January 04, 2011
By Layne Simpson
Factory Ammunition Accuracy Has Evolved...The accuracy potential of factory-loaded ammunition has come a long way.
By Layne Simpson
The rail gun used to accuracy-test .223 factory ammo is no more accurate than a rifle built for benchrest competition, but it is easier to shoot accurately over a long test session.
We shooters take many things for granted, and the overall quality and accuracy of factory ammunition is one of them. Compared to today, factory cartridges available to hunters during the early 1900s left a lot to be desired in several ways. Many a deer and antelope lived to roam another day due to hangfires and even misfires of ammunition, and it was quite common during extremely cold weather.
There was also the matter of accuracy. In those days 4 to 5 inches at 100 yards was considered entirely acceptable for most deer rifles. I know this to be true not because I was around during that time, but because during the 1950s and on into the 1960s old boxes of ammunition made as far back as the 1920s were commonly found at gun shows. If the container was damaged, or if a few cartridges were missing, it had very little collector value in those days, so the asking price was often quite low. I used to occasionally buy a box and compare its accuracy with fresh ammunition in some of my old rifles. Some of it proved to be surprisingly accurate, but I recall that my 1920s Sedgley Springfield in 7x57mm Mauser averaged 5 inches or so with ammunition made about the time it was built, but average group size would shrink to about 2 inches when I switched to fresh ammo loaded during the 1960s.
But the ammunition companies did not rest on their laurels, and accuracy continued to improve through the decades. As proof of just that, today that same old Springfield will consistently shoot three bullets inside an inch on a diet of Federal Premium ammo loaded with the 140-grain Nosler Partition bullet.
Cartridges made during the early 1900s were not as weatherproof as those made today, and metallic cases were sometimes weak and brittle as well. Hunters were plagued with case separation during firing often enough to prompt some to carry a small device called a broken shell extractor in the field. For the benefit of those who are not familiar with this problem, the head of the cartridge exits the chamber when the bolt is retracted, but the body of the cartridge remains stuck firmly in place. The shell extractor looks like the head of a cartridge case with a shaft containing expanding steel fingers extending forward from its front surface. When chambered, those fingers reach through the body of the case and engage its mouth. Retracting the bolt of the rifle extracts the shell extractor and the case body.
Having one of those handy little gadgets in the pocket of a hunting coat was a wise thing to do back then, and it is not a bad idea even today if you hunt with a rear-locking rifle (such as the Savage Model 99) and try to squeeze too many reloads from a case. It is totally unnecessary with modern factory ammunition. I have been in this shooting game since the 1950s and have yet to experience a separated case with factory ammo. In the old days a company by the name of Echo made broken shell extractors for most of the popular cartridges, and I still occasionally see used ones for sale at gun shows. They are still available from Brownells but only for the .223 Remington, .308 Winchester, .30-06, 7.62x39mm Russian, and 7.62x54R.
Until Remington introduced the Kleanbore primer during the 1920s, hunters and shooters were plagued with rusty rifle bores caused by corrosive primers loaded in factory ammo.
Regardless of whether you want to reduce recoil, increase velocity, defend your home, or win a rifle match, factory loads for those and other applications are available. Numerous brands, styles, and types of bullets are available in factory ammunition.
There was also a time when factory ammunition was loaded with corrosive primers, and any hunter who neglected to thoroughly clean the bore of his rifle soon after it was shot would be rewarded with rusty lands and grooves. Remington eliminated that problem during the late 1920s with the introduction of the Kleanbore primer, and other ammunition manufacturers followed suit. Most shooters today know that even when used with modern ammo loaded with non-corrosive primers, a rifle should be cleaned soon after it is shot, but even if not cleaned, it will go for quite a long time without rusting.
We are also blessed with a variety of specialty cartridges and specialty ammunition. If you are interested in shooting small groups on paper at great distances, cartridges such as the 6.5 Creedmoor and 6.5-284 Norma may be your cup of tea, and both are excellent big-game cartridges to boot. Extremely accurate match loadings of older cartridges, such as the .308 Winchester and .30-06, are also available. Other specialty loadings range from reduced-recoil loads called Managed Recoil by Remington to increased-velocity loads called Superformance by Hornady and High Energy by Federal. The vast number of ammunition options available for various cartridges is great for shooters, but it has to drive a gunshop owner nuts in his attempts to keep the shelves stocked with what customers want. Between Hornady, Federal, Winchester, Remington, and Black Hills, there are over 50 loadings of the .223 Remington and a whopping 76 loadings of the .30-06 Springfield.
Back in the old days hunters did not have a lot of choices in bullets. When I shot my first deer with a Winchester Model 94 in .32 Special, hunters who preferred Winchester ammunition could choose between the Silvertip and the Power-Point bullets. Or if your favorite ammo came in a green box, it was loaded with the Bronze Point or the Core-Lokt bullet.
Today, those two companies combined offer centerfire rifle ammunition loaded with over a dozen different bullets. Regardless of whether you are after prairie dogs on a western prairie, woodchucks in eastern pastures, whitetails in southern swamps, pronghorn on the sagebrush flats, caribou on the Canadian tundra, brown bear in Alaskan alders, or Cape buffalo on the African veldt, one or more of the ammunition companies has just the right bullet for the job.
