Compared: The .204 Ruger and .223 Remington
By Chuck Hawks
These two popular varmint cartridges are both based on the obsolete .222 Remington Magnum case. The .223 uses the same bullets as the parent cartridge, but with a slightly shortened case (1.76" compared to the .222 Magnum's 1.85" case length). Most of the reduction was in neck length and the original shoulder angle of 23 degrees was retained, so the actual powder capacity of the .223 is only slightly less than that of the .222 Mag.
The .204 Ruger is based on the full length .222 Magnum case necked down to accept .204" diameter bullets, with the shoulder moved forward and the shoulder angle sharpened to 30 degrees to increase the powder capacity. When the Hornady and Ruger technicians designed the .204, they took this case to its practical limits. If you want higher performance, you will need a bigger case.
Hornady and Ruger did not want to use a bigger case, because an important part of their design criteria for the new cartridge was that it be low in recoil and mild to shoot. These factors are an important part of the .223 success story and the .204 was designed to deliver recoil and muzzle blast similar to the .223 Remington with a flatter trajectory.
The .204 filled a perceived need among varmint hunters and it was an immediate commercial success. It is now loaded by most major ammunition manufacturers and it is available in a variety of bolt action and single shot varmint rifles; the same rifles are usually available in .223 Remington. The .223 remains the world's most popular varmint cartridge by a wide margin, but the .204 sells well. Varminters pondering a new rifle, but who don't want the extra recoil and muzzle blast of larger cartridges, such as the .243 Winchester or .22-250, will usually end up choosing between the .204 Ruger and .223 Remington cartridges.
Varmints are small animals (usually weighing less than 10 pounds) and they are often engaged at long range, so flat shooting cartridges are generally preferred. Great killing power is not required of varmint cartridges, but if small predators such as coyotes (weighing perhaps 25-50 pounds) are also on the menu, killing power must be commensurate.
The small predators are about the largest animals for which either cartridge is well suited. Neither the .204 nor the .223 is a humane choice for harvesting CXP2 game (deer and antelope), although under ideal conditions and with the proper bullets and precise shot placement, either can certainly kill a deer. So can the .22 LR and even the .17 Mach 2, but that is no excuse for using any of these inferior calibers for the purpose.
In this article, we are going to compare these two cartridges based on ballistic coefficient and sectional density, bullet diameter, velocity, kinetic energy, trajectory, killing power and recoil. We will summarize the results, and perhaps reach some conclusions, at the end of the article. We will use Hornady factory loads for the purpose, since Hornady loads similar types of bullets (V-Max) for both calibers and their ballistics are typical.
The specific loads that we will compare are in the Hornady Varmint Express ammunition line. For the .204 we will use the 32 grain V-Max bullet at a MV of 4225 fps (item #83204) and the 40 grain V-Max bullet at a MV of 3900 fps (item #83206). For the .223 we will use the 40 grain V-Max bullet at a MV of 2800 fps (item #8325) and the 55 grain V-Max bullet at a MV of 3240 fps (item #8327). Most of the ballistic information used in this article was taken from the Hornady 2008 Catalog and is based on the use of a 24" SAAMI specification test barrel.
A larger diameter bullet has a greater cross-sectional area (frontal area). Cross-sectional area is not affected by a bullet's weight, only its diameter. Other factors being equal, the larger diameter bullet creates a wider wound cavity and this often results in quicker kills. Here are the actual bullet diameters of our two calibers (in inches).
The larger caliber .223 Remington bullet is superior in diameter and cross-sectional area. This will be to its advantage in killing power.
Ballistic Coefficient and Sectional Density
The ballistic coefficient (BC) of our chosen bullets affects their performance downrange. If other factors such as velocity are equal, the bullet with the higher BC number will shoot flatter.
The heavier a bullet is for its caliber, the higher its Sectional Density will be. In big game calibers, sectional density is an important factor in bullet penetration. However, SD is less important in varmint calibers, because varmint bullets are designed to disintegrate on impact rather than for deep penetration. Here are the BC and SD numbers for the bullets in our selected test loads.
The relatively skinny .204 bullets have an advantage in BC, but the .223 bullets have an advantage in SD. We can anticipate that the .204 bullets will create a little less drag as they fly through the air and, other factors being equal, with non-frangible bullets the .223 should offer deeper penetration.
Higher velocity is the major component of a flatter trajectory. Velocity is also a key factor in computing the kinetic energy delivered to the target. Here is how our selected factory loads compare in velocity (shown in feet-per-second [fps]).
Clearly, the .204's lighter bullet and somewhat greater powder capacity give it a velocity advantage across the board. We will see how this affects other performance parameters.
