting the rifle just 5° had a significant effect on the point of impact at that distance. Not only was the horizontal POI changed, so was the vertical.

“I went out to my local shooting range and zeroed the rifle at 400 yards when ScopLevel #1 read level. I shot several groups to be sure of the zero. Next, I rotated the rifle until ScopLevel #2 read level. This produced a cant of 5°. I shot several groups at 400 yards with the canted rifle, and measured the effects each time.

“The results? Surprising, to say the least. When canted, the bullets struck about 4 inches to one side. I expected some horizontal movement. But I did not expect the vertical movement to be as large as it was — the vertical impact averaged 3.75 inches low!”


LINK

Bryan Litz states that the average person cannot detect an angular change of less than 3°, and I suspect that’s being generous for most of us. I have Spuhr bubble levels mounted on several of my guns and based on an online calculator I used, tilting the level so that the edge of the centered bubble moves about 1 millimeter to the calibration line on the tube is an angular difference of a bit over 4°. That is such a small tilt that without the level I’m sure I couldn’t detect or correct for it under field conditions unless I had something like the edge of a building to view it against. On the other hand, with the level, I routinely correct for that degree of cant.

Anyway, thanks for the question. It prompted me to research the issue and now I have a much better understanding of it myself.

This message has been edited. Last edited by: sigfreund,




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Posts: 43679 | Location: 10,150 Feet Above Sea Level in Colorado | Registered: April 04, 2002Reply With QuoteReport This Post
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Thanks for taking the time to respond.

I guess the next thing to know would be the use of the word precession .

Precise for a .243 win and for precise for .30-06 might be two different
descriptions.

I wonder if there are 5 websites for 5 different calibers of precession shooting ?





Safety, Situational Awareness and proficiency.



Neck Ties, Hats and ammo brass, Never ,ever touch'em w/o asking first
 
Posts: 51677 | Location: Henry County , Il | Registered: February 10, 2004Reply With QuoteReport This Post
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“Precession” or precision? Wink

It’s only been in relatively recent times that I’ve noticed shooters’ making a distinction between precision and accuracy. At one time, and still to a large extent, “accuracy” referred to the ability of a gun to put all its shots close together. I.e., it produced small groups, without regard to how closely they clustered to the point of aim. That’s obviously what Townsend Whelen was referring to when he said, “Only accurate rifles are interesting.” It’s also how I interpreted the word for most of my life when referring to firearms.

In recent years, however, many shooters prefer to use “accurate” to refer to how closely the bullets strike with respect to the point of aim, and “precise” refers to how small the groups are without regard to where they are located with respect to the point of aim.







In the above illustrations the centers of the circles were the points of aim and the × marks are where the bullets hit. In the modern shooter’s lexicon, the upper left group is precise and accurate. The upper right group is accurate, but not precise. The lower left group is precise but not accurate. The lower right group is neither precise nor accurate.

Precision and accuracy are of course relative terms. If all my shots from a handgun strike the 4-inch circle in the center of the head of an IDPA target at 15 yards, I would probably be satisfied from the standpoints of both precision and accuracy. If, however, I were shooting my 6.5 Creedmoor Tikka rifle from a bench, I would expect that level of both at 400 yards.

Some cartridges have long enjoyed the reputation of being more precise than others. Even if we were using ammunition prepared to the same level of care and the same quality of barrel and other rifle components for both, I would expect better long range results when shooting the 6.5 Creedmoor than the 257 Roberts. In practice, though, reputations for “inherent” precision will always be influenced to a degree by variables such as the quality of suitable bullets and the types of rifles the cartridges are chambered for. If shooters and handloaders had expended as much effort on improving the precision of the 243 Winchester cartridge over the years as the 30-06 Springfield, would it have the same reputation? That we don’t know because it hasn’t occurred (to my knowledge). It’s possible, therefore, that the shooter of rifles chambered for 243 and 30-06 might be satisfied with groups fired from the former that would disappoint him if fired from the ’06.




“To argue with a person who has renounced the use of reason is like administering medicine to the dead.”
— Thomas Paine
 
Posts: 43679 | Location: 10,150 Feet Above Sea Level in Colorado | Registered: April 04, 2002Reply With QuoteReport This Post
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I have em on my benchrest rifle scopes.
I also do allot off checking with another level.

If you ever used a holographic site it'll show you what the smallest cant of a rifle will do to poi.

