Velocity Press:  The Web Journal of Trenchant Opinion   An examination of controversial subjects based on facts, logic, uncommon sense and the inclusion of exculpatory evidence.


Air Rifle Ballistics

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RWS Model 54 recoil-less spring-piston magnum test

After years of successful hunting with the .22-cal side-lever RWS Model 48, I finally decided to try its recoil-free variation
—the Model 54. I had resisted because the M-54 anti-recoil mechanism seemed like a needless complication.
One of the most notable qualities of RWS air rifles is their legendary reliability; why complicate that, I wondered, with a gimmick?

 

Boy, was I wrong!! The instant after the first shot I discovered an amazing fact: my sight-picture of the target remained rock-solid throughout the shot!
With my M-48, the sight picture would always jerk off the target or even momentarily black out due to recoil motion. Maintaining a steady sight picture
had two immediate beneficial effects. 

  • First, it let me see where I had hit (or missed) my target. With the M-48 (and all other magnum powered spring-piston air rifles) the recoil causes
    the rifle to move enough to knock ones view off—and even sometimes to result in image black-out. (And what a surprise at that first shot to keep
    seeing a rock-steady target!)

  • And second, by being able to view the target uninterruptedly, I was able to notice my post-shot barrel motion. I discovered I was sometimes waving
    the barrel right after the shot; was I also waving it during the shot? I was—thus answering the question of why, sometimes, I just couldn’t get on target.
    This is such a useful effect, it seems to me that practice with a Model 54 might do a lot to cure wandering magnum marksmanship!

  • Air gunners who use PCP (pre-charged pneumatic) rifles are used to this advantage. The mass of the compressed air that squirts out their pellet is
    too low to cause much of an “equal reaction” (recoil). The mass of the piston and spring of a springer are enough to cause a significant recoil.
    Because the exit pupil of a telescopic sight (the shaft of image light coming out of the scope) is quite small—usually only about 5 mm—it doesn’t take
    much movement to misalign the exit pupil with your eye pupil (itself 2-6mm in diameter), resulting in loss of the sight picture. 

    But PCP rifles require a lot of supporting equipment—a scuba tank of compressed air, fittings, tubes, etc. And leaks are a problem. The big advantage
    of spring piston rifles is they sit quietly in the back of the closet. When you are ready to shoot, you pull then out, cock them—and shoot. Nothing could be simpler. 

    The Model 54 is one big gun. You really must have a sling to carry it around. A big gun deserves a big scope, and I used the RWS 4-12X 50 telescopic
    sight with one- piece rings. The ring has two anti-creep pins—a real necessity for all springers . The wider 50mm aperture
    gives a larger exit pupil meaning it is easier to get a sight-picture when you bring the gun to the ready, e.g., 6.5mm at 8X magnification—30% greater
    than 5mm at 8X for a 40mmm aperture scope.  The extra amount of light the larger aperture receives is not enough to make any practical difference.

    And it’s a powerful magnum. I measured 22 ft-lbs out of the box using RWS Superdome pellets. This results in delivering a whopping 8 ft-lbs to
    the target at 50 yards.  Eight ft-lbs is more than enough to humanely take most small game--crows, rabbits, woodchucks, squirrels, etc., with well-placed shots.

    Sighting in at 50-yards keeps the pellet within the “natural” zero range (within ±2-inch rise/drop).  Maximum effective range is 57-yards.  The trajectory
    and energy of the SuperDome (pink squares) and the Super H Point hollow point pellets are virtually identical—take you pick. Although as an air rifle
    hunter, I naturally trend toward round-head pellets because of their generally superior ballistics. However, the Super H Point (a modest hollow-point)
    gave me astonishing accuracy (see below).

     

    The RWS 4-12 X 50 scope has military (marked) stadia, giving the illuminated crosshairs reference points for how much to aim lower or
    higher at distances different than your zero range, and an illuminated reticule. I wasn't wild about this scope, packed with so many features
    except good optical performance.