Kinetic energy powers such things and bullet penetration and expansion and is an important factor in killing power. Here is how our cartridges and loads compare in energy (shown in foot-pounds [ft. lbs.]).
The .204 maintains an advantage in energy, due primarily to its higher velocity. We will soon see how that affects killing power.
The trajectory tables in the Hornady 2008 Catalog are based on a 200 yard zero for both cartridges and computed for a telescopic sight mounted 1.5" over the center of the bore. Varmints are small targets, so the mid-range rise should be held to less than 1.5", a standard that both cartridges meet or exceed. Here are the trajectory figures, in inches.
The .204's higher velocity (along with bullets of decent ballistic coefficient) pays dividends downrange, allowing both .204 loads to shoot flatter and drop less out at 300 yards. Note that the 40 grain .204 bullet is within 0.2" of the 32 grain bullet at all ranges between the muzzle and 300 yards.
There are a great many methods of estimating the killing power of rifle bullets. Obviously, bullet design plays a large part, but because we are comparing Hornady V-Max varmint bullets, that is a moot issue. The most important factor in killing power is bullet placement, particularly in the case of varmint bullets. Hit one of these creatures center of mass and you should have a kill; shoot off a leg and you have a wounded animal no matter what caliber bullet you used. For our purposes here, we are going to assume proper bullet placement.
In their 2008 catalog, Hornady published their measure of killing power. They call it H.I.T.S., which stands for "Hornady Index of Terminal Standards." That is a rather arcane name for what is actually a pretty good method of comparing the killing power of various rifle calibers and loads. The H.I.T.S. system includes such factors as impact velocity, BC, SD, bullet weight and bullet construction and is based on a 100 yard impact. Here are the H.I.T.S. numbers for our selected loads.
Here the.223 comes to the fore, although all of these loads are entirely adequate for shooting varmints no larger than groundhogs. In the .204 Ruger, the 40 grain bullet is clearly the more effective choice. Comparing the two loads using 40 grain bullets, the .223's greater cross-sectional area gives it an advantage in killing power despite the higher velocity of the .204 load. The relatively heavy 55 grain .223 bullet is clearly the best choice for larger animals, such as coyotes and other small predators, and that is the load that I use in my .223 predator rifle and my .223 varmint rifle.
Kick is the bugaboo of all hunting rifle cartridges. No varmint load is actually a heavy kicker, but recoil disturbs the rifleman's aim and its effects are cumulative and tiring. Since varmint hunters are shooting at very small targets and may fire hundreds of cartridges in a single day, differences in recoil do matter. Here are some approximate recoil energy figures (in foot-pounds) for our selected loads fired in 8.5 pound rifles, computed from data in the Hornady Handbook of Cartridge Reloading.
Obviously, these are all mild shooting cartridges/loads. For comparison, a .220 Swift rifle shooting a 40 grain bullet at 4200 fps would generate slightly over 4 ft. lbs. of recoil energy and a .243 Winchester rifle shooting a 75 grain bullet at a MV of 3400 fps comes back into the shooter's shoulder with about 7.1 ft. lbs of recoil energy. This helps to explain the popularity of the .223 Remington and .204 Ruger with varmint shooters.
Summary and Conclusion
The data above indicates that, in general, the .204 is the flatter shooting cartridge and the .223 packs more killing power. Both are mild cartridges and, in my experience, very accurate in good rifles. .204 Ruger ammunition and rifles are usually not hard to find, at least in the U.S., but the choice is more restricted than for .223 rifles and ammo. .204 factory loaded ammunition is usually considerably more expensive than .223 factory loads. (The .223 Remington is the best selling centerfire rifle caliber in America.) Ditto for accessories like cleaning rods and tips. If you own a .204 rifle, note that the heavier 40 grain bullet shoots almost as flat as the lighter 32 grain projectile and hits harder. Due to its somewhat lower velocity, it should also be easier on barrels. Extreme high velocity significantly increases erosion and shortens barrel life.
The .223 is probably at its best with bullets heavier than 40 grains; it was originally designed for 55 grain bullets. I have had excellent results with 50-60 grain bullets in my .223 rifles. They often provide superior accuracy and, due to their lower MV, longer barrel life. Heavier bullets of high ballistic coefficient are also less susceptible to wind drift, which is often the bane of the varmint hunter.
Whether you choose the .204 Ruger or the .223 Remington, you will not be making a mistake. Both are fine, even exemplary, varmint cartridges.
Copyright 2008, 2012 by Chuck Hawks. All rights reserved.