by B.B. Pelletier
This report is another response to a viewer of our Airgun Academy videos. In episode 22, we say the following at 3 minutes, 20 seconds into the video, “When using real hunting pellets, you have to realize that the velocity and, therefore, the power is going to be significantly less [than the light pellets the rifle is advertised to shoot fastest].” A viewer took issue with that statement, so today I’d like to explore how airguns handle pellets of different weights.
There are three different types of airgun powerplants: pneumatics that store air under pressure and release it with the shot. This compressed air pushes the pellet and gives it it’s power. The pneumatic powerplant pushes the greatest volume of compressed air behind the pellet and, depending on design considerations, is potentially the most powerful type of airgun powerplant.
Spring-piston airguns store no air. They have a spring-powered piston that releases with the shot and moves forward to compress a very small amount of air that gets behind the pellet to push it. The pressure of this compressed air is very high, but the volume is very small; once the pellet starts down the barrel, the air pressure behind it drops off fast. By the time the pellet leaves the barrel, there’s very little pressure in the air behind it — especially compared to a pneumatic airgun.
Guns that use carbon dioxide act more like pneumatic guns, except that carbon dioxide is under less pressure than compressed air; plus, it expands slower because its molecule is larger than the atoms contained in compressed air. CO2 guns act like pneumatics to a point, and then they’re limited by their use of the larger CO2 molecule, where compressed-air guns, which are pneumatics, have much higher limits.
How it works
How does this affect the performance of an airgun? Most commonly, when the pellet weight increases. The power of a spring-piston gun decreases, and, of course, the reverse is also true. It’s not an absolute physical law, but only a general relationship. There are some design considerations such as the contact surface of the pellet with the bore and the lubricity of the lead alloy that can change this relationship slightly. However, the relationship still stands.
British airgun magazines have been talking about this since the 1980s. It’s very important to them because of their legal 12 foot-pound power limit. If a new pellet can come on the market and increase the performance of certain airguns that are currently legal so they exceed the legal limit of 12 foot-pounds, then the entire airgun community needs to be aware of it! Once it becomes known that a certain pellet can do that, the authorities will be using that pellet to test all airguns. Let’s put this relationship to the test today and see if it holds any water.
Using a .22-caliber Diana 27 spring rifle, I’ll shoot three different weights of pellets. If the relationship holds true, the lightest-weight pellet should produce the greatest power, the medium-weight pellet should produce the second-greatest power and the heaviest-pellet should produce the lowest power.
RWS Hobby
The .22-caliber RWS Hobby pellet weighs 11.9 grains and averages 490 f.p.s. in the Diana 27. That means it produces an average 6.35 foot-pounds of muzzle energy.
Crosman Premier
The .22-caliber Crosman Premier pellet weighs 14.3-grains and averages 459 f.p.s. in the Diana 27. It produces an average 6.69 foot-pounds of energy at the muzzle.
Beeman Kodiak
The .22-caliber Beeman Kodiak pellet weighs 21 grains and averages 352 f.p.s. from the Diana 27. It produces an average 5.78 foot-pounds of energy at the muzzle. I am aware that the Pyramyd AIR website says the Kodiak weighs 21.14 grains; but the Kodiaks I’m using are several years old, and I’ve weighed them on an electronic scale at exactly 21 grains.
So, we already have an exception to the general rule, with the Premiers producing greater muzzle energy than the lighter Hobbys, where the relationship predicted the opposite. But the general trend does remain in force, as the much heavier Beeman Kodiaks produce significantly less muzzle energy than the lighter pellets.
Now let’s try these same three pellets in a tuned Beeman R1 and see what happens. If the relationship holds, we should see the lightest pellet making the greatest energy and the heaviest pellet the least, in a linear relationship.
RWS Hobby
The .22-caliber RWS Hobby pellet averages 817 f.p.s. in the R1. That means it produces an average 17.64 foot-pounds of muzzle energy.
Crosman Premier
The .22-caliber Crosman Premier pellet averages 750 f.p.s. in the R1. It produces an average 17.87 foot-pounds of energy at the muzzle.