    Many air gunners focus on air rifle velocity, believing this to be a measure of air rifle power; it is not. Velocity is proportional to energy and
    inversely
    proportional to pellet mass. The heavier the pellet, the lower the velocity from the same rifle. Here is the velocity graph of the .22-cal.
    Superdome pellet—846  fps at the muzzle, coasting to 500 fps at 50 yards.

    Because of the "velocity race," manufacturers usually use the lightest pellet in order to achieve the highest muzzle velocity. And it is true that
    light pellets usually post impressive muzzle velocities, but they shed energy and velocity rapidly. Some rifles (particularly in .177-cal.) may obtain
    higher energy from a heavier pellet than a lighter one. A heavier pellet (like the Superdome) will lose energy and velocity more slowly. By 25-yards
    they will generally exceed their lighter brethren in both factors. And heavier pellets almost always have superior ballistic coefficients, thus being
    less affected by crosswind.

    Shown below are the velocities of three pellets of different weights fired out of the same gun. Note how the fastest pellet out of the blocks is the
    lightest one. But by 30 yards it is already the slowest pellet! At 50 yards, the pellet with the slowest muzzle velocity has held on to it and is now the
    fastest at that range. Energy at range follows a similar pattern except that in many rifles, the heaviest pellet often produces the most energy at all
    ranges—and loses it the least quickly as well. That is why air rifle hunters tend to select pellets beginning with the heaviest one available,
    and then backing off of weight to find the compromise that gives the best combination of sight-in (±2-inch) range and downrange energy.

    Cocking the side-lever of the M-54 requires a hefty pull. As with all magnum-powered springers (and particularly with air-spring rifles)
    you should be sure you have the strength to manage the cocking effort. (A little practice goes a long way to making it easier.)
    Towards the end of the cocking stroke, one can feel the anti-recoil mechanism being engaged. The safety sits at the base of
    the receiver, handy to the thumb. It is resettable without re-cocking.

    The trigger set point is adjustable, and I backed-off the factory setting just a tad so that the M-54 fired when I thought it right to do so; not
    when I jerked the trigger to make it do so. 

    The discharge sound is solid grunt -–“kruck”-- rather than a bark. Missing a woodchuck one a windy day, I saw for the first time by the dirt
    the pellet kicked up how much Kentucky windage I had to apply for the next shot. A continuous sight-picture--what a boon to improving my
    yield of hits to misses! 

    Perhaps the biggest pleasant surprise was the field accuracy I was able to obtain after some practice with the Model 54. Its weight certainly
    reduces jitter, so I shot in the difficult offhand stance. The first five-shot pattern would barely fit inside a dinner plate! Darn! I muttered to myself,
    I know I can do better. So I screwed up my concentration--and shot a 1 X 2-inch pattern! That’s the best I’ve ever shot, offhand at that range--
    and amply demonstrates that with a gun that is inherently accurate, marksmanship is largely a matter of concentration on the task..

    Shooting the Model 54 has completely changed my mind about its anti-recoil feature. It is not a gimmick;
    it’s a splendid improvement that lets the varmint hunter really improve his shooting—and right away. He also
    immediately
    gets a much better chance of “bringing home the bacon,” instead of bringing home stories about
    “the one that got away.”

     

    How to choose Air Rifle Caliber

    © 2002, 2003 by Tom Holzel, with Jim Baumann

    With premium air rifles costing as much as they do, figuring out what particular brand and model to buy can be
    quite confusing.  On what do you base your choice? The first step is clearly deciding how much money you can
    afford to spend. This will determine the quality level, and the features of the gun.  After deciding this, the next most
    important factor is to chooser the correct caliber for the gun's intended purpose.  If you are going to own only one gun,
    this can be an agonizing choice.  Here's the approach I used to decide between a 5mm and .22-caliber Theoben
    Eliminator rifle for hunting in southern England.