Most of the major companies offer economy-grade, standard-grade, and premium-grade ammunition. Winchester, for example, has USA Brand, Super-X, and Supreme; over at Remington it's UMC, Express, and Prem
ier. Federal separates its ammunition groups into American Eagle, Power-Shok, and Premium. I am told that as a rule, all three categories of ammunition from those companies are loaded to the same standards, with the primary difference being in the bullets offered. The more expensive ammo is sometimes more accurate, not because it is necessarily of better quality but because it is usually loaded with more accurate bullets. Bullets available in the middle and higher categories almost always offer superior terminal performance over the economy-grade stuff, and that's especially important to big-game hunters.
A concentricity gauge from Sinclair International was used to check .223 factory ammo for bullet runout.
A dial caliper and a bullet comparator from Sinclair International were used to check for bullet freetravel variation.
To illustrate the quality of factory ammunition, I rounded up several .223 Remington loads and shot them in my rail gun. Built by Tom Hall and later updated by Kenny Jarrett, who used it for several years in Unlimited class benchrest competition, it weighs 65 pounds. It has a sleeved XP-100 action, and its 24-inch Jarrett barrel is 1.250 inches in diameter and has a rifling twist rate of 1:14 inches. While a rail gun is no more accurate than a shoulder-fired rifle built for benchrest competition and fired over sandbags, it is easier to shoot accurately over a lengthy test session. When I am fresh and having a good day, I can shoot groups as small with a bag gun as with a rail gun, but as the day wears on and fatigue begins to take its toll during a long shooting session, group size is more likely to increase with the former. In other words, regardless of how weary its shooter might become, a rail gun never gets tired.
When testing the various .223 loads, I shot the rail gun the same as I did in competition years ago. With an eye on a pair of wind flags I had placed downrange, I waited for a condition that would likely hold long enough to allow me to get off five shots and then squeezed them off as quickly as possible before the condition broke. Shooting in that manner virtually eliminated the influence of wind and breeze on group size. I fired five, five-shot groups with each load and cleaned the bore of the barrel with Tetra Gun powder solvent after each 25 rounds. I then fouled the barrel with a couple of rounds before continuing on with the program.
As physical characteristics of rifle ammunition go, bullet runout and variations in the distance bullets travel from the case before engaging the rifling are considered to be two of the more influential on accuracy by shooters who are seriously into the super-accuracy game. As they see it, each and every bullet in a box of cartridges should have zero runout and be in perfect alignment with the bore when a cartridge is chambered. By the same token, every bullet in a box of cartridges would travel precisely the same distance before engaging the rifling. As I prove each time I sit at my reloading bench, handloaded ammunition properly assembled with standard reloading dies on a single-stage press will have no more than .005 inch bullet runout, and bullet freetravel distance will vary by no more than .001 inch from cartridge to cartridge. It is not uncommon for ammunition loaded by benchrest competitors to have no detectable runout, but accomplishing that requires the use of a precision-machined bulletseating die and case necks turned for a close fit with a tight-necked chamber.
During tests years ago, the author's Sedgley Springfield shot 100-yard groups as large as 5 inches with vintage ammo, but it averages less than an inch with today's Federal Premium ammo.
To check the amount of bullet runout in .223 Remington ammunition, I used a concentricity gauge from Sinclair International, and a dial caliper used with a little gadget called a bullet comparator from the same company told me how much variation there was in bullet freetravel. As can be seen in the accompanying accuracy results chart, bullet runout of the 15 factory loads ranged from a low of .001 inch to a high of .019 inch. Especially surprising is the fact that the load with the least amount of runout was the least accurate in the rail gun and the load with the most runout ranked in the middle of the pack in accuracy. So much for the opinion that bullet runout has a detrimental effect on group size. I continue to believe it does, but I also believe other factors and characteristics are influential enough to cancel it out to some degree. Bullet freetravel variation ranged from a low of .001 inch to a high of .011 inch. Again, the load with the most variation ranked middle of pack in accuracy, as did the load with the least variation.
I also found it interesting that the more expensive ammunition was not always the most accurate. Of the three Remington loads, Express ammo loaded with the old Power-Lokt hollowpoint bullet (which has long enjoyed a reputation for excellent accuracy) was more accurate than the two Premier loads with AccuTip-V bullets. Federal's mid-priced Power-Shok ammo also made a good showing against the more expensive Premium loads, while economy-priced American Eagle equaled the accuracy of the Premium and Power-Shok loads. On the other hand, the rail gun did not like Winchester's USA brand as well as Supreme from that company. Any way you look at it, the fact that all but one load averaged less than minute of angle speaks rather highly of today's mass-produced ammunition. And in case you are wondering, the smallest five-shot group was fired with the Hornady Varmint Express 40-grain V-Max load; it measured 0.114 inch.
Before you draw any permanent conclusions based on all of this, keep in mind that a rail gun will show distinct preferences in ammunition just as a shoulder-fired rifle will. If I were to try those same 15 loads in another rail gun, their accuracy rankings would surely shift around considerably. Factory ammunition can also vary considerably in accuracy from lot to lot, and the least accurate load used in this particular test could turn out to be the most accurate in the next. Even with those variations, factory ammunition loaded in America is as good as ammo loaded anywhere else in the world and a lot better than some.