Beeman Kodiak
The .22-caliber Beeman Kodiak pellet averages 575 f.p.s. from the R1. It produces an average 15.42 foot-pounds of energy at the muzzle.
Again, the Premier pellet stepped out of line by producing the greatest energy. But the Kodiak maintained the relationship.
What does this prove?
It doesn’t prove anything. It demonstrates a general relationship between pellet weight and power in a spring-piston airgun. You could test 10 more guns and get several more anomalies, including a gun that actually shot the heaviest pellet with the greatest power. In fact, I’ll tell you how to do that in a moment.
But if you tested 10 different spring-piston air rifles, you would probably still see the general relationship holding most of the time. I’ve been doing this for many years, and I’ve seen it happen too many times to doubt that the relationship does work as described.
How to beat the relationship
I learned, when testing several exotic tunes while writing the Beeman R1 book, that a heavy piston always favors the heavier pellet. So, simply adding sufficient weight to a piston will change everything. But it will also give you more piston bounce and poor performance with a broader range of middleweight and lightweight pellets — which is why the pistons of spring guns weigh what they do. They’re made to give the broadest possible range of performance within the expected power band of the rifle they were made for.
When I wrote the script for episode 22, I was thinking of spring-piston airguns when I wrote the line that the viewer took exception to. That’s because the huge preponderance of airgun hunters today use spring-piston rifles.
Before you jump down my throat for saying that, I do realize that there are thousands of hunters using PCPs; and in some warm spots, there are even hunters with CO2 guns. But that doesn’t change the fact that most airgun hunters in the U.S. still use spring-piston rifles today. I shouldn’t have made a broad statement like that in the video without qualifying it, and the viewer was right to voice his concern. We’ve added corrective text to the video at that point.
But this report isn’t really about that video. It’s about learning how pellet weight performs in an airgun. According to this logic, precharged guns develop more energy with heavier pellets and less with lighter pellets. So, let’s switch over to a precharged pneumatic rifle and run the same three pellets, to see what happens. If the relationship holds as it’s stated, the heaviest pellet should be the most powerful and the lightest the least powerful.
For this test, I used an AirForce Talon SS with an optional 24-inch .22-caliber barrel. The power was set to 10.
RWS Hobby
The .22-caliber RWS Hobby pellet averages 1035 f.p.s. in the SS. That means it produces an average 28.31 foot-pounds of muzzle energy.
Crosman Premier
The .22-caliber Crosman Premier pellet averages 982 f.p.s. in the SS. It produces an average 30.63 foot-pounds of energy at the muzzle.
Beeman Kodiak
The .22-caliber Beeman Kodiak pellet averages 882 f.p.s. from the SS. It produces an average 36.28 foot-pounds of energy at the muzzle.
So, this time, the relationship held exactly as predicted. You can expect the same relationship to play out in every pneumatic, regardless of the power level at which it performs.
So, what?
Okay, I’ve explained an old relationship between pellet weight and performance. What about it?
A couple of things, actually. First, with the modern uber-magnum spring rifles, you can expect to see a lot of reversals in the relationship. That’s because they have heavier powerplants that are designed for heavier pellets. So, things may not be as cut-and-dried as you see here.
Second, I want those of you with chronographs to do your own tests and report the findings. That way, we’ll see if the relationship still holds over a much wider sample of airguns and pellets than what I’ve shown. Just choose pellets with weights that are separated by a good margin, so each one stands apart from the others.
And, finally, this is a lesson you need to internalize, because it’s fundamental — or at least I hope that all of us can prove that it still is. In the same way that a longer barrel increases the velocity and power in a pneumatic, this relationship will help you as you move forward in your airgun journeys.
I am not surprised that the spring piston rifle bucked expectations to some degree, while the PCP performed just as conventional wisdom would dictate. The spring piston rifles seem to like neither a very light pellet nor a heavy one. Like Goldilocks, they seem to like the one that is just right.