On a hunting rifle ...maybe it can help you learn to hold level.
 
Posts: 961 | Location: Mint Hill NC | Registered: November 26, 2016Reply With QuoteReport This Post
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^^^ This just follows long standing terminology used in metrology in industry. It would be interesting to shoot a statistically significant number of rounds (>30) from a machine rest and do an actual capability study.
 
Posts: 2666 | Location: Indiana | Registered: December 28, 2004Reply With QuoteReport This Post
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quote:
Originally posted by Haveme1or2:
I also do allot off checking with another level.


How do you do that?
 
Posts: 43679 | Location: 10,150 Feet Above Sea Level in Colorado | Registered: April 04, 2002Reply With QuoteReport This Post
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I have bubble levels on most of my scoped rifles, but there is much more to bubble levels than most people know (to be fair) or care about.

Bubble levels are used to detect and show the inclination that may be present when you are aiming your rifle. In a long range situation, at 1000 yards, one degree of cant gives about 6 inches of lateral displacement and there is some drop in elevation also.

As you would expect, I am finicky about the level I have on my F-TR match rifle, which I shoot most often at 1000 yards. I have been through various models of levels and I for the last 6 months or so, I finally settled on my current model.

A bubble or spirit level is made in a way that the internal space is shaped like a barrel. You may also see that on the outside, but it's difficult to tell sometimes. The principle of operation is that the bubble in the fluid (usually ethanol) looks for the highest spot in the barrel. If the tube was straight, you could not use the level as it would indicate nothing reliable. The quality of a level is its sensitivity. This sensitivity is varied by the radius of the barrel shape, so to speak. You measure the sensitivity of a level by the amount of cant that is required to move the bubble 2mm. When the radius of the barrel is large, the sensitivity is low. Conversely, when the radius is smaller, the sensitivity is correspondingly higher.

So, let's say that your level requires an inclination of 30 MOA (or 0.5 degree) to move the bubble 2mm. That is its sensitivity. Some people refer to this type of level as a 30 minute level. Another level may require a 60 MOA (or 1.0 degree) to move the bubble 2mm. That is sometimes referred to as an hour (60 minutes) level. That level is not as sensitive as the 30 minute level. On the other hand you can have a level that only requires 15 MOA (or .25 degree) to move the bubble 2mm.

Now, most levels used in shooting are the less sensitive one and I kinda like a little more sensitivity without going overboard.

I have had levels that had their bubble break up and it's disconcerting to watch that and try to figure out what's what. I won't mention the brand name of that crappy Vortex product, but I got rid of it. The size of the vial is important also, along with its visibility. I find the levels built into mounts to be near-useless as they are too small and insensitive for my needs. I always place my levels on the left side of the scope, where I can read them with my left eye as I'm aiming

Let me state that at the beginning of a string, I will lock down the bipod and make sure the rifle is level. During the string, it will not cant much, but I do keep an eye on the level, usually. If I shot goes low and right or low and left, I check the level, to be sure. There have been a few cases where the rifle had canted a bit because I had not locked it completely. It happens and that's why I have a level on it, and a sensitive one at that.

My other rifles have Holland levels and I like those also. I've had other ones beside my current ones and the crappy Vortex, but I let all those go over the years. I'm sure there are other good ones out there but I'm happy with my current ones. There is talk about having electronic levels in scopes. That's already a thing, but I'm old-fashioned.
 
Posts: 3216 | Location: Texas | Registered: June 20, 2012Reply With QuoteReport This Post
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quote:
Originally posted by sigfreund:
quote:
Originally posted by Haveme1or2:
I also do allot off checking with another level.


How do you do that?

I shoot benchrest. The stock's are flat and in a front rest. I place a level up against the bottom of the stock, on top of the scope cap ....on and on to make sure rifle is recoiling level.
 
Posts: 961 | Location: Mint Hill NC | Registered: November 26, 2016Reply With QuoteReport This Post
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Thanks for the explanation.
 
Posts: 43679 | Location: 10,150 Feet Above Sea Level in Colorado | Registered: April 04, 2002Reply With QuoteReport This Post
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quote:
Originally posted by bendable:
Precise for a .243 win and for precise for .30-06 might be two different descriptions.

Both can be very accurate. It takes a good barrel, proper chambering, quality components, a good action, and a talented shooter.

