You know how to prepare the cases—now you need to read what powders, primers, and bullets to use.
If you handload ammo for M14 rifle competition, you need to know how to prepare the cases properly, as we described in the September 1996 issue, and you need to know what ingredients make up a good-shooting reload. It would be easy to say “refer to a good loading manual” and leave you on your own, but that’s not our style. It’s also far removed from reality, because you would be hard pressed to find a loading manual that will provide all the information you need. In contrast, the recipes below will help you build a good reload for the match M14 round.
We’ll worry about bullets after making sure they’re going to launch when we intend them to. Please pay attention to this material and the information contained in the Slamfires sidebar nearby. In short, a slamfire occurs when the free-floating M14 firing pin detonates a primer on a closing, but not yet latched, bolt. Reloading practices probably account for most slamfires. In discussions with a few top M14 gunsmiths, most have said slamfiring is nearly 100-percent ammunition induced. Of the reloading practices that cause the problem, insufficient case sizing (which we covered in September) is the leading cause, but loading bench–related slamfire cures also involve the priming process. Most important is primer choice. Lake City ammunition has a tough primer. The only commercially available primer I know of that’s similar in construction is the Winchester-Western product, which means greater assurance against a slamfire might come from using this brand. Please understand that this is in no way a performance recommendation because other primer brands do just as well downrange, but so do WWs. The very sensitivity that makes the Federal primer a big hit with many target shooters works against it when used in a service-rifle role.
The next primer problem is seating. Unlike most guns, where a high primer doesn’t do much but impair ignition, this condition in the service rifle may provide all the window some M14s need to pop off. Always be sure to seat primers fully to the bottom of the pockets, and, to assist that goal, make sure the pocket bottoms are square and as deep as they should be. Using a primer-pocket uniformer is not a terrible chore provided we get some power to the process. My favorite is the Phase II by Sinclair International, a simple tool best chucked into a drill. The tool is adjustable but comes set at SAAMI specs, which is likely where it should stay. It’s a square cutter that flattens the dome in the bottom of the pocket and sets its depth from the case head. This dome results from the manufacturing process used to form the pocket.
There are also case-trimmer reaming attachments and all do, indeed, ream up a storm. But be sure that reamers follow the case centerline rather than the inside of the primer pocket. Reamed pockets ensure there’s adequate depth to get the primer fully below the plane of the case head. When employed as a replacement for a primer-pocket cleaner, using this tool also rebates normal primer-pocket shallowing from subsequent firings.
Seat each primer fully to the bottom of the pocket, but don’t squash it. That’s a rule for any handloader to follow, whether done for safety or for better performance. To seat each primer fully and not squash it, it’s necessary to be able to feel the primer stop on the pocket bottom. Such sensitivity demands the use of a hand-type priming tool. The press-mounted varieties have too much leverage to feed back the progress of this tiny movement. The best seater I’ve used is another Sinclair product, although I’ll admit that its price puts it into the fanatic class of loading tools. Otherwise, get a Lee primer seater and save some money while still greatly improving priming technique over a press-mounted tool. There are other products in the middle, but I believe none are as nice as the Sinclair and none of the midrange products are noticeably better than the inexpensive Lee item.
Taking A Powder
For the M14 to function, gas from firing is bled into the gas cylinder from a port hole in the barrel. This gas is fed through a corresponding hole in the piston, which has a forward facing (into the cylinder) hollow end. When sufficient pressure has accumulated inside the cylinder and piston, the piston moves rearward, the gas-inlet hole misaligns with the one in the barrel and shuts off additional flow from the port, and the action stroke commences. The piston butts up against the operating rod so that when the piston moves to the rear it moves the op rod back, which, being connected to the bolt, opens the bolt and cycles the action. This means there is a lot of linkage under a lot of pressure.
Design specs call for 12,000 psi port pressure (+/- 2000 psi), which can be defined as the level of pressure that exists when the majority of gas reaches the port. Port pressure is not the same as chamber pressure, nor are there direct corollaries: low chamber pressures do not necessarily mean low port pressures, and vice versa. Slow-burning powders, which generally test to lower chamber pressures in the .308, escalate port pressures beyond the limits. This has to do with the volume inside the barrel, which is increasing in front of the case as the bullet travels outward, and the amount of gas pressure behind the bullet during this journey, which can be greater with a late-blooming gun powder. When port pressure exceeds specs, the piston moves at excessive speed, which moves back the op rod and bolt too quickly and forcibly. The gun gets battered.