I prefer the spring piston power plant due to the fact that it doesn’t need any other auxiliary devices to function, such as high pressure pumps, or tanks or CO2. The spring piston gun has a magical quality that can not be explained. Oh yes, PCPs are great, I love my Marauder, my Discovery and my CZ 200S. Despite their accuracy, they have a clinical quality to them that puts me off a little bit. Also they are not self-contained. Without a filling device they are useless. Meanwhile, BB is using a spring piston powered rifle that has not been manufactured in several decades for one of the guns in this test. That says a lot, does it not?
I must admit, I am not all that interested in power. Nearly all of my shooting is at targets, not live animals. However, I do need to shoot the odd squirrel who can’t take a hint. My fastest kill was from an HW57 in .22 cal. A spring powered powerplant that shoots .22 cal pellets rather slowly by most accounts. Poor thing was dead before it hit the ground. I have shot other squirrels with higher powered guns that one would guess would be critical injuries, only to make me follow them and put them out of their misery. It hurt me more than it hurt them.
This is to say, power isn’t everything, or anything. Accuracy, and shot placement is more meaningful. Enjoyability to shoot is most meaningful of all.
The squirrels won’t go anywhere but straight down DRT with head shots. With your equipment and skills, that type of shot would be no problem!
Mike
Head shots are best, if you can make them every time. I shoot center of mass with a .177 Gamo Big Cat, Gold Trigger, and humble Gamo 4×32 scope using Super Domes. It drops them every time. My concern that if I do not hit them in the brain, I’ll rip off a jaw or something, the ground squirrel will get away and linger a painful death.
Pete
Pete
I agree with you whole heartly on the chest shot. A slightly off head shot could be horible. Now on the subject of pellet power, my take is that for hunting the CPL or JSB Exact will usually have passed the lighter pellet by the time it has reached 20 yards. This is simply because of the higher BC of the heavier more aerodynamic pellet. And this should hold true for spring guns or pcp’s. I would like to try proving this but I don’t want to shoot another hole in my chrony.
Loren
Loren,
Thank you for the pellet tips. I have tried the Eunjin 1.6gr .177….talk about BC..they measure near 8mm long near 2 times the 4.5mm diameter. Took a few shots at a very heavy wall dog food can and a green DF 2×4…very impressive. I will try it out at 20~30 yards maximum to avoid a near rainbow trajectory. Air Guns will be a Hatsan Webley Tomahawk and a Gamo Big Cat 1200.
Thanks again,
Pete
Howdy Slinger, Ditto. Ya just nailed a bull. That’s why I see airgunnin’ as more of a lifestyle than a hobby. No matter how much ya know there’s always more ta learn. In my world It’s the difference between ridin’ a Harley & bein’ a biker. B.B., Ms. Edith & the gang, sharin’ what they’ve learned & continue ta learn is a great help & inspiration. Thanx, ya’ll. Ride/shoot safe, Beaz
Beazer
It is good to read that someone is taking up what I am putting down. I think we think alike.
On the subject of head shots vs. center mass shots are concerned, I have shot several squirrels at center mass with high powered air rifles. The pellet passed right through the chest cavity, but the little buggers are tough and can run off. I will track them down no matter what it takes to ensure they don’t die a horrible prolonged death, but I have seen a squirrel with 3 chest shots still running.
I don’t take shooting animals lightly because I simply won’t do it unless I have to. I shoot to kill, but the pellet doesn’t always hit its mark. Its called ‘hunting’ instead of ‘killing’ for a reason. The thing about squirrels is, they are very twitchy and move quickly. And they are very tough. If they would do me the favor of remaining still, I am confident I could hit them right next to the eye every time.
Mike, I do appreciate your vote of confidence in my skills. And I aim for the head, which is the best advice. Thanks.
An excellent blog, B.B. This is something I have been meaning to try ever since I got my chrono. The thing is , I got a whole raft of guns to choose from.Since I am very interested in what you have to say about a heavy piston and it’s associate problems, I think I will test my HW97 in .22cal. And an HW85 in, 177. I would assume the calibre has no real bearing on the outcome? I will start as soon as I buy a new 9 volt battery for my Beta. Thanks again for the blog. You are a big reason I have stayed with this sport. Well,You and Kevin, and Duskwight, and Slinging Lead, etc. etc.
