Tag Archives: .223 Remington

Ammunition, AR-15, Reloading, Reloading Corner, Rifles

RELOADERS CORNER: Cartridge Evolution

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Here’s a short retrospect on what’s set the standards for most new cartridge designs, and why… KEEP READING

Glen Zediker

ppc

I’m not an engineer, but, like all of us, we rely on those folks to develop just about all the things we have and use. When we look at a new development, one that’s proven to work better than the “old” way, sometimes it’s easy enough to understand why. Cartridge development over the years is a good example.

What makes a good cartridge? Answers, of course, vary with the intended use, the performance needs. For the most part, power (which mostly is velocity), and “efficiency” (which is essentially getting the most from the least amount of propellant, likewise increasing barrel life), and accuracy (always) top the list. And, to me, “accuracy” is a combination of small group sizes and, even more, small group sizes all the time! Consistency.

Case capacity has the most to do with the first: more room for gunpowder means more power. Also, it’s pretty clear that pressures have been going up! There’s a big (big) difference in the pressure levels of some of the “new” cartridges compared to the older, longer-lived rounds. Sometimes it’s not because the older round can’t “take” the additional pressure, it’s because the guns might not. A round developed turn-of-the-century fits a rifle from the same era. Well, steel has improved, manufacturing has improved, and, some no doubt, is that the trend toward “shorter, fatter” cartridge cases also contributes.

So. About that…

In my mind, and certainly in my “world,” which is competitive shooting, one of the most influential cartridges has been, and still is, the PPC. That was developed in 1975 by Ferris Pendell and Dr. Lou Palmisano (hence “Pendell, Palmisano Cartridge”), and the idea was to design the “world’s most accurate cartridge.” They did. It has the record to prove it. However, that’s in Benchrest (capital “B” meaning formal competition). Bechrest is nearly always a 100-yard event. The idea behind the PPC wasn’t to set the range on fire with excessive velocity, although it’s well more rapid than others then popular in that game. The idea was to improve cartridge structure to improve shot-to-shot consistency, and another part of that plan was to extend the duration of load-to-load consistency by slowing down firing-induced changes to the case. It’s native caliber is 6mm (.243).

(By the way, the PPC is based on .220 Russian, which is still how many get their brass: fire form it from that. That round is associated with 7.62X39mm, which came earlier and was based on the WWII German 7.92x33mm Kurz, the Mittelpatrone.)

PPC and .223
PPC isn’t for everyone. It’s expensive and not nearly the fastest available today. However, it sho has had its influence on modern rounds. It’s expensive, by the way, because of the available brass: it’s from Lapua or Norma and has machined primer pockets, and other such points of perfection. Compared to .223 Rem. (right) which, in configuration, follows pretty well accepted architecture, similar to .30-06 and other originally-mil-based rounds, the PPC is shorter, larger-diameter, and longer-necked.

A few reasons, offered by its creators, why PPC shoots so well: One, it’s a short case, a scant 1.515 inches overall. That makes it more rigid and less susceptible to warp. It also means it fits into a short action, also more rigid (and with shorter bolt travel). The case neck is relatively long, which means the entire shank of the bullet is within the neck, never below it. That means no influence from varying cartridge wall thicknesses (the case neck walls can be made near-perfectly consistent), avoiding the case neck “donut” at the neck, shoulder juncture. Its body area diameter is 0.440-vicinity, which is (was) a good deal larger than the more common 0.378 commonly used in Benchrest. Case shoulder is 30-degrees.

About that: Well before the PPC there was P.O. Ackley. Well-known for his “Ackley Improved” rounds, which, pretty much, were standard rounds with a sharper shoulder angle. In sharpening (flattening) the shoulder angle (usually from 23-degrees to 30 or even 40), that also elevated the shoulder, and that increased case volume. More speed! Another benefit of the sharper shoulder was a notable reduction in the “flow” of the brass. That meant less change firing to firing. The sharper angle on the shoulder essentially “caps” the flow in that area.

ackley improved
Dang. These always look so radical, but it’s a proven formula: the Ackley Improved. My Dad used one of these in .270 decades ago (P.O hisseff built his rifle) for elk hunting. Shown is an AI 280 Rem. which nearly equals the power of 7mm Magnum.

Other attributes engineered into the PPC have and haven’t been incorporated into subsequent new cartridges. Notable is the smaller-than-standard flash hole. This requires a likewise smaller sizing die decapping pin. Also, PPC uses a small rifle primer, which is fitting based on its overall round size. Over years, there have been retro-engineered common rounds with small primer pockets and those have worked well. For a spell, over the time it was available, small-primer .308 Win. brass found great favor among competitive shooters. Remington made it. Interestingly (again from a perspective of one who isn’t an engineer) pressures were higher compared to standard loads based on routine large-primer brass. Velocities tended to be more consistent.

Another reason for PPC perfomance is one I don’t pretend to understand, and that is its “efficiency.” That’s all in the science of internal ballistics and I only can attest to its influence. I have been a PPC user (the 22 variant) for a good while. It’s what my main NRA High Power Match Rifle is chambered in (AR15 platform). From virtually the same amount of the same propellant, there’s a solid +100 fps gain over the .223 Rem. The structure of the PPC indeed “works.” From that, and from “those” (High Power shooters), rapidly evolved experimental takes on the essential PPC.

Moving on, rounds like 6BR and 6.5 Grendel are outgrowths of the PPC format (“upgrowths” actually: they’re bigger capacity). We’ve also seen the essential influence in the popular 6.5 Creedmoor and the 6XC, which currently dominate competitive across-the-course and long-range shooting (“standard” long range, not the 2-mile stuff, that would be .375 Cheytak…).

6.5 grendel
Cuzzin to PPC is 6.5 Grendel (left), which grew from earlier experiments by NRA High Power Rifle shooters in creating PPC “tall-boys.”

Looking at semi-auto developments, many of which have been coming at us fast and furious, it’s clear cartridge developers are exploiting these same ideas. There is a (short) limit on what will fit into an AR15 upper receiver, for instance, because, one, it’s a finite amount of space, of course, and, two, there’s a magazine box, and these are related. More power in this platform means a fat case.

Now. I am in no way suggesting anyone run out and tool up for PPC in the next rifle! It can be soundly beaten in the “real world” of our needs from a cartridge. There are similar rounds with more velocity, easier availability, lower cost, and on down the list of desirables. In the next couple of issues, I plan to talk more about some of the newest rounds, but wanted to offer just a little retrospect on where it all came from before getting into where it’s gone!

This article was adapted from content in Glen’s newest book: America’s Gun: The Practical AR15. Go check it out HERE! 

Glen’s books, Handloading For Competition and Top-Grade Ammo, are available at Midsouth HERE. For more information about other books by Glen, visit ZedikerPublishing.com

Check out AckleyImproved.com

Ammunition, AR-15, Industry News, New Product, Optics, Tactical Gear, Tactics & Training

REVIEW: Springfield Armory SAINT

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We have been waiting a long time for Springfield’s AR15 and it is worth the wait, and worth the money. Here’s why…

by Bob Campbell

Springfield’s ads had been teasing us with the introduction of a new product and very recently we learned that the SAINT was an AR15-type rifle. This is the first-ever AR15 with the proud Springfield Armory stamp. The rifle had been described as entry level but this isn’t really true. There are more expensive rifles but the Springfield isn’t cheap — it is simply below the $900 threshold. That is a pretty important price point. The rifle has good features and is built for reliability. The SAINT is intended to appeal to the young and adventurous and to those serious about taking responsibility for their own safety. I agree but older shooters such as myself who are able to discern quality at a fair price will also appreciate the SAINT. As a Springfield fan, the SAINT will take its place beside my 1903 Springfield and the modern 1911 Operator handgun, but there is more to the puzzle than the name. At present I have fewer than 600 rounds fired through the SAINT but the experience has been good. (I fire the rifles I test for real on the range, and not with the typewriter. I know the difficulty in firing one thousand rounds or more in an economic and physical sense.)

SAINT and 1903
The SAINT is shown with a 1903 Springfield. A proud tradition!

Let’s look at the particulars. The SAINT features the A2-style front sight/gas block and a folding rear sight. The rear sight is stamped with the Springfield “crossed cannons” emblem. The rear sight isn’t target grade but it is useful for short-range defense work and snagging predators to perhaps 100 yards, the use I will put this 6-pound, 11-ounce rifle to. The gas system is a mid-length architecture. Without getting into a discussion that would fill these pages all its own, the mid-length system is ideal for use with common bullet weights. The SAINT has a 16-inch barrel chambered for the 5.56mm NATO cartridge. This means you can fire .223 Remington or 5.56mm cartridges without a hint of trouble. Its 1-in-8 inch barrel twist is increasingly popular. Midway between the 7- and 9-inch twist this barrel twist rate has proven accurate with the majority of loads I have tested. So far this includes loads of 52 to 77 grain bullet weights.

SAINT
The SAINT handles well. The author found the SAINT exceptionally controllable.

The trigger is a GI-type that breaks in my example at 6.7 pounds. This is in the middle-ground for an AR trigger and it is clean and crisp. There is also a special coating that allows the trigger group to ride smoothly. The receivers are anodized aluminum, no surprises there, but the bolt carrier group is also specially coated, and stamped with the Springfield logo. I like that a lot. Springfield has added a new design with the Accu-Tite Tension system. This is a set screw located in the lower receiver that allows the user to tighten the receivers together. I like this feature and I probably will not add any other tightening measures to the SAINT. The furniture is Bravo Company and the handguard is a Springfield exclusive. The three-piece handguard features a heat shield in the lower base, and allows for accessory mounting via a keylock system. The handguard offers excellent grip when firing but doesn’t abrade the hand when firing in long practice sessions. I like the stub on the end of the handguard that prevents the hand from running forward onto the gas block. Optics are not optimally mounted on the handguard since it isn’t free-floated, so the receiver rail is available for mounting optics. The six-position stock utilizes a squeeze lever for six-point adjustment. The grip handle is the famous BCM Gunfighter.

SAINT sights.
The front and rear sights are adequate for shorter-range use, and the controls are excellent. Note bumper on handguard to prevent the hand running forward off the handguard.

To begin the evaluation I filled several magazines with Federal Cartridge Company American Eagle cartridges. The rifle had several hundred rounds through it and I expected the same performance for this Shooters Log test. