If you reload with the utmost precision, painstakingly assembling each individual round with tender, loving care, but your rifle still shoots 3-minute groups at 100, you’ll probably start tearing your hair out in frustration. As I replied to a reader’s query about this recently: I estimate that about a quarter of rifle ammunition being reloaded these days is more accurate than factory stuff, a quarter is less accurate and about half, more or less duplicates factory loads. The reason for this summation is that the accuracy (and effectiveness) of factory-made ammo has improved out of sight in recent years, so that it has become no mean feat to equal it at your reloading bench. But it’s not easy to convince most handloaders that this is true.
Many handloaders are true believers. They are convinced that their handloads will always be more accurate than store-boughten ammo. Every now and then my mail contains letters from handloaders who are puzzled because their pet rifle simply won’t shoot tight groups with their reloads. This subject crops up too often to be a rare occurrence, and there are several reasons why.
By reloading the hunter/rifleman can save considerable money, and shoot more for the same outlay. He can also load special-purpose cartridges, which are not available commercially. These include reduced loads for plinking and small- game hunting with big-game rifles. The most compelling reason for handloading, however, has always been improved accuracy. A few decades ago this goal wasn’t all that difficult to achieve, but that is not always the case today.
Alas, many handloaders still cling to agelong myths. Believing in them is what causes bitter disillusionment when the accuracy of their reloads fails to live up to expectations. For instance, carefully weighing each individual powder charge and selecting a powder type “matched” to a specific cartridge cannot be relied upon to produce the desired effect.
It may come as a surprise to many handloaders, but of all the factors I consider vital to good accuracy – primer selection, uniformity of bullet and cartridge case etc – absolute uniformity of the powder charge is least important. I seldom weigh individual powder charges, even for my most serious varmint loads. The sole exception being if I’m developing loads and working up data for a new cartridge. I’ve found that a minor charge-to-charge variation of 1/2 grain in most cartridges is entirely acceptable and most benchrest competitors would agree. But in small, high-intensity cartridges like, for example, the .204 Ruger, I’d not tolerate more than a 1/4 grain variation with a normal load. Happily, modern volumetric and digital powder measures ensure charges that are accurate to within 1/10th of a grain.
Nor do I go to all the bother of trying to discover the exact charge weight of a given powder that might produce the final degree of accuracy in a given rifle. While I am fully aware that one of the most attractive aspects of handloading is “working up a load” for a particular rifle, actually the benefit of such a chore is mainly recreational. Many serious handloaders are hobbyists, willing to spend unlimited time experimenting with a wide range of components before they find that magical combination that produces tighter groups in their new rifle.
Alas, there are other more mundane factors that can influence the result. Maybe the rifle has undergone a breaking- in period of a hundred rounds or so and settled down to give better accuracy than when it came new in the box. Usually, repeat testing with reloads that initially gave poor performance will result in much tighter grouping.
This raises the question: “How accurate is accurate?” Obviously, the answer varies widely.
A varmint hunter who does most of his shooting on the far side of 300 metres would laugh himself sick at the African dangerous-game hunters concept of accuracy. The former sniper demands at least 3/4-a-minute-of- angle accuracy, while the latter is only interested in minute-of- buffalo accuracy in his big double rifle. A fanatical benchrest competitor might sneer at both of them. The average deer hunter is more concerned about the carryability and handling of his musket than with its grouping ability, and may be happy with 2- minute groups, secure in the knowledge that his outfit will reliably drop every deer he’ll ever shoot at if he does his part. Obviously, there’s no absolute standard of accuracy against which all rifles can be judged. It’s up to each individual handloader to decide, when assembling his load, what degree of accuracy will satisfy the load’s purpose. If he finds he can exceed his minimum standard, so much the better.
Working up an effective load for a rifle is easy enough, but going beyond this to discover the “best” load is not always a waste of time. Sometimes a particular combination of powder type, charge weight, and bullet will cause a remarkable improvement in accuracy. In such an instance, however, the handloader may have rectified an inaccurate part of the rifle. Or, it may happen that the supposedly specially tailored load has accidently corrected a harmful flaw in his own reloading technique.
For example, when I’m checking out a new rifle for a gun review, I will first bench test it with factory ammo, if any was supplied. Then, if the rifle doesn’t measure up to expectations, I’ll try my most accurate handload in that calibre. But if it doesn’t group well,I seldom bother to tinker with the load. Something is amiss with that rifle that will have to be corrected mechanically or by being rebedded . Maybe the load could be adjusted to give better groups, but this would still leave me with a rifle that’s likely to behave erratically. And I’d never dream of taking a rifle hunting that I have no confidence in.
Up to now I’ve been deliberately negative in order to persuade you what not to concentrate on when developing reloads.
One of the first decisions to puzzle the beginning handloader is whether to full length resize the fired case or only the neck portion. Those in favour of neck-sizing point out that when the case expands with firing, it assumes the shape of the rifle’s chamber. Thus, if it is neck-sized only enough to hold the bullet, the case will be a close fit for the rifle’s chamber and ensure precise bullet alignment with the bore, which is conducive to fine accuracy.
This theory is sound enough, but actually there’s a snag to it. If you examine a fired case you’ll notice a bulge about 7mm up from the rim. Because rifles of the same calibre will differ slightly in chamber size, cases fired in different rifles will have been expanded more or less. Also, it may happen that the case has expanded more on one side than the other. This can be caused by the extractor holding the case in a certain position in the chamber or uneven case wall thickness, or simply the way the cartridge lay in the chamber. Obviously, for such a case to fit the chamber exactly for future firings, it would have to be precisely positioned in the chamber. This would be impractical, so a better solution is to full-length resize the case. Sometimes chambers are cut so that they are not concentric with the bore. This makes obtaining fine accuracy next to impossible, but the condition can be made worse by using neck-sized cases.
As a rule, neck-sizing benefits only highly accurate target/varmint rifles with minimum variations in chamber dimensions, and even then the increase in accuracy may be only a few thousanbdths of an inch. So if your rifle is grouping 1-1/2 MoA or better don’t expect any neck-sizing improvement.
And don’t make the mistake of believing that old wive’s tale about neck-sizing giving longer case life. Cases usually wear out when necks harden, lose their elasticity and crack, or the primer pocket gets loose. And cases suffer equal wear whether they are full-length resized or neck-sized. If you decide to neck-size, experiment with the amount of sizing. This
can affect bullet tension and is quite critical. Whenever I decide to neck- size I never resize the whole neck. In small calibre cartridges like the .223, .22-250, .243 etc., I seldom size more than half the neck. But I always full length resize my cases for hunting rifles. The advantages of smooth-feeding, easy-chambering, and quick-extraction are far more desirable than any imaginary benefits of neck-sizing.
This brings us to the argument that rages about how deep bullets should be seated. The beginning handloader can avoid problems in this area simply by seating the bullet so that the overall cartridge length matches that of a factory round. To gain the finest accuracy, however, you may discover that groups will become tighter if you seat the bullet so that it touches or barely misses touching the rifling. If the bullet makes contact with the lands of the rifling, it is pretty well centred and there’s little chance that it will get “cocked” to one side or the other as it starts its passage through the barrel. The further the bullet is from the throat (the origin of the rifling) the more of a jump it must make before engaging the rifling. Thus, it has more of a chance of getting cocked.
But all this is not carved in stone.
The finest accuracy does not always come with the bullet seated so that it touches the lands. Some rifles and loads produce their best accuracy when the bullet is seated 0.020 to 0.040” from full contact with the rifling. But bear in mind that bullet seating depth does play a big part in accuracy and is worth adjusting forth and back. Also remember that a bullet in full contact with the rifling can cause above normal breech pressures. It pays to keep a watchful eye for signs of high pressure when varying bullet depth. Too, seating a bullet out farther for increased accuracy may make the round too long to fit in the magazine.
Some rifles, like the Weatherby Magnums, have freebore which is an extended length of throat. The theory is that free-travel allows the bullet to overcome its inertia, reaching a higher velocity, before it engages the rifling. There are arguments for and against free-bore, but for field shooting it makes little difference. My .270 and .3 Weatherby rifles are freebored and both are exceptionally accurate.
Primer Choice and Seating
I have no set opinion about primers making a vital contribution to accuracy. It does appear that “benchrest” primers may be more accurate than others in certain cartridges, but to say that this is always the case would be wrong. However, it’s true that some makes and styles of primers do tend to work better with certain other components. Once again this calls for experimenting with different primers for each different calibre. Sometimes changing to another primer can make the difference between a wonderfully accurate or pretty ordinary varmint reload. One thing I can be sure about is that you won’t get an improvement in accuracy by using magnum-type primers in non- magnum cases.
Most reloading manuals recommend that you seat your primers to bear uniformly against the bottom of the primer pocket. The problem here is that such a degree of perfection is not always easy to achieve; it’s hard to tell by feel or by measure when a primer is properly seated.
A primer that sits below the lip of the pocket or flush with the base of the case is not necessarily as well seated as it might be. While the priming arms that come with some presses work reasonably well, they may not allow all the precision one might wish for. Primer pockets vary in depth which can make it necessary to change the adjustment of mechanical primer seating tools like the RCBS APS Priming System and Ram Prime that primes on top of the press.
The best solution is to use a hand priming tool made for that specific purpose only. These low leverage plier-type tools allow handloaders to “feel” the primer contact the bottom of the pocket. Precision priming tools are made by Lee, Hornady, RCBS and Forster. One of the finest is the Sinclair Priming Tool which utilizes Lee Auto- Prime shellholders and locks the case head square to the priming punch. It comes complete with housings and punches for small and large primers. It’s expesnsive, but by far the best of the lot.
This discussion covers only a few things you can do to improve accuracy, and are only a start. It would take a big thick book to give a complete rundown on precision reloading. The important thing to realize is that many of the old ideas no longer apply, and no matter how much trouble we go to or how good we think our reloads are, there are ways of making them even better.
This article was first published in Sporting Shooter, April 2011.