Titus
Well….been there.
When it comes to springers, you have to test each pellet to see how it is going to work.
I have seen lighter pellets shooting slower than heavier pellets. No question about a difference in power there.
I have seen two different pellets in the light range shoot completely opposite in velocity (one expectedly high but the other unexpectedly low), and the one that was best had either more or less energy than a heavier pellet….depending on exactly which heavier pellet that it was compared too.
Then there is the other thing…
Energy at the muzzle compared to energy downrange. If you choose the right pellets to compare, the one that has the most energy at the muzzle will have less energy down range.
twotalon
Twotalon,
I totally agree. I’ve given up trying to apply logic. Having a chronograph has been an invaluable tool.
B.B.,
Very interesting blog today and pretty much mirrors what I have observed. A few examples:
.22 cal HW77
14.3gr Crosman Premier 652 fps 13.5 ft lbs
21.2gr Beeman Kodiak 513 fps 12.4 ft lbs
26.2gr Skenco Big Boy 456 fps 12.1 ft lbs
IZH 46M
5.0gr GTO Lead Free 500 fps 3.1 ft lbs
7.9gr Crosman Premier 440 fps 3.4 ft lbs
13.0 gr JSB Exact Monster 350 fps 3.6 ft lbs
16.1gr Eun Jin 320 fps 3.7 ft lbs
Benjamin Katana
12.0gr RWS Hobby 900 fps 21.6 ft lbs
14.3gr Crosman Premier 854 fps 23.4 ft lbs
21.0gr Beeman Kodiak 720 fps 24.2 ft lbs
Paul in Liberty County
Paul,
Thanks for sharing your data.
B.B.
B.B.,
Another great Blog. Forwarded it to all my air gun pals. Could you please post the energy formula ?
I should have written it down when I was watching one of the American Air Gun episodes.
Thank you very much ( got to get a Red Chrony..)
Pete in California
Here ya go, Pete! About halfway down the page. Along with a nice online calc.
/article/What_is_Muzzle_Energy_August_2003/5
/Dave
Pete,
The formula is as follows
Pellet weight in grains times velocity squared and the sum is divided by 450240.
B.B.
Thank you Dave and B.B. very much !
Pete
BB,
I wasn’t questioning your/PA formula at all. After all, I’ve enjoyed watching Crystal do that calculation many, many times on TV, so it’s got to be right. However, I was questioning the other site.
-Chuck
Unfortunately, once you leave the SI metric system — the constants in the equation start to, uhm, drift.
http://guns.wikia.com/wiki/Muzzle_energy
And neither of those constants match to either of the equations in play (my HP calculators have had a SOLVER equation obtained from somewhere decades ago that use 450400, rather than 450240). Using the quoted values above I obtain: 7000 * 32.1739 * 2 => 450434.6 (SI-based), 7000 * 32.163 *2 => 450282.0 (US convention)…
So… Since the constant is a divisor: 450200 overestimates relative to the 450282 (US) (~0.02%) above which overestimates relative to the 450400 (~0.03%) that has been in my calculator for years which is overestimating relative to the 450434.6 (~0.01%) value derived from SI units converted to english measure. (Or… the numbers I posted with my constant are about ~0.045% lower than would result from BBs constant).
Another excellent education, BB.
Remember the IZH-64M 1mm, 3mm, and 6mm 10m six shot group sizes I mentioned yesterday? Here are the associated FPE taken from that site:
RWS Hyper Velocity 5.2gr, 527 FPS, 4 FPE (3.21 FPE) 6mm group
RWS Diabolo Basic 7.0gr, 480 FPS, 3 FPE (3.58 FPE) 3mm group
JSB Diabolo Exact 8.4gr, 455 FPS, 4FPE (3.86 FPE) 1mm group
The above numbers are from the “other site”. The numbers in parentheses I generated using BB’s formula taken from the earlier link in this posting. I don’t know how the “other site” calculated their numbers but they sure don’t match the PA Energy Calculator numbers even if you tried to round off.
-Chuck
Oh, yeah…
I have only looked at the nerf pellets in .177 in three different rifles….two springers and a PCP. They produced less power (even though the velocity was higher) than the rifles favored pellets.
twotalon
Here’s some of my data, from two .177 magnum rifles ( springer break-barrels ):
Ruger AirHawk .17 Magnum
Pellet Wt Ft-Lbs E: Vel (fps)
Crsmn SSP: 3.6 6.0 868
Raptor 5.2 13.4 1079
Gamo Match 7.7 12.3 848
Bmn CrowMag 8.6 12.7 814
JSB Exact 8.7 13.7 842
H&N ‘Cuda 10.2 13.0 758
Ben Discvry 10.5 12.7 738
Remington Summit .17 Magnum
Crsmn SSP: 3.6 5.8 848
Raptor 5.2 13.5 1071
Gamo Match 7.7 13.8 898
Bmn CrowMag 8.6 13.3 835
JSB Exact 8.7 13.1 831
H&N ‘Cuda 10.2 13.8 781
Ben Discvry 10.5 13.0 750
Not much correlation to see: SKIRT FIT likely plays a large part in velocity, thus energy?? —Barr
The fit of the pellet to the bore is also a significant consideration, isn’t it? How much power would be ‘lost’ blowing out the skirt of a loose pellet, and how much would be wasted in friction with a pellet that fits a touch too tightly?
There’s so many variables that any question B.B. presents to us is an immensely complicated issue.
To be precise: CO2 consistent molecule size is larger than the average molecule size of plain air (after all — CO2 is a small component of air, along with O2, H2O, lots of nitrogen, traces of argon, radon, helium, neon, xenon, maybe some vapors of H2SO4. some O3…)
Well… My old spreadsheet gets called up again… I really need to route a tornado through my parent’s basement, in order to clean out a 10m range, and then re-chronograph with actual averages. Most all of this spreadsheet consists of single shot samples, so there is no indication of variance within a pellet brand/model.
Once again, columns are pellet maker, pellet model, weight, chronograph, computed energy (The NRA 1000 might be 5 shot averages — it was quiet enough in the apartment)
Gamo NRA 1000 Special .177
RWS Hobby 6.9 926.7 13.16
RWS Super-H-Point 7.4 926.1 14.09
RWS Superdome 7.7 852.2 12.42
RWS SuperPoint 7.7 894.2 13.67
RWS Meisterkugeln Rifle 8.3 850.6 13.33
Predator Polytip 9.2 723.4 10.69
Benjamin Discovery (RN-HP) 10.5 709.5 11.74
Eun Jin Domed 15.6 528.0 9.66
Spring-piston, .177 caliber; approximately a 13+ ft-lb gun using pellets in the 7-8gr range; dropping to 11ft-lb at the 9+gr range.
Benjamin Marauder .177 factory settings ~2450PSI
Crosman Premier Wadcutter 8.0 952.4 16.11
RWS Meisterkugeln Rifle 8.2 940.8 16.11
Predator Poly-Tip 9.3 907.0 16.91
Beeman Kodiak Copper 10.2 877.6 17.42
Benjamin Discovery 10.5 872.4 17.74
H&N Barracuda Match 10.7 876.2 18.15
Beeman Silver Arrow 11.6 831.7 17.77
Eun Jin Domed 15.9 743.2 19.49
PCP, .177 caliber; A fairly distinct climb from 8gr @ 16ft-lb to 16gr @ 19ft-lb
RWS Diana M54 .22 (single shot each)
RWS Meisterkugeln 14.0 810.8 20.43
RWS SuperPoint Extra 14.5 778.7 19.52
RWS Super-H-Point 14.5 787.9 19.99
Beeman Silver Sting 15.8 751.1 19.79
Predator Poly-Tip 17.2 725.8 20.12
Beeman Silver Arrow 17.6 704.3 19.38
AirArms Field Plus 18.2 688.1 19.13
JSB Exact Jumbo Heavy 18.2 701.7 19.90
H&N Crow Magnum 18.2 669.9 18.13
H&N Baracuda Match 21.1 618.7 17.93
Gamo TS-22 22.0 561.1 15.38
Eun Jin Round Nose 28.5 465.9 13.74
Spring-piston, .22 caliber: Essentially a 19.5 ft-lb gun with pellets ranging 14-18gr; rapidly dropping for pellets over 18gr
Condor High Power Tank dial 8-0 .22
RWS Super-H-Point 14.5 1143.3 42.08
