Here are 2 good articles.
http://alpha411.########.ca/2009/02/air-rifle-caliber-selection.html
Air Rifle Caliber Selection
By Scott Thomas
I often get asked the question: "What's the best caliber of air rifle to use?" The answer depends on what you are going to be using the rifle for. In this article we will examine the pros and cons of the 3 main calibers available for air rifles which are .177, .20, and .22 caliber. Each caliber is unique and each is good for different types of airgunning.
.177 CALIBER AIR RIFLES
.177 cal is by far the most popular caliber on the market today. .177 pellets are the smallest of the 3 calibers and can be fired at the highest velocities for given amount of airgun energy which results in the flattest trajectory. A flat trajectory means greater accuracy from longer distances. If the main purpose of your air rifle is going to be target shooting then choosing a .177 cal air rifle is a smart choice.
.177 caliber air rifles can also be a good choice for small pest control. With current airgun technology .177 cal air rifles can reach velocities of up to 1250 FPS (feet per second) but most reasonably priced .177 air rifles shoot around 1000 FPS. At these velocities you can easily kill small squirrels, birds and other small rodents. We sell a lot of .177 cal air rifles to customers who want the best of both worlds...they want down range accuracy for target shooting but also want the power to kill small pests. The other nice thing about .177 cal is that you have a lot of different guns to choose from in all price ranges.
.20 CALIBER AIR RIFLES
Some feel that the .20 cal air rifle is the best caliber for overall use. It provides a lot more knock down power compared to a .177 air rifle and the trajectory remains fairly flat. Unfortunately there are not a lot of .20 caliber rifles on the market and they tend to be more expensive because only the higher end manufacturers such as Beeman make them. The hard core airgunners swear by this caliber. The .20 cal (5 mm) pellet can carry 40% more energy than a .177 cal pellet yet the trajectory remains almost as flat. The .20 cal is great for taking down larger small game especially if distance is a factor. A .20 cal pellet (depending on the rifle used) is effective up to about 60 yards. With a good pellet you might be able to increase that by a few yards.
There is no doubt that the .20 caliber is a great caliber. Unfortunately there aren't a lot of options out there and price is a factor. You can buy a Benjamin / Sheridan pump style air rifle in a .20 cal for a reasonable price. This rifle is good for close range hunting (25-30 yards) but lacks power for any hunting at longer distances. If you want a pump pellet rifle for target shooting or close range varmint hunting this would be a good choice. If you are in the market for a top of the line air rifle and have the money to spend you might want to seriously consider one of Beeman's .20 cal rifles. They are top notch and backed by a lifetime warranty.
.22 CALIBER AIR RIFLES
The .22 caliber pellet has a large gain in weight and size over both the .177 cal and .20 cal and has the most down range knockdown power of the 3. One drawback of the .22 cal pellet is that it has the shortest range of the 3 calibers. The effective range of this caliber is around 45-50 yards depending on the pellet. However, you can get within 50 yards of most varmint so range should not be an issue. If you are going after larger pests such as jack rabbit, crow, wood chucks (wild), racoon and others a .22 cal air rifle is going to be your best choice because of its tremendous knock down power.
Several different manufacturers such as RWS, Gamo, and Tech Force make .22 cal air rifles and usually make both .177 and .22 cal versions of their more popular models. If the primary use of your air rifle is going to be hunting then go with a .22 cal unless your primary prey is at a distance of 55 yards or more. If your prey is at longer distances make sure you get a powerful .22 cal rifle such as the RWS 34 with Scope .22 cal air rifle or the Tech Force 99 .22 cal with scope. Get something that is at least 800 FPS.
http://alpha411.########.ca/2009/02/field-use-of-airgun.html
Field Use of an Airgun
By Robert Beeman
Adapted and Updated from Beeman Airgun Guide/Catalog Edition 18, the last edition edited by Robert Beeman
http://www.beemans.net/field use.htm
INCLUDING AIRGUN HUNTING
See note added at the end of this section: "So, what airguns do you recommend now, Dr. Beeman?"