    As a long time air rifle crow hunter in the U.S., I recognized that to English farmers, hares, not crows, are more of a
    nuisance, so they would be the varmint of choice in my new home in Oxfordshire.  With crows, long range is more important
    than high power, so for that task the longer reach of the 5mm would be the obvious choice. Would that caliber also be the
    optimum for fur bearers? When I examined the published performance I was puzzled by the ballistic data given the Eliminator
    on the Theoben website (http://www.theoben.co.uk/).  Their highly regarded 5mm rifle is listed as having a muzzle velocity of 880 fps,
    with 840 fps remaining at 50 yards. Energy figures are quoted as being 24.5 ft/lbs at the muzzle and 22.4 ft/lbs at 50 yards. 
    These figures indicate the Crosman Premier pellet used loses only 4.5% of its velocity over 50 yards -- yet drops by 23% the
    next 50 yards.  The .22-caliber figures were equally confusing.

    There are two ways to determine the trajectory of a pellet: Empirically on the range -- this is the most reliable method--or theoretically
    (and much more rapidly) by means of a ballistics software program.  To help me clear up the issue,  I bought an air rifle ballistic
    program developed by Jim Baumann of Lame Rabbit Software (Note: Jim is apparently no longer in business).  Let's see how the two
    calibers fare (at least on paper).

    To use ballistic software, one needs to know (or find out) the correct ballistic coefficient (BC) of the pellet being tested and therein
    lies the rub. The BC of a pellet is an extremely complex function that changes depending on a pellet's  range and velocity.   
    A pellet can have an excellent BC at one muzzle velocity and at one optimum range--and then flop miserably as the velocity is
    changed, or the measuring range altered. In the case of the superb 5mm Crosman Premier recommended by Theoben,
    Jim Baumann has measured its BC as is high as 0.040 at 25 yards, but more commonly at 0.0308 at 50 yards.  The big
    advantages of the 5mm Premier pellet are that of high, repeatable quality and that it has a high BC.  But -- unlike many other
    pellets--it maintains its BC to well over 900 fps. We use 0.0300 at 950 fps for the maximum usable power of this pellet. 

     

    To complicate matters even more, BC varies from shot-to-shot!  Below is a sample of a series of shots measuring BC of a
    5mm Crow Magnum (Eliminator) with chronometers set at 10 ft and 45 yards from the muzzle. 

     

     

     

     

     

     

     

     

     

     

    To determine maximum usable range, the shooter has to decide how many inches of rise above the telescopic line of sight is he willing
    to aim at intermediate distances. With 12-lbs-ft rifles this is usually 3-inches.  But with a FAC rifle this is usually 2-inches -- or less. 
    And the shooter must determine his own personal field marksmanship. Then, knowing the pellets BC, ballistic software lets
    us plot the trajectory for different sight-in ("zero") ranges.  

    Chart 3 shows the trajectories of the two calibers when sighted so as to result in a rise of  two inches, each at two different power settings. 
    The lower power settings are those which the Theoban website says result in the highest accuracy; the higher settings are those used by
    many American varmint hunters for maximum effectiveness. Recognize that with all mechanical devices, (your car, for example) extracting
    more power results in more rapid wear & tear.

    Notice (chart below)  that if we also allow two inches of drop, we can achieve an absolute maximum theoretical range (blue line) of the two calibers
    of 63 yards for the .22-caliber, and 72 yards for the 5mm. But, accuracy will probably hold up over the farthest reaches of our neat graphs only
    as wishful thinking.

    What this means is that while ballistic computer plots of air rifle rounds are useful as starting points, complex second-order aerodynamic
    factors begin to dominate at the higher ranges and velocities -- that is, much beyond 60 yards. Also, wind deflection alone can double group
    size from 50 to 70 yards.

    But wait -- can I even hit the 3-inch "kill zone" of my target out to 70 yards?  Certainly not from a standing position. However, when shooting hares,
    I will almost certainly be either sitting, or probably even lying down. But even using a bipod, will any air rifle shoot that accurately out to 75 yards?  
    In the field I can realistically put three out of four shots inside a 2-inch circle from the seated position at 50 yards.  If the pellets' flight continued
    perfectly, that would result in a 3-inch circle at 70 yards.  But perfection never happens.

        Robert Beeman, (founder of Beeman Precision Air Rifles in California) believes that down-range pellet instability is primarily caused by two factors:
    First, any random tipping of the pellet as its skirt loses final contact with the edge of the muzzle; and second, the imperfect distribution of the pellet's
    mass about its spinning axis.  In both cases the pellet can begin to wobble more -- and then less -- and then more again -- during its flight.
    This wobble becomes more acute the faster and the further the pellet travels.  Combine this with the minute shot-to-shot variations of power and it
    becomes easy to see why even with the best high-powered, long range air rifles, perfection is unattainable.

    This brings us to the next consideration -- "terminal ballistics"--the effect of the pellet on the target.

    Chart 5 shows us that the energy the two rounds carry at two different power settings. The reason the 5mm loses energy slightly faster is that its
    ballistic coefficient (BC) is less -- 0.0300 vs. 0.0340 for the .22-cal..  This is almost always the case, that larger pellets have better BCs than
    smaller ones.  In the case of the Premier, Jim Baumann believes the cause has to do with a pellet's length which has been optimized for long range.

    What is interesting about this chart is that, although the 5mm Premier pellet leaves the muzzle with more energy than the .22-cal H&N Barracuda,
    because the Barracuda has a slightly better BC, loses energy less rapidly. But think on this: By increasing power above the Theoben optimum,
    how much range and extra energy are we really gaining?

    Yet it is not energy but "lethality" that we seek. What is the difference?  Firstly, let us go to the sight-in range of 60 yards.  Of course the 5mm
    round is traveling a lot faster than the heavier .22. And the equation for energy is well-known: E= mv2/2. In other words, increasing the velocity
    just a bit results in a whopping increase in energy. But there's a major snag. 

    In my experiments shooting into an animal flesh simulator (Ivory soap), I discovered that a .177-cal Hobby pellet penetrates 7.5 to 8-inches
    when carrying 15 lbs-ft of energy. A .22-cal Hobby pellet only penetrates 5 to 6 inches with the same energy. The reason for that should be clear.
    The .22-cal pellet must clear out a wider wound channel per inch of penetration. Indeed, with these experimentally derived figures, the .22-cal
    creates a  short, fat wound channel with a volume of 0.19 cubic inches, while the.177-cal pellet creates a long skinny wound channel of 0.185
    cubic inches -- in other words the same wound channel volume -- an amazingly close experimental confirmation (and a great advantage of
    using Ivory soap for these tests).

    Now here's the high-velocity catch: Shooting both of these pellets into a critter with a diameter of only 2.5-inches means both pellets will exit
    the animal -- and carry with them unspent energy. But the .22 will have dropped off  half its energy in this example.   Since it can penetrate
    5 inches, and exits after half that distance, so it has used up half its energy or 7.5 lbs-ft. The .177-cal pellet can penetrate three times as far,
    so it will exit with 2/3rds of its energy intact. It will have dropped off only 1/3 of its energy, or 5 lbs-ft. Thus the fatter .22-cal pellet will have delivered
    50% more energy to the target; energy that is, of course, more destructive, or more "lethal." (Of course, these depths are theoretical in that they
    apply to Ivory soap which may or may not be an accurate flesh simulator.  If the pellet hits bone, a lot more of its energy is transferred to the animal
    -- in most cases, all of it.)  But there's more to the energy story.

    This over-penetration gave me the idea for a real hollowpoint pellet -- an egg cup design that would really open up.  The result was Dr. Beeman's 
    Crow Magnum hollowpoint pellet.  It will double in caliber inside a varmint and almost never exits the critter.  However the 5mm Crow Magnum
    hollowpoint BC is only 0.0263 at 900 fps. So you will have to experiment to see if the higher lethality of the Crow Magnum pellet is worth its
    slightly lower efficiency.

    Jim Taylor, a world famous big game hunter, wrote in the November 1947 issue of American Rifleman that his experience with the
    E=mv2/2 high-velocity equation did not comport with his extensive personal experience -- so he made up his own lethality index --
    the Taylor Index.  His equation is:

    TI = (grains*velocity*caliber)/7000.

    Note that velocity is really given short shrift in this equation; it is no longer squared. Because Taylor was using really big guns,
    his numbers come out big -- or, put the other way round -- when we plug in air rifle values, they come out very small. So I modified the
    Taylor Index and call it the Taylor Value. Instead of dividing by 7000, I divide by seven.

    Using that modification, we can calculate the Taylor Value for the Eliminator 5mm and the .22-cal pellets at 60 yards. They are:

    TV5mm60 = (14.3grs * 729fps * .20-in)/7 = 292

    TV22cal60 = (21grs * 601fps * .22-in)7= 422

    Wow -- the .22-cal comes out  44% more lethal at 60 yards than the 5mm.  Now we can see where the .22-caliber's fur-punching
    reputation comes from!

    So here's the question I have to answer for myself:

       5mm   .22-cal   Delta  
    Max Range (yds):     63 57 22% in favor of 5mm 
    Taylor: 292 422 44% in favor of .22-cal
    Pellet Pressure* 541 473 14% in favor of 5mm

    What is more important -- 22% more range or 44% more lethality?  [New commentary] Or a 14% higher "Pellet Pressure"? *(Pellet Pressure is
    the energy at the target divided by the cross-sectional area of the pellet. For example, 300PP is required to punch through the folded wing
    feathers of a crow.) Notice that the 5mm pellet has a better PP (penetration) than the .22. This is one reason why in America, the 5mm pumped
    up to achieve 950 fps with the Crosman Premier pellet has developed such a very strong following among varmint hunters.  It results in a high
    sustainable accuracy at the greatest ranges, with sufficient lethality to do the job. Future experimentation will reveal which of the two pellets
    create a larger wound channel.  It will be very interesting to compare the wound channel volume of the Premier vs the Crow Magnum pellets
    as well. (After all that work to determine efficacy, it still remains a matter of opinion and personal choice!) 

    Chrony ballistic software

    Before you compute pellet trajectories, you have to measure the velocity at two distances--typically zero and 35 or 40 yards. Shoot five pellets
    through the Chronograph at zero yards distance, then five pellets through it at 35 or 40 yards. Note that the Chrony does not require the white plastic sun
    shields unless the sun is out and brilliantly clear.  Even a hazy sun won't give good readings with the shields in place.  If you plan on
    doing a lot of testing, buy two Chronys and shoot through both of them at the correct distances, at the same time. Then average the velocities,
    throwing out any fliers.

    The Chrony ballistic software is a very awkward and buggy product that can be used only after much fiddling about.  But then it is extremely useful.
    Here is a short-cut that works just fine. You don't need a PDF converter to view this program, although it may sometimes be necessary to view
    certain documents and files.

    Struggle to get the toolbar header to appear.  Under "Project," click to the "Trajectory Table" at which the screen (below) will open--except there
    won't be any numbers in the fields.

    Fill in the variables in the screens marked "Range," "Sight-in," "Target" and "Bullet." In order to fill in anything, you have to first erase
    (not overwrite) anything in the blanks. 
    Then (and this is the secret to making this product work) estimate your pellet's ballistic coefficient,
    and enter it in the B.C. field.  

    You will also have entered a velocity value for either zero yards or 5 yards.  Where the chart says "Velocity, 717fps" was where I entered  the average
    velocity at that range of 5 to 10 pellets. You will also will have changed the "Range" distances to 100 yards in 5 yard increments.

    Now, each time you enter an estimate of BC, all the chart figures change (or hit "Compute" to make them change) (Except the zero yards figures).
    Then look at the "velocity (fps)" values for the other, more distant ranges you used to test your pellet with the Chrony chronograph--say the 45 yd value. 
     It will change with each new guess of BC. When the velocity of the table at 40 yards changes to the figure you obtained in the field--voilá--you will have 
    correctly guessed the pellet's BC.  Now the rest of the table's figures will also be correct--energy, velocity, drop, etc. for all distances. Now you can 
    copy the drop figures to Excel to make a trajectory chart.

    Since a pellet's BC varies with its velocity and range, you can see that BC is not anything intrinsic to a pellet, such as its mass.  Rather, BC is an
    abstract factor
    used to make trajectory calculations come out right!  The actual Chrony trajectory computation is quite accurate--within 1/2 inch
    as far as I could tell (and even that difference is just as likely to be mine and not that of the program). For a more detailed explanation of BC,
    check out this
    informative website.
    _____________________________________________________ 

    Tom Holzel is author of The Air Rifle Hunter's Guide, Velocity Press, (Sold by Beemans and Crow Busters).  He was hunting editor for
    American Air Gunner
    magazine and has written numerous air rifle reports including on the Theoben .22-cal Crow Magnum and a series of RWS air rifles.
    Has most recent article on air guns was with John Zent, Editor of the NRA magazine American Hunter, August 2002.

    Jim Bauman is a professional ballistician and veteran air rifle user.  He is the author of the "Lame Rabbit" air rifle software program
    used to produce the data and charts for this article.

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    For an outstanding treatise of various aspects of air rifle ballistics--particularly internal ballistics--see this excellent
     site: http://www.arld1.com/

    For a tremendous trove of airgun knowledge, see Dr. Beeman's comprehensive web site:http://www.beemans.net/
    See in particular Dr. Beeman's article on Airgun ballistics at http://www.beemans.net/airgun%20ballistics.htm.

    For a catalog of ballistic source material, see: http://www.goneshooting.co.uk/Ballistics.htm

    A neat air rifle website is the British air rifle Review Centre

    For more air gun hunting, see:  http://www.airgunhunters.com/index.html

    Finally, another extensive listing of air gun material: http://www.airgun1.com/listings/adult_precision_air_guns.html

    *************************************************************

    Scope Recoil Creep

    One of the most pernicious problems of magnum powered spring-piston air rifles is the effect their towel-snapping recoil has on the
    mounting of the telescopic sight.  Here is a photo of my trusty RWS .22-cal Model 48 showing the channel the scope stop screw
    carved into the scope rail.

     

    Admittedly, this mounting has held up for about 4 years of shooting.  But when it went, it went quickly.  Suddenly I was missing
    40-50 yard woodchuck shots that I had routinely hit before.  The simplest repair in this case would be to unscrew the rail and
    reverse it. (Be sure to drill a lubrication hole.)  But I bought a new rail from RWS ($39.95) However, the screws have been racked
    in so tightly, I will probably have to have them drilled out.  My Kodiak scope mount is also starting to show some wear (Photo below).

    Needless to say, all screws should be set with full-strength (blue bottle) thread lock liquid ("Lok-Tite"). Be sure to clean the
    threads with alcohol first (Use vodka or gin if you don't have denatured alcohol.) One essential point: Do not try to save weight by
    buying scope mounting parts whose screws or screw threads are made of anything but steel.
      I have not found any scope
    mounts which use alloy screw threads--male or female--that will hold up; they must be steel. (but the hardware that holds the scope
    tube can be aluminum.) Also, one-piece scope mounts seem better suited for the recoil shenanigans of spring piston air rifles.

    The scope tube can slide perniciously, too. Wrap a piece of "Scotch" (cellophane) tape around the top of the scope tube right next to
    the scope ring.  Check the edge of the tape frequently to see if the scope has moved--especially if you notice your marksmanship is
    slowly deteriorating. If you can't get the scope tube to stop slipping, insert a very slender strip of Emory cloth between scope and ring.
    The bite of the Emory cloth grit will hold the scope fast.

    A third source of creeping inaccuracy is the receiver of the rifle coming loose from the stock. It should not, of course--rattle the
    tiniest bit if you jiggle it. One sign of a loose receiver is a tight group marred by 2-3 flyers (instead of just one.)                                                                                                                                     

                                                                                                                              

        

     

     

     

     

     

     

     

     

     

     

     

        Here is the recoil dent worn into the Kodiak scope mount. (Red arrow).

     

     http://www.airgunsofarizona.com/beemanscopes.html

    http://www.sportsmatch-uk.com/products.html

    http://www.reliablehost.com/bsquare/airgun_1.html
         http://www.theoben.co.uk/frameset.html

    ************************************************************

    Expanding Air Rifle Pellet

    So-called hollowpoint pellets have been around for along time--but none of them expanded at all inside target critters. None, that is,
    until the Beeman Crow Magnum hollow head pellet.  Here is a photo of a .22 Crow Magnum taken out of a red squirrel shot at 37 yds
    with a 21- ft-lbs RWS Model 48.  The pellet entered the squirrel above his front leg and was recovered pressed up against the inside of 
    the hide of his rump. (In other words, the pellet had traversed most of his length.)  As the photo shows, even at that range, the pellet did
    expand to increase the diameter of the wound channel.

    Crow Magnum

     

     

     

     

     

     

     

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    Send checks to Velocity Press, 3 Durham St. Boston, MA 02115. First Come, First Served. Email to ascertain remaining
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    known airgun every produced is a labor of love by Dr. Robert Beeman and John B. Allen. It's 568 pages of listings, photos, factoids
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    Airgun Information International
    PO Box 516
    Healdsburg, California 95448-0516
    USA

    _______________________________________________________________________________________________________

    Ballistics of 3 RWS Pellets

    Comparison of .22-Caliber HyperMax, SuperPoint Extra & SuperDome air gun pellets

    Rev 18 Sept 10

    The RWS HyperMax is a lightweight (9.9 grain) pointed pellet that looks identical to the 14.5 grain SuperPoint. It is advertised as offering 25%
    more velocity, a selling factor that must be examined closely to see if that is really what you want. I compared those two pellets to my favorite
     RWS hunting pellet, the 14.5 grain SuperDome.

    [Insert Photo]

    Let’s look first at the advertising claim of the HyperMax velocity advantage:

    The muzzle velocity of the HyperMax pellet is 22% higher than that of its heavier twin in this air rifle with 16 lbs-ft of energy.
    But notice that by 35 yards its speed is equal to the SuperPoint, and drops faster thereafter. The SuperPoint starts the slowest (690 fps)
    and at around 30 yards overtakes the others in velocity. But the difference between the two heavier pellets is very slight and could easily
    exchange rank in different air guns.

    For hunters, pellet energy at the target is a much more important factor than speed (except that higher velocity does mean a
    flatter trajectory). Here is the energy comparison.

    Note the SuperPoint pellet starts out with the least energy—15 lbs-ft--and loses it to air resistance the least quickly. At 40 yards it begins
    to edge ahead of the SuperDome. But again, the difference between the heavy pellets is slight. The HyperMax energy at 40 yards is 6 lbs-ft
    vs 9 lbs-ft for the SuperPoint. 22% greater velocity, but 50% less energy is the HyperMax trade-off when used for hunting.
    (Note: The graph symbols do not fall smoothly on the curves due to rounding errors of the ballistics program)

    But, the HyperMax energy situation is reversed in less powerful air guns, see LP8 results below.

    Here is a comparison of the trajectories of the three pellets. The vertical scale has been highly exaggerated to show the differences
    more clearly. Note that while the SuperPoint and the HyperMax both strike the bull’s eye at 50 yards from the same gun, the
    HyperMax trajectory rises to only 2.4 inches at 30 yards while the SuperPoint climbs to 2.6 inches. The SuperDome crosses
    the line of sight at 47 yards. This is because its Ballistic Coefficient (BC) is worse—0.015 vs 0.018 for the SuperPoint.
    The SuperPoints also hit the 50 yd target 2 inches higher than the other two pellets using the same zero setting.