Both cartridges are at a disadvantage to more modern cartridges for long distance shooting due to their case design. When these older cartridges were introduced, bullets were lighter and shorter. The current trend towards heavier and longer bullets provide better performance at long distances. However, with some hand load tinkering the 243 and 30-06 do OK with long & heavy bullets. Handloaders can do this, but it's more challenging for manufacturers of factory ammo.

A number of years ago -- before the popularity of 6BR-based chamberings -- George Gardner of GA Precision shot some steel matches well with 243 Win. 30-06 did well in NRA competitions (I think), before the 308 Win edged it out.
 
Posts: 6837 | Location: Colorado | Registered: January 26, 2008Reply With QuoteReport This Post
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quote:
Originally posted by sigfreund:
“I went out to my local shooting range and zeroed the rifle at 400 yards when ScopLevel #1 read level. I shot several groups to be sure of the zero. Next, I rotated the rifle until ScopLevel #2 read level. This produced a cant of 5°. I shot several groups at 400 yards with the canted rifle, and measured the effects each time.

“The results? Surprising, to say the least. When canted, the bullets struck about 4 inches to one side. I expected some horizontal movement. But I did not expect the vertical movement to be as large as it was — the vertical impact averaged 3.75 inches low!”

I realize that's what the website states, but I cannot believe the POI was a whopping 3.75" low, with a horizontal error of 4" for a 5 degree cant. IMO there were other factors which caused the drop error to be virtually the same as the horizontal error.

I've seen a number of issues with scope/rifle canting at various distances, with the most blatant being at the Nightforce ELR match at Q-Creek. Both 2 and 3 years ago, we had stage positioned on a notch which was high on a left-sloping ridge. The match director set 5 full-sized steel ram targets at 1200-1300 yards. The shooting position sloped slightly to the right, but the optical illusion of the ridge made us think the shooting position was flat. The ROs watched more than 100 shooters per day, with up to 10 shots per shooter. The vast majority of us had our rifles canted to the right, and it was really obvious when we observed those with bubble levels on their rifles. Stage time limits were tight, and we started from a standing position. We didn't have time to futz around and get comfy with the rifle position.

According to the RO, many of us missed our first shot on each target -- noticeably right and a touch low. If we followed our eyes and corrected for the POI, we often impacted with shot #2. Those who assumed their elevation dope was still good for the second shot, often impacted just below the rams on shot #2.
 
Posts: 6837 | Location: Colorado | Registered: January 26, 2008Reply With QuoteReport This Post
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I am glad to folks are taking the time to share .





Safety, Situational Awareness and proficiency.



Neck Ties, Hats and ammo brass, Never ,ever touch'em w/o asking first
 
Posts: 51677 | Location: Henry County , Il | Registered: February 10, 2004Reply With QuoteReport This Post
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quote:
Originally posted by fritz:
quote:
Originally posted by bendable:
Precise for a .243 win and for precise for .30-06 might be two different descriptions.

Both can be very accurate. It takes a good barrel, proper chambering, quality components, a good action, and a talented shooter.

Both cartridges are at a disadvantage to more modern cartridges for long distance shooting due to their case design. When these older cartridges were introduced, bullets were lighter and shorter. The current trend towards heavier and longer bullets provide better performance at long distances. However, with some hand load tinkering the 243 and 30-06 do OK with long & heavy bullets. Handloaders can do this, but it's more challenging for manufacturers of factory ammo.

A number of years ago -- before the popularity of 6BR-based chamberings -- George Gardner of GA Precision shot some steel matches well with 243 Win. 30-06 did well in NRA competitions (I think), before the 308 Win edged it out.


The .308 did more than just "edge out" the venerable 30-06, it caused the NRA and DCM/CMP to reissue new targets.

I'm going on my memory over a period of 40 years of competition shooting, so I can be a little hazy on specific dates. When I first started shooting Fullbore and Palma in 1981, the long range target was 12 feet wide and needed two people to operate. The .308 was getting into wide use and the 30-06 was fast disappearing from the circuit. During that decade, the scores increased so much the NRA (and the DCM/CMP) issued new targets, the current ones that are 6 feet wide at 800-1000 yards. Now, whether this was due to the switch from 30-06 to .308 or that the newer/better rifles were generally only offered in .308 and not 30-06, is still somewhat of a bone of contention, but that was long ago. The .308 in the form of the M1A/M-14 was completely overtaken by the AR-15/M16 in .223/5.56 in Service Rifle competition in the mid to late 1990s when the US Army Marksmanship Unit brought M-16 with their V8 loads to Camp Perry and proceeded to kick butt. Within a few years, virtually everyone was shooting an AR15/M16 at Camp Perry and other Service Rifle matches. I think the USMC kept their M14 at Camp Perry the longest and yet still let them go within a few years.