It's hard to say if more adult airgun shooting is done indoors or outdoors at the present time. As noted earlier, there are certainly plenty of reasons for shooting indoors. However, few field activities offer any more relaxation and enjoyment than shooting an airgun The relative safety and quiet of fine airguns allow you to do with ease things that might not even be possible with a firearm You don't have to have formal targets or live game to enjoy a day in the field. Acorns, pebbles, twigs, icicles, etc-all become satisfying casual targets. With a little imagination, you can supply a whole range of easily obtained, inexpensive plinking targets. Neccos, aspirin or saccharin tablets, dry clay balls, hard white mints, soup crackers, etc all give a satisfying disintegration when hit. Use of such targets can help develop the idea of plinking as an acceptable, non-destructive sport. These targets are even biodegradable! One clever idea for real sharpshooting is to put out ripe meat as bait and shoot down the flies or "yellow jackets" which soon buzz around it. If you prefer slower targets, try baiting snails! At greater distances beverage cans will always be popular, but you should try some other targets like "indoor" golf balls, swinging targets, suspended bells, etc. (A few cautions. Be sure that pellets missing your targets will land safely. Be careful of ricochets; shooting glasses or tempered eyeglasses are a must for anyone within the vicinity of any gun. Please pick up used cans and don't litter the bottom of streams and lakes with sunken cans.)
Eliminating rodents, destructive and fouling pest birds like English sparrows and starlings, and even things like locusts and grasshoppers, can also be plenty of sport! As a good outdoorsman, you would, of course, learn which organisms are harmless, or even beneficial, and avoid the temptation of plinking at them. The selective control of pests by the adult use of airguns, rather than the indiscriminate use of traps and poison baits, can be of real ecological value
The BEST discussion of airgun hunting is The Air Rifle Hunter's Guide, by Tom Holzel.
Serious shooters enjoy seeing how well they can shoot with a precision airgun at various field distances. Some fire all four positions; others go to the extent of firing from a bench rest. Using a super tuned sporter or a match rifle under ideal conditions, it is entirely possible to fire 5 and 10 shot groups which could be covered with a quarter-even at 50 yards or so! Bench rest shooting is the ultimate test for shooting equipment, ammunition, and ballistic information. However, do not use firearm bench rest methods for airguns The forearm, especially on spring piston airguns, must be very securely held by the shooter's hand
The use of airguns for small pest control depends largely on knowing what is happening at the point of impact. Information from the ballistics section of this publication can be useful, but it must be extended to field distances. Those shooters, and even some writers, who are still stuck in the "firearm mode" of thinking would say that the more power that you can deliver to the live target the better. However, with at least minimally adequate power, the most important thing is to deliver the pellet exactly. When working with airgun energy levels a well-placed head shot is called for on most pests. Some forms, such as crow, are better taken with a squarely placed mid-chest shot In any case, the lethal area is quite small, perhaps only 1/2" to 1 1/2" in diameter. As an example consider squirrel shooting. Examination of the accompanying tables show that, depending on caliber, you must deliver about 3 FP to a roughly one-inch lethal area The energy/velocity and accuracy tables show that even a .177" match air rifle delivers sufficient velocity up to perhaps 50 yards, but that a hit in the critical 1 " area is extremely unlikely beyond that distance. Thus, potential accuracy is ultimately the limiting factor, and your ability to get that accuracy depends on practice and good equipment Don't minimize the importance of good equipment; no matter how well or poorly you shoot, better sights, a more accurate gun, a better trigger, and better pellets will tighten your groupings
While a scope-sighted, match rifle in the hands of an expert may be the best airgun combination for most small pests, the majority of shooters would probably be better off with an accurate, high power sporter. These guns are suitable for larger organisms; their pellets are less easily diverted by wind and leaves, and have flatter trajectory and better penetration. Round or pointed head pellets are the standard for pest shooting, but flat headed match pellets are often used for taking lighter animals. Match pellets deliver a little less lead but their greater accuracy at close range and their greater impact area is often an advantage Greater ballistic drag does give match pellets less velocity (and less flat trajectory) at field distances as the table shows. Hollow point pellets are extremely effective in delivering maximum impact and in preventing over-penetration.
The really key point in airgun hunting is not muzzle energy, but how well energy is carried out to the prey. The energy/velocity table shows dramatically how heavier, larger pellets keep their energy. The clear winner in energy retention and ballistic efficiency is .25" caliber. Thus, trajectory drop with the bigger, heavier pellets is far less than might be expected. The .25" Crow Magnum, sighted in for 50 yards, keeps that powerful pellet within 2 inches of line of sight to over 55 yards! All factors considered, .20" caliber is probably the best all around choice, with a high power .25" being a good second, or even first, choice for the field.