    The lightweight Hypermax has a BC in this gun of 0.010. Ballistic Coefficient is a measure of the efficiency of the projectile
    (pellet) traveling through the air. Heavier pellets generally have a better (higher) BC and are less effected by cross wind.
    On a windy day not well suited for hunting accuracy, the HyperMax would be off by as much as a foot while the other pellets
    were off by a few inches.

    The trajectory plots show the main HyperMax advantage—a flatter trajectory at short to medium range. Its greatest advantage
    will be at shorter ranges in less powerful air guns and in still weather. It is an excellent pellet for air pistols target competition,
    and possibly for short range pest bird control.

    Here in a nutshell is the trade-off of weight vs velocity. These are graphs comparing the .177-caliber HyperMax and the
    SuperPoint Extra pellets shot out of the RWS LP8 pistol:

     

    It is easy to see the higher velocity of the HyperMax—32% in this case. But here is a really surprising effect. The HyperMax also
    has the most energy in this low-power situation! The LP8 pistol just can’t get the heavier SuperPoint pellet going. With the longer
    barrel of a magnum air rifle, this situation is reversed  with the lighter pellet already out the barrel before it has extracted all the
    energy of the propelling column of air. 

     

    The much flatter trajectory of the HyperMax (Blue line, compared here against it lookalike stable mate, yellow line, the SuperPoint Extra)
    makes it the clear pellet of choice for indoor short-range target shooting.

    One major irk for me was the platter in which the HyperMax pellets are sold. It was impossible for me to set this artistic marvel down
    outdoors without spilling pellets (But it probably works fine on a table or bench indoors). My advice: dump the pellets into a standard
    pellet tin and be done with it.

    No matter how delicately you set the HyperMax pellet tablet down, pellets leap out and escape to the ground.

    By these accounts, for hunting purposes the SuperPoint outperforms the SuperDome; it has the same down-range energy,
    it has a flatter trajectory. Yet I prefer the latter for most hunting. Why? Let’s take a closer look at the ballistic figures.

    SuperPoint

    SuperDome

    HyperMax

    14.5 gr

    Std Dev

    14.5 gr

    Std Dev

    9.9 gr

    Std Dev

    687.3

    12.52138171

    715.1

    3.707425

    853.1

    7.86117

    669.9

    4.4%

    717.3

    0.8%!!

    848.1

    2.5%

    696

    710.8

    832.2

    700.8

    715.3

    847.9

    698

    721

    844.9

    Average

    690.4

    715.9

    845.24

    Delta V

    -22%

    -18%

    Shown here are the velocities of five shots for each pellet at zero range. Note that I alternated pellets at every shot, shooting
    a different one after each shot to even out possible accumulating variations of rifle power. The five SuperPoint shots have
    a maximum velocity difference of 4.4%. The SuperDome an incredible tight 0.8% (which is pretty amazing). It’s roughly the
    difference between a two-inch group and a three-inch group at 50 yards. Thus for me in that air rifle, the SuperDomes are
    more accurate in the vertical direction. And I found that in fact the SuperDomes usually gave me a tighter group than the
    SuperPoints. Although the difference was not large, at 40-50 yards, being an inch off is often the difference between a hit and
    a miss. However (there’s ALWAYS an "however"), when hunting crows, I prefer the SuperPoints. Crows are nearly always shot
    from the side, perched in a tree. (Frontal shots are rare because they would inevitably see you.) Folded crow wings form a stiff,
    very effective catcher’s mitt, and I have shot crows out of trees with .25-caliber rounds, only to have them get up after a moment
    and fly away! The pointed pellet has a better ability to penetrate this feather trap and effect a clean kill rather than a momentary knock-out.

    What have we learned? From this comparison we see there is no such thing as a "best pellet." There are only a lot of
    variables in pellet characteristics. You, the shooter, has to decide which pellet characteristics are the most important
    for the task at hand
    —and then pick the pellet that best meets those needs. This can be learned by lots of trial and error;
    or it can be more quickly and accurately learned by getting a chronograph and testing your pellets yourself.

     

     


     

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