When I was last there in '05, I think it was, everyone had an EBR of various colors. My NM AR-15 is green.

This message has been edited. Last edited by: NikonUser,
 
Posts: 3216 | Location: Texas | Registered: June 20, 2012Reply With QuoteReport This Post
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A quick update with a real life event. Today, I shot in the monthly 1000 yard match. The winds were very calm for the first match or so, but that changed, of course.
So during the first match, I had finished my string and I was walking the line, doing "MD" duties. I was watching a friend shoot and looking at the target on my Samsung Note 8. I noticed that he was doing well, shooting Xs and 10s and all of a sudden, he got a 6 out the right and a little low. He looked at his rifle and he noticed that it had canted to the right and he really was a bubble off. You could actually see the cant as it was a couple of degrees. Somehow the friction brake on his (not that fancy) bipod had slipped and he did not notice it. Well, he did after the score came up.

Funny thing is, he has a bubble level on this scope, but it's a small one and he did not notice the slippage. That's one of the reasons I really like the level on my rifle, you can't miss it.

I did not have the heart to tell him that we just had that discussion on a forum. Don't tell him.
 
Posts: 3216 | Location: Texas | Registered: June 20, 2012Reply With QuoteReport This Post
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Thanks, NikonUser; these are the useful reports.
 
Posts: 43679 | Location: 10,150 Feet Above Sea Level in Colorado | Registered: April 04, 2002Reply With QuoteReport This Post
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Am I to understand that the majority of of shooters that choose to utilize levels with scoped rifles are most often shooting from a stabilized support ?

Either bags or bi pods.

And not off hand or sitting or prone positions .





Safety, Situational Awareness and proficiency.



Neck Ties, Hats and ammo brass, Never ,ever touch'em w/o asking first
 
Posts: 51677 | Location: Henry County , Il | Registered: February 10, 2004Reply With QuoteReport This Post
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It has been a very long time since I shot much from the traditional unsupported positions (offhand, kneeling, sitting, prone), but my prone and sitting positions at least were solid enough that I might have checked a level if my rifle had had one in those days. Today some of the positions with one type of artificial support or another (table, 55 gallon drum, etc.) that are not absolutely solid are still firm enough that I check my position with the level if I have the time and the gun is so equipped.

Of course, at the shorter ranges where I might shoot with less artificial support the actual need to check the level is much less.
 
Posts: 43679 | Location: 10,150 Feet Above Sea Level in Colorado | Registered: April 04, 2002Reply With QuoteReport This Post
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quote:
Originally posted by bendable:
Am I to understand that the majority of of shooters that choose to utilize levels with scoped rifles are most often shooting from a stabilized support ?

Either bags or bi pods.

And not off hand or sitting or prone positions .


I don't know a majority of shooters, so make of that what you will. I have never seen hunting rifles or target rifles (used at shooting ranges), with a bubble level. But then again, as I said, I don't know a majority of shooters.

The vast majority of shooters never go much beyond a 100 yards, the distance of most local ranges. Many consider 200 yards to be long range. Granted, there has been a trend for some shooters to go for longer distances like 300 yards, but in the grand scheme of things the longer the distance, the less shooters there are slinging jacketed lead at those distances.

The effects of a canted rifle only come into play at longer distances and for those who require a certain degree of precision.

I have seen levels on match rifles with peep sights for the long range. I have seen levels on match rifles (any/any) used from prone with a sling. I see them on ALL F-class rifles, F-TR or F-Open, and I know some benchresters use them as well. I know that PRS shooters have them on their rifles, but I have no idea of the degree of iniquitousness of levels on the PRS rifles. Is it de rigueur, like in F-class? I don't know, but I would think it would be, especially at the higher echelons, but I am happy to be corrected.

It's not a "elite" thing, it's just a matter of need and use. AT the distances where a level becomes a necessity for utmost accuracy,
nobody shoots unsupported; they will either sling it, bipod it, rest it or similar and at that point a level makes sense, otherwise it's a distraction.
 
Posts: 3216 | Location: Texas | Registered: June 20, 2012Reply With QuoteReport This Post
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