JSB Exact Jumbo Heavy 18.2 1058.0 45.23
AirArms Field Plus 18.2 1068.0 46.09
H&N Crow Magnum 18.2 1076.0 46.78
H&N Baracuda Match 21.1 1010.0 47.79
Gamo TS-22 22.0 977.1 46.63
Eun Jin Round Nose 28.5 949.7 57.07
Eun Jin Pointed 32.4 939.5 63.50
Condor Micro-Meter Tank dial 8-0 .22
Beeman H&N Match 13.0 727.4 15.22
RWS Meisterkugeln 14.0 708.2 15.59
RWS SuperPoint 14.5 686.8 15.19
RWS Super-H-Point 14.5 702.2 15.87
Beeman Ramjet 16.0 680.0 16.43
Beeman Silver Ace 16.2 672.6 16.27
H&N Crow Magnum 18.2 635.6 16.33
H&N Barracuda Match 21.1 618.7 17.93
Eun Jin Domed 28.5 554.6 19.46
Eun Jin Pointed 32.4 511.0 18.78
PCP, .22 caliber, two different valves but same striker preload. High power shows significant climb between 14gr @ 42ft-lb to 32gr @ 63ft-lb; restricted valve shows narrower climb through 13gr @ 15ft-lb to 32gr @ 19ft-lb
Supplementary comment
From what I’ve seen, spring guns tend to be fairly consistent in energy until the pellet weight gets either extremely light (I’ve not tried any of those plastic or alloy pellets) or extremely heavy.
Spring guns tend to have diminishing returns as the pellet weight increases. If you figure in the cost of heavier pellets, the cost per ft-lb of energy may not be worth the expense when shooting springers.
Edith
Wulfraed,
Yes, the “molecular size” of a CO2 molecule is larger than the molecular size of a O2 or a N2 molecule. But the kinetic theory of gases predicts that the RMS velocity of gas molecules is a function of temperature and molecular weight. So the main reason is that the CO2 has a lower RMS at a given temperature is that the CO2 molecule weighs more than an O2 or N2 molecule.
Regards,
Herb
Thank you for this informative review! I getting back into air-gunning after over a decade of lapse. This was very informative as I bought a Benjamin Marauder in .22 cal. I love this air-rife!
Once again, Thank you for the time Mr. Pelletier.
Well, this is a surprise. I thought that energy was determined entirely by the airgun powerplant, and the pellet just expressed it differently. A heavier pellet would give you less velocity but would make up the muzzle energy with the extra mass. That doesn’t appear to be the case based on the numbers. I suspect that I’m thinking of an ideal laboratory case, and that God is in the details–too many to name….
Argh, am just returned from a trip and a severe illness. I have lost the desire to shoot which is close to life itself. Most disturbing. But I hope to be bouncing back soon. Meanwhile, I can highly recommend The Avengers as a most entertaining film. As the cartoon song said:
“When Captain America throws his mighty shieeeeeeld!
All THOSE who CHOSE to opPOSE his shield must FLEE!”
Matt61
I hope you get feeling better soon.
When I get sick, not being able to shoot always makes me feel worse.
Les
Matt61
I pray for your speedy recovery. Illness is insidious in its ability to rob us of the desire to do the things which make us most happy. I can’t imagine that there is another librarian in the country that is as passionate about shooting as you are.
Best wishes.
This question was sent to the wrong address, so I have posted it here,
Hello, Tom
I’ve been reading some of your stuff on airguns. I’m wondering if you
can refer me to a text or url that discusses the theory and relationship
of air gun functioning and tuning. I have two Marauders, .177 & .25.