Who knows what port pressures are with all available gunpowders, but that doesn’t matter as long as you know the powder-burning rate that defines the upper limit, which is IMR 4064. Look in a good loading manual—there should be a fastest-to-slowest burning rate listed for various gunpowders. Find 4064 and use nothing slower. This is not to say it’s necessary to use a fast powder, because then the same standards apply to the M14 as they do for most everything else. Fast powders can overblow chamber pressures before producing adequate bullet velocity, or port pressure, in a .308 case. The practical speed ceiling is IMR 3031. It’s not necessarily recommended, but it defines the fast end of the scale.
The time-proven powder performer in this rifle is one of the 4895 family: IMR 4895, Hodgdon (H)H4895, and Accurate Arms (AA) 2495BR. These excellent performers are very close in burning rates, although they were listed slowest to fastest. This may be the only easy part of handloading for an M14: finding “the load” is not difficult. It’s already been done. If your M14 does not shoot with 4895, there is something wrong with your rifle.
Some swear by the newer high-energy powders like Hodgdon Varget, and other shooters like ball-type powders such as WW 748 or AA2520. As long as the powder falls within the prescribed burning range above, use what works best under the widest range of conditions.
That said, you should still stay in the upper-middle powder range if possible. Let’s say that’s 2,550 fps at 70 degrees with a 168-grain bullet. That level won’t cause problems when it’s 100 degrees, and it won’t suffer getting to the target if it drops to 50 degrees. It’s possible to get more than 2,550 fps from a 168-grain bullet, but the beating it gives the gun really can’t be justified for a little better wind-drift number.
One lesson I think most service rifle shooters learn is the great importance of predictability. Wind drift is always important, but it’s not everything. Attempting to reduce drift at 600 yards by upping the speed on a 168-grain bullet is often penny-wise and pound foolish, assuming that velocity is already 2,600 fps. If you’ll look at a drift table you’ll see that another 50 fps doesn’t make any difference at 600 (qualified by saying that it’s under the value of a sight click). Bullet choice matters most to wind-drift performance, so change bullets if you want better drift performance—don’t load up on powder.
As discussed last article, the standard for M14 match ammunition is Lake City Match M852. If you compete in National Board for the Promotion of Rifle Practice/Director of Civilian Marksmanship events, your rifle better be able to shoot this stuff, and you better know what to expect from it.
A handload that duplicates LCM M852, therefore, better be in your notebook. Here it is: 168-g Sierra MatchKing at 2,580 fps, seated to 2.800 inches overall length. The powder charge is about 41.5 grains of one of the 4895s over a WW primer in an LC case. Exactly how much powder depends on the powder lot, ambient temperature, and who knows what else. Start building loads for your gun below that powder charge and work up. When you see the velocity near 2,600 fps, stop. If your rifle doesn’t shoot with this load, send the gun back.
Getting the powder into the cases can be accomplished with a powder meter. These devices only dispense a set volume of powder, and in the case of those with an indexing feature, the numbers on the micrometer drum do not stand for grain weights; they’re a reference for repeat use with the same powder.
There should be no good reason to weigh each charge. Exacting consistency in charge weights is probably the least important factor in accuracy, as long as each throw is within 0.10 grains. There are several powder meters I like, including the Redding models, the Custom Products Micro Measure, and the Lee Perfect unit.
Grab a cup of coffee because we’re headed toward a dissertation: When you’ve found a powder-charge weight that works well, you’ve really found a volume of powder. That’s the way powder measurement works. The weight in grains provides a way to record and return (supposedly) to that volume and get those same results again, but so does a good meter. Powder weighs different amounts under different conditions, but if you were to put a tablespoon of powder on a scale, no matter how the weight fluctuated day to day, you would still have a tablespoon of powder. Volume is the consistent element.
Weighing charges may often provide less, not more, consistency. To further qualify this heresy, I’m referring here not so much to weighing each single charge in one loading session, but to weighing charges prior to setting a meter for use in a single session. Changing a meter setting changes the volume dispensed, and if the same volume of powder weighs a different amount on a different day, is changing the volume going to help or hurt the consistency of a load? Also, if you use a standard-type beam scale with a magnetic dampener, that contraption may be worth a 0.20-grain variation itself. To see for yourself, weigh the same pan load several times and watch the pointer stop in different places.