Basic Field Distance and Estimating Point of Impact
You need a simple system for estimating where your pellet will hit when hunting. The excitement of the hunt and the difficulty of accurately estimating distance make complex systems useless An effective, simple system involves sighting in your preferred gun/pellet combination for their maximum effective distance-your "Basic Field Distance" (BFD) You can determine your BFD's by experimentation. The BFD is the distance up to which the pellet has not been more than two inches above the line of sight. For a top power Beeman R1 in 177" or 5 mm caliber the BFD will be about 50 yards The pellet will pass up over the line of sight from such a scoped rifle at about 8 yards, then go over the line of sight not more than two inches before it comes right down to the line at about 50 yards, and then be about 2" low at 55-58 yards. Thus you simply sight in, roughly and easily, at about 8 yards and fine tune your sighting at 50 yards Practice (and practice!) estimating how far 50 yards is. At close ranges and for shots of about 50 yards, your sights should be about centered on the desired point of impact; at middle distances your sights should be about 1 to 2" low Since you really can't estimate the difference between 50 and 55 yards, and the drop is so great over 50 yards, 50 to 55 yards should be considered your maximum practical range. For a 25" caliber R1 the Basic Field Distance is about 45 yards; the maximum practical range is about 50 yards
Point of impact may be changed by many factors. Low temperature is often blamed for a lower POI, but humidity is probably the more important, but less suspected, factor, higher humidity usually means a higher POI, but humidity is often low at low temperatures, especially temperatures below freezing. And all shooters should remember that shooting steeply upward, or downward, will result in a much higher POI .
Don't overlook careful, intelligent stalking as one of the most interesting parts of the field use of airguns. Getting close enough to small pests for the necessary exact shot can provide the excitement of a big game hunt in a setting much closer to home. Camouflage, low-profile stalking, and patient stands can be as useful in suburban field airgun shooting as they are in wilderness shooting .
Specific Recommendations:
Squirrel, Starling, etc.: Carefully practiced head shots are necessary.
Stalk closely and use a scoped match rifle or use a scoped, high accuracy sporter. Beeman H&N Match, Silver Jet, Crow Magnum, or Silver Bear pellets are preferred for either gun .
Rats: A skilled shooter with a match rifle can make the necessary head shots to about 30 yards. Generally a high velocity sporter would be preferred. Silver Jet pellets are best for penetration at a distance; Crow Magnum and especially Kodiak for maximum impact .
Pest Chasing: Pest elimination and pest chasing are different matters. Here you may be trying to rout orchard-wrecking deer or annoying dogs without really injuring them. Study the extended range ballistic tables carefully. A low velocity air rifle or, much better, an air pistol is called for. Use light, flat headed pellets or our felt cleaning pellets to prevent penetration. Experiment by shooting at a grapefruit, a potato, or the like at various distances to be sure that you are not going to cause unnecessary, cruel wounds. Up close, use only cleaning pellets!
Editor's Note: Please update the above remarks to the current situation for availability of airgun models, pellets, etc.. This chapter last appeared in the 19th edition (1994) of the Beeman catalog. I suspect that such suggestions of shooting living things was not "politically correct" enough for the new ownership of the Beeman company. I hope that you have enjoyed this old article, most of its information is as good as the day it was written.
"So, what airguns do you recommend now, Dr. Beeman?"
Now that we have no ties or obligations to Beeman Precision Airguns, people keep asking me that question! So, to save us both some trouble (we can't carry on a chat line with shooters - we are just too busy writing books, etc)., here are my "unbiased" comments: All of the German and English made airguns sold by Beeman are very good, but the crown jewel of their sporting rifles STILL is the Beeman R1 in .20 or .25 caliber, preferably both! For sporting/hunting air rifles, two of my personal favorites always have been the handy, little Beeman R7 and the Beeman C1, both of which seem to have an almost cult following among those who really know airguns. The present production of the R7 is excellent, but if you can locate a R7 with our San Rafael or Santa Rosa address factory stamped on the receiver - you have a special prize. For extra high power, to supplement your Beeman R1 and R7, get the Beeman Crow Magnum in .25 caliber. In sporting air pistols, the Beeman P1 and P2 pistols really have no equals! For match guns, any of the elegant Beeman/Feinwerkbau airguns are the very best available. Sure these guns may cost one or two hundred dollars more than a gun sporting equal specifications - but if you could buy a Mercedes, which can go 120 miles an hour, for only one or two hundred dollars more than a Ford which can also go 120 miles per hour, and you knew that the Mercedes was so much more satisfying and would last you for the rest of your life - what would you decide that you could "afford"? With airguns, virtually everyone really can afford the best! The Chinese and Spanish airguns have come up quite a bit, but they still just are not in the big leagues! And, no matter how some folks beg consideration for them, I still cannot put any mass production American airguns, with their emphasis on plastic and sheetmetal, up with the higher quality German and English airguns, especially the best German ones. You will spend more time holding and carrying your airguns than shooting them - so get guns that are a joy to hold and look at, in addition to performing long and well! "Just as good as.." or "almost the same as..." are lines leading to reduced enjoyment, reduced performance, reduced durability and life, and reduced long term value!