Thank you, Doug
Doug,
Doug,
What you want is someplace where the Marauder is discussed, because no other PCP adjusts the way it does.
Let me suggest the Crosman Airgun Forum:
http://www.network54.com/Forum/275684/
B.B.
Hi, Doug. Another Marauder tuning reference is the “A Team PCP Tuning Procedures” document, which you can find at http://ateam.alotspace.com/Crosman.htm. This is a lovely writeup by Ray and Hans Apelles, where they describe how they use the Marauder’s mind-boggling tune-ability to reach the sort of shot string and firing characteristics they’re looking for.
-Jan
Off today’s subject a little. Purchased a Bronco with leaper offset mount and 4x bug buster scope. I’m very pleased. The trigger looked a little cheap or funky. But going by what I heard here it sounded OK. Man what a slick trigger for that price point of a gun. It is simply fantastic both my daughters an I love it.
For work I have been sent down to training in Houston for the next 44 days. Missing my shooting I went out an purchase a crosman 1377 (I have 2 of these back home), pellet trap an 1000 pellets. I have a good 25 foot range in the hotel room. My stress is no where to be seen.
By the way when I retire or in my next life I’d like to live next door to B.B. an help him test airguns. Not sure who this Mac guy is I’m jealous of him for sure.
Thanks again for the advice on the Bronco and a superb blog.
I did a little shooting today with light and heavy pellets.
Conditions: bright sun, 88 deg., wind SE with gusts up to 35mph.
Same as usual: 6″ Shoot-N-C targets, 25yd. 30 shots, max. possible score 300.
Crosman Storm XT/ Tasco 3-9x40mm scope. Cabela’s 10.5 gr. domed pellets. 279/300.
Bronco Target Gun. Adjustable peep sights. Beeman pointed pellets, abt. 7.5 grain.
I couldn’t get into the target with these. Way too light for the wind.
Substituted the pellets used in the XT. Adjusted sight for increased pellet drop and wind. 259/300.
Neither score outstanding. But I found that even a low-powered springer like the Bronco does a lot better in the wind with heavier pellets.
I had weighted my target box and had no problem with the wind moving it. It was kind of fun to have to deal with the wind, it puts a real-life factor into the shooting.
Les
Another off topic but I am busting to talk about it! Picked up a screaming deal at a yard sale this past Saturday. A Beeman Tempest!
Shot it a little bit ago. After adjusting the sights and getting used to a sproinger pistol with a heavy trigger, I am starting to get groups approaching 1 inch at 10 meters! I think this one is going to be a keeper!
RR,
Congratulations on your good find! A Beeman Tempest is a great spring air pistol and the more you shoot it the more used to it you will become. Finding one at a yard sale is a major coup!
B.B.
And he threw in a beatup, bedraggled Red Ryder with the deal! I just wish I still had the Webley my father gave me when I was a kid.
RidgeRunner
I got a Tempest at the Roanoke show a couple years ago. I found a trigger tune article for it on the internet but I found with just a simple screw adjustment the trigger is just fine. It’s a fun little pistol and quite good for plinking accuracy, mine came with walnut combat grips. But I’ll bet you got a better deal than I did, I had to give $200.
Loren
With the Red Ryder, I paid $60. It’s not mint, but it’ not bad.
I am interested in a chrony. I do not need all the bells and whistles because I will only take a few shots with each air gun and/or pellet . What is your suggestion?
Thank you very much,
Pete in California
Pete,
I and a number of folks on this blog use the Chrony ‘red’ model now apparently replaced by a ‘green’ model. It’s cheapest and provides the needed information. Most of us have learned to set this up 3 feet or so away from the muzzle and NOT downrange. You lose a lot of Chronys that way. Here is the link on PA’s site. Their pricing is as good as you will find elsewhere:
/product/shooting-chrony-f-1-chronograph-green?a=1174
Heck — if shooting a scoped AirForce model, you can lose one even up close Getting the scope low enough to see under the sky-screens while keeping the barrel high enough to miss the sensors.
Mine has a nasty dent on the front lower metal from a .22 Condor.
I have the blue Beta model, in “Master” configuration. (The “master” variants don’t put the read-out on the lower front panel; they remote it with a phone-cord; that’s all that saved mine from the Condor — otherwise the electronics/control/read-out would have been trashed).
I also added the printer — though I need to see if it still works; I dropped it off the table and spent hours trying to get the print head mechanism back into shape.
BTW: for indoor use, the maker now has a set of red LED lights/screens, rather than those ugly incandescent bulbs. http://www.shootingchrony.com/products_newproducts.htm (hope it’s permitted)
One consideration — the maker allows one to send in lower models for upgrades to higher end versions; you don’t have to buy a whole new unit to gain features. [Or if you shoot the thing to death, you can trade it in on a new model]
Wulfraed,
The only time I ever hit the skyscreens was when I tried to use the scope. Unless you are shooting beyond 20 feet you never need to use the sights to use a chronograph. Just instinct-shoot using the barrel for alignment.
B.B.
Pete,
I own a red Alpha Shooting Chrony, too and think it’s all you need.
B.B.
B.B. and all. I heard of the “Red” years ago. Red now green is OK…and thanks for the tips on how to avoid damage….I think I’ll pick one up, and be very disappointed with the results my air guns are supposed to demonstarte.
Thank you !
Pete
Not so quick, Pete. You may be pleasantly surprised! My first rifle was an RWS 46 which could barely put out 12 ft. lbs. of energy at the muzzle. A year ago when I re-tested it when I guest wrote a blog on which rifle in my collection was the most accurate (it was the Marauder), I discovered my 46 was now putting out over 15 ft.lbs. of energy – a magnum powered rifle. Without a chrony, I never would have known!
Fred DPRoNJ
Thank you, Fred DPROoNJ. Well at my age, we learn to expect disappointment, that way we are never disappointed.. GRIN. OK, I”ll see what happens with the Gamo Big Cat 1200 (My favorite-in-the closet-go-to..) and the Tomahawk ( Ooooh, don’t bump the stock…)..
Stay tuned,
Pete
Great and very interesting blog and the reason that I searched it out was that I’m still experimenting with pellets in my Benjamin Genesis 22 cal.. I do not have a crony, but in shooting at a one inch soft pine board with a Crosman Premier 14.3 grain, a JSB 18.3 grain and a Beeman Kodiak 21 grain. the Crosman and the Beeman Kodiak went clean through the board at 10 meters and the JSB just broke the other side, but did not exit. The Kodiak was the most accurate, which is what I was in search of.
Dan Naylor
While using the same pellet to compare behavior of different guns may be viable… Using different pellets in one gun is less useful.
Consider that a harder pellet will deform less and penetrate further than a softer pellet that expends energy flattening and spreading. And aren’t Crosman Premiers considered a harder pellet?
Wulfraed,
Yes, I understand What you are saying and my original intention was just finding a pellet type that would group the best in my gun. The question about the penetration came up after reading the above article, which stated that a heavier pellet would deliver less foot pounds of energy in a break barrel type gun. Both the Crosman Premier 14 grain and the 21 grain Kodiak had the same amount of penetration at 10 meters. If the heavier pellet is losing energy, it’s not enough to be a concern and so far it has the tightest groups.
Thanks for your comment,
Dan
B.B. In trying different weight pellets in my Benjamin Genesis, it followed close to your findings that with a heavier pellet there was a loss in power. Using a JSB Exact Jumbo Heavy 18.13 grain pellet at 10 meters, I had to aim high by one mil dot to hit the same spot as shooting the Crosman 14.3 grain hollow point. Now my question is in regard to my modified Crosman 1377. When shooting a 7.9 grain Crosman hollow point, or a H&N Sport 10.65 grain pellet at six pumps, they both zero at the same point at 10 meters. I do not have a Crony and I’m curious to why? Your article stated that in a pneumatic air gun will gain energy, but lose velocity. I thought the heavier pellet would have dropped with less velocity.
Thanks,
Dan
Dan,
Maybe 10meters is too close for the separation to be evident? That’s what I believe.
B.B.