Meter-operation technique should be consistent. Test for yourself the effects of varying strokes. Keep in mind that it’s the next throw that will be affected by a miscued stroke, so just dump that load back in the hopper and go on. Also, leave the handle up after a throw; only return it immediately before throwing the next charge. A jostle or bump in between then won’t affect the next throw. A neat trick to reduce static is wrapping a dryer sheet around the hopper.
While a good meter with a fairly free-flowing powder gives no reason to weigh single charges, there are exceptions. One is large-grained powders, like IMR4064. A hopper full of this stuff has a lot of air space compared to a smaller-grained powder. Weigh each charge. The same environmental conditions may have the same effect in altering the weight of large-grained powders, but in the larger-grained powder, weight will effectively be a more accurate indicator of volume because the volume may not be consistently settled in a meter.
Long Range High Power shooters normally weigh each charge, and that is universally considered to be a requisite. Consistency in velocities shot to shot is a major player in accuracy beyond 600 yards. Keep in mind also that long-range loads tend to feature large-grained powders.
The Case For Big Bullets
Before we get into bullet comparisons, realize that much of what we’ll say is not hard and fast. We’ll have to compare ballistic coefficients (BCs) to see which bullets do what, and therein lies the concern. An incomplete—but adequate for our purposes—definition of BC follows: a bullet with a higher BC loses less speed downrange than one with a lower BC. Also, note that effective ballistic coefficients can change. Published BCs reflect bullet flight (often on a cyber-range inside a computer) under a finite set of circumstances. If you’ve ever had an elevation zero change, like when going to a different range, one reason for that is a shift in BC.
None of the numbers should really matter to the experienced High Power shooter, who will develop his own opinion about the flight of his chosen bullet. But the numbers do pave way for an important idea: Judge a bullet first by group size.
Select one you guess will fly acceptably well and then see if it shoots. If it won’t shoot, it doesn’t matter how well it flies. A good shooter will lose more points at 600 yards to poor accuracy than he or she ever will to wind drift. You should expect an M14 handload that groups under 2.5 inches at 300 yards or under 6 inches at 600 to be a winner.
With that said, bigger is generally better in bullets as in other things in life. The bigger the bullet, the better it flies down the pike. But there’s a limitation to what the M14 will endure. While it’s possible to fire even 220-grain bullets through a bolt gun, the realistic cutoff for the M14 is about 175 grains. Service teams have used 190-grain bullets with varying success for long-range events, but there are frequently piston, chamber, and spring modifications, along with faster-twist barrels, done to allow it. Since this article is about across-the-course shooting, we’ll confine the span of real estate to 600 yards and nearer.
The staple service-rifle bullet is the Sierra 168-grain MatchKing. This bullet has been called the most accurate competition bullet ever, and while benchresters may argue against that conclusion until their butts blister, suffice it to say that the MatchKing shoots very well.
There are other makes and models of 168-grain bullets. Hornady and Speer make theirs, and Lapua offers equivalents. All can be used, but their different nosecone profiles, lengths, bearing surfaces, diameters, and so on, can produce varying results loaded to the same specs. My experience has been that no production bullet shoots better than a Sierra. Custom bullets (Berger bullets, for instance) cost more and sometimes seem to shoot a little better for me.
Various 155-grain bullets available can work and take some buck out of the gun. The Berger 155 LTB (length tolerance bullet) was designed for short-range events which require magazine-fed rounds, like 200- and 300-yard rapid-fire stages. This bullet has a profile similar to that of a Sierra 168, but the “length tolerance” description is a misnomer, in my opinion, since it jumps considerably more to the lands than a 168 MatchKing when both are loaded to fit the magazine
Having disclosed the difficulty of BC comparisons, we’ll commence comparing them. The 155-grain Berger LTB flies about the same as the heavier Sierra 168 because its extra speed offsets its lower bc. I’ve had decent luck with these bullets in my 1-in-10-twist barrel, although a slower twist is reputed to do better.
The Berger 155-grain VLD is much better at 600 yards than the Sierra 168-grain projectile by virtue of its higher BC and higher speed. The 155 VLD can be shot from the magazine, although its spikey profile makes for substantial jump to the rifling and more protrusion into the case than a standard-design bullet. Accuracy may suffer as a result. The Sierra 155-grain MatchKing (aka Palma) is a factual and theoretical compromise between the two Berger 155s: it has better flight characteristics than the LTB and a less severe profile than the VLD. Our suggestion is to try the VLD and Palma bullets at 300 and 600 yards and see how they do on the target.
To really step up your gun’s numbers, you might skip the 600-yard test with the 155 VLD and Palma items and proceed directly to a 175-grain VLD for that distance. The 175-grain VLD bullets, as offered by Berger and JLK, really fly. Stated BC on the Berger, for instance, is .537, which is a whole lot more aerodynamic than anything else that can reasonably be fired in an M14. Loaded to an M118 duplication velocity (2,550 fps), performance is noticeably increased. The new Sierra 175 MatchKing is also an outstanding performer. These bullets work with a 1-in-10-twist barrel and won’t tax the operating system.
Setting Up For Seating
One measuring tool you might find handy is a bullet length comparator. This device provides an accurate way to document the length of a bullet, whether it’s in measuring a bullet length or an overall cartridge length.
Tip to base, hollow-point match bullets can vary a good 0.020 inch because of their ragged tips. A comparator avoids the bullet tip and stops at a point down the nosecone. Comparators don’t follow a standard, which means that each may be unique. That doesn’t matter, though, because a comparator still gives an accurate reading: the number produced becomes your reference only for, as the tool’s name implies, comparing the bullets you use. Since it attaches to a caliper jaw, my ease-of-use favorite is from Stoney Point.
You still need to measure to the bullet tip to establish a setting for magazine-length rounds. Set this OAL using a bullet that appears relatively flat on its nose. The magazine will accommodate a round that’s a little longer than the normally given SAAMI maximum of 2.800 inches, so if you set the flat bullet to 2.800, the others should function fine. Then measure that round with a comparator to get a figure for your notes. Working from this figure will be more reliable than having to repeat the process over should you readjust the seating die. Or, if you take the advice and purchase a good seater, it will have micrometer-style indexing which allows for a reliable return to a setting.
There is merit in experimenting with seating depths for slow-fire rounds. Since slow-fire rounds don’t have to fit the magazine, their bullets can be seated out to longer than 2.800 OAL, which can bring the bullet’s major diameter closer to the lands. Most rifles shoot better when there’s less bullet jump required to engage the rifling than what is given at magazine length, including many which get best accuracy when the bullet contacts the rifling at rest. VLDs tend to respond to this treatment. Be aware, though, that pressure will increase in any rounds so constructed; reduce the powder charge in them at least 0.50 grains before attempting this technique.
The first step in seating-depth experiments is finding the point where the bullet contacts the lands, and I recommend the Stoney Point Overall Length Gauge. This simple tool allows its user to locate and measure the bullet seating depth which touches the rifling. It is much better than smoking up bullets and using trial and error. Get the angled version for use with an M14.
Topping It Off
If you do nothing else we’ve touched on here, then get a good bullet seater. The seater in most two-die sets is nothing more than a generous sizing die with a seating plug in place of a decapping rod. Problem: The seating plug is fixed in place, and the case is unsupported during the press stroke. The case is free to move, and so is the bullet being inserted into its mouth. Thus, the probability of the bullet seating straight is diminished.
The better 7/8-14 thread-in dies, such as those offered by Forster-Bonanza and Redding, use spring-loaded sleeves that protrude below the die base. The case rides up inside the sleeve and is fully supported before the bullet starts to seat. We would recommend buying the Forster-Bonanza over the Redding. It’s just as good and costs considerably less, in our opinion. The “floating” stem setup Lee uses also does a good job in a low-cost die.
There are other 7/8-14 interpretations of the so-called benchrest seater, which, in the form actually used by benchrest competitors, is a “hand” die. The emulation-mode threaded dies can use a fitted neck bushing, and precision machining, to accomplish straight-line seating. They can work very well but are in their element when used with short bullets and low neck tensions, which does not normally describe service-rifle realities. The seating plugs are normally too shallow to contact a VLD anywhere but on its tip, meaning that the bullet is free to wiggle, which certainly detracts from the supposed advantage of this die type.
My experience with hand dies, whether the genuine article or a press-mounted facsimile, ranges from bad to indifferent when used in this application. The Forster-Bonanza doesn’t produce one iota more runout than the $100 seaters I’ve tried, and it is suited for High Power case and bullet dimensions.