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> Hydrostatic Shock on Small Game and Varmints
Hydrostatic Shock on Small Game and Varmints
@ 05:31 am (GMT) |
Ryan NafeFellas,I have been thinking about how the weight and the mass/volume ratio of game animals affects the cutoff points for hydrostatic shock with a given bullet diameter, SD, and velocity. That lead me to think of a question that I haven’t found any answers to: Would relatively small animals like coyotes, squirrels, and raccoons be susceptible to hydrostatic shock from 30-40 grain hollow point 0.224” diameter bullets at the impact velocities generated by a .22 Magnum rifle? These velocities (for the sake of argument) could be 2,000 - 1,600 FPS. Obviously on medium game like Whitetail deer these bullets would not achieve that, but a coyote or raccoon is so much dramatically smaller than a deer that I thought it could dramatically change the requirements for velocity, SD, and diameter of the projectile with regards to hydrostatic shock. Has anyone done any research on this? Anyone have any observations they’ve made? I have killed quite a few small animals with a .22LR but I’m strongly considering a lever-action .22 Mag in the interest of a flatter trajectory and a large increase in game weights that can be cleanly killed with that rifle. Many people seem to find the .22 Mag to be perfectly adequate for ~50lbs. and under animals out to 100 yards, despite its significant loss in power compared to most centerfire .22’s. Thanks guys. |
Replies
@ 07:10 am (GMT) |
Nathan FosterRe: Hydrostatic Shock on Small Game and VarmintsHi Ryan, on game weighing around 5kg the magnum can be more emphatic than the .22lr depending on the bullet design.On heavier animals weighing up to 20kg, the magnum is not in any way emphatic and can be a poor performer with body shots. Its virtues lie in its flatter trajectory. For game weighing around 10-20kg, it can be used to neck shoot with a somewhat higher degree of authority than the .22lr. But with both head or neck shots, there is still no great room for error. For home killing butchery services of yarded animals, the magnum tends to be much more reliable than a .22lr for frontal head shots. To really extract optimum performance from a .22 magnum, it can be nice to take a bolt action rifle, bed it, slick up the trigger and if needed, add a second action screw in one manner or another. However, it is always a punt as one cannot hand load ammo to fine tune accuracy and it can be equally difficult to find a good range of (cheap) factory ammo to experiment with. So such experiments do have a degree of cost risk. But when such jobs turn out well, the combination of a flat trajectory and good accuracy can make the magnum a joy to use on small game. Just keep in mind that while the magnum can be put to use in a range of applications, it is rather humble cartridge. Do not expect wide wounds or any immediate physical reaction to body shots on game weighing 10 to 20kg. It also pays to weigh up the cost of magnum ammo vs .223 ammo if you are looking at extended range work or regular work on game weighing 10-20kg. When all is said and done, it can be cheaper to use a .223 than having a two shot to 1 kill ratio for shooting at ranges beyond 100 yards. Regarding both your buck shot and magnum questions, I have tested both thoroughly while also continually monitoring client results and youth rifle results over several decades. The last .22 magnum I tricked up was only some months ago. With regards to the .22 magnum youth rifles, it is the sort of thing that guys get into for their kids but those who are astute soon realize the limitations of using it for body shooting 20kg game and tend to move their kids on to the .223 as soon as they are able. As always, results vary depending on how one uses a rifle and cartridge. |
@ 07:20 am (GMT) |
Caleb MayfieldRe: Hydrostatic Shock on Small Game and VarmintsI know in my area the 22 mag, .223, and 22-250 are very popular varminting rounds. My only personal experience is with 22LR on squirrels and raccoons. My observations over the years have led me to subsonic solids when hunting squirrels and medium to high velocity hollow points on raccoon. Until reading Nathans books and many of the KB articles I hadn't been able to define the mechanisms at play, but I believe I have now. In the case of squirrels, the slower moving solid is able to transfer more of it's energy into the squirrel resulting in more extensive hydraulic damage. When I hunted with high velocity rounds, even hollow points, I noticed that quite often the squirrel would react in a very stunned manner for a few seconds, and then begin to recover and run off a short distance before expiring. The bullets would pass through imparting some degree of hydrostatic shock that was short lived. I lost more squirrels that were able to crawl off under a log or into rocks than I care to think about. Granted, a headshot was an immediate lights out regardless.I started using subsonic solids and hollow points to much greater effect. The reaction when hit through the body is almost as though they are hit with a hammer. An audible "THWACK" and the squirrel hunches up and falls, kicks a little and that's it. I have lost far, far fewer squirrels since switching to subsonic, and killed them at much greater distances. The slower velocity on the lighter weight animal works well. On Raccoons a higher velocity round is needed due to the much greater body weight. A high velocity hollow point meets enough resistance to begin expanding and transferring energy. Raccoons are tough, head shots are advised in close quarters. |
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@ 08:21 am (GMT) |
Nathan FosterRe: Hydrostatic Shock on Small Game and VarmintsIf you ever get a chance Caleb, try the Winchester subsonic hollow point. We go through tons of it here in NZ as a possum load. It gives the same thump you talk about and mushrooms quite well due to the very wide HP. |
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@ 08:47 am (GMT) |
Caleb MayfieldRe: Hydrostatic Shock on Small Game and VarmintsI will source a few boxes and give them a try. Squirrel season kicks off here in less than a month, so I need to get my Savage MkII worked over and ready to stock the freezer. My first .22 was a Marlin Model 60 that I still have. It does exceptionally well with Remington Subsonic. I have not tried them in my MkII yet. So far the MkII really likes Federal Gold Medal Target. Makes me wish there was a good way to reload 22LR. |
@ 01:37 pm (GMT) |
Warwick MarflittRe: Hydrostatic Shock on Small Game and VarmintsWork it out as a mathematical problem using physics and compare to the center fire velocities. the answer will be in what differs between the different cartridges . If the weights of the bullets are the same then it will be the bullet's different constructions and differing speeds that will have the answer. Don't expect to win a drag race with low horsepower and tiny amounts of torque FORCE =MASS X ACCELERATIONWork-Energy Principle The change in the kinetic energy of an object is equal to the net work done on the object. The answers are in Nathans Book series. Buy the bundle and save money and making miss takes............. .22wmr 50gn only has 260 odd ft lbs of energy @ 1530fps Mv. Its a bloody cruel way to try and murder something. A 223rem has 1200 odd ft lbs of energy @3200fps Mv and your kills if you hit the right spot will be quick and humane. Check this out https://www.huntinggearguy.com/tips/22-wmr-vs-17-hmr/ |
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@ 07:11 am (GMT) |
Nathan FosterRe: Hydrostatic Shock on Small Game and VarmintsHi Caleb, when last I tested the Remington sub HP's, they were 100fps slower than the Winchester (Rem going around 900fps). The Win has a slightly wider meplat, is slightly faster and the powder is slightly more clean burning which is good for keeping semis clean. The Rem HP is deep but the Win HP still produced slightly faster killing. I shot a brick worth of possums with the Rem, then went back to Win. |
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