If I were buying a match airgun today, and I was not going to compete in International competition (and most of our FWB customers just wanted the finest airgun available for fun and informal enjoyment), I would seek out the discontinued Beeman/Feinwerkbau Model 300S rifle and the Model 65 air pistol. It is such a delight for most every shooter not to have to fuss with compressed air or CO2! The 300S and 65 will give you several lifetimes of delight, just "thinking off" shots with truly astonishing precision and accuracy. Have it rebuilt by Beemans every few million rounds! If you can't locate one of those, get a Beeman/FWB 603 rifle and a 103 pistol. (BTW - like many airgunners, I often use a match airgun for hunting, even plinking!) Enjoy!
Which is the best caliber? The answer is simple: there is no best caliber, but the matter will be argued forever. The typical choice is between .177 and .22 caliber. Frankly, decades of experience have led me to believe that there is little purpose for the .177 caliber, except for match guns, which are tradition bound to that bore size and where trajectory and wind effect have no significance, and air pistols. For airguns of any significant power, I would always select .22 caliber over .177, but I strongly believe that .20 (5mm) caliber is a much better choice than either one. If you really want more projectile diameter and weight, try very hard to simply skip over .22 caliber and get the much superior .25 caliber - but I would always recommend .25 caliber as an addition to having a fine .20 caliber airgun, not as a substitute. At the time we sold the Beeman business in 1993, .20 caliber had just become our biggest seller and .25 caliber outsold .22 by ten to one! (The emphasis on these calibers was not stressed by the new owners, so the bulk of sales reverted to .177, which is the only caliber understood, or asked for, by most quite unknowledgeable sales reps and chain stores! Sigh! It is now up to good airgunners to really let the makers and sellers know that you want something more than the less-than-dynamic-duo of .177 and .22 calibers! Speak up and often!). Tom Holzel, who may well be the world's leading expert on hunting with airguns, is a very strong supporter of .25 caliber. Tremendous experience in the field, especially crow hunting, has shown him that the the size of the kill zone increases significantly with caliber, meaning you can make a less accurate hit and still assure a clean kill. Practically, this means you can shoot at greater range with the larger calibers. However, you need an airgun delivering at least 20 ft. lbs. of muzzle energy to really take advantage of the .25 caliber pellet. An noted above, the clear winner in energy retention and ballistic efficiency is .25" caliber. In such guns as the Beeman Crow Magnum and RX-2, and many others, it also tests as the most accurate of the four calibers.
Then, after, and ONLY after, you have have a good deal of experience with the excellent .20 and .25 calibers, you owe it to yourself to add some of the really large airgun bores: 9 mm (.38 caliber), .44, etc. to your growing airgun battery.
If after having some top quality springers, you decide to add a PCP rifle: As noted, my main interest in PCP rifles now is centered on the PCP carried by Lewis and Clark in their expedition of 1803-06 which was the key to the West being part of the USA. (See Lewis Air Rifle – New Evidence on this website.). Most of the PCP airguns that I buy are about 200 years old! If I were buying a current PCP I would either get the new Weihrauch 100 PCP repeater from Beeman Precision Airguns (
www.Beeman.com), but far more likely, I would start payments on one of the incredible, top of the line PCP guns featured at
http://www.glbarnes.com/catalog.html . . Your really, really best bet would be to get the HW PCP airgun now and start payments on one of those Gary Barnes PCP’s to be delivered when you will have about two more years of experience with PCP and will really appreciate the incredibly wise steps that you have taken! The HW gun is a good step up in quality from the better RWS rifles (the Chevys of the trade) and the Barnes gun a quantum leap up. (We have NO connection with either of these companies, except getting brownie points – so please mention that I sent you!)
P.S. For a short, but excellent, note on using the Beeman R1(and caliber and pellet selection) for hunting, click on this website link by Tom Holzel, the original airgun hunting wizard:
http://www.velocitypress.com/pages/Woodchucks.php Be careful about reading some of Tom's wild personal info bombs, listed in the left column of his website. You just might blow a brain cell or two!!
And, try to find a copy, or request an interlibrary loan, of Jock Elliott's wonderful article "A Perennial Favorite - The Beeman R1" in the January 2005 issue of The Accurate Rifle magazine. He feels that, even a quarter of a century after it was introduced, this is the air rifle by which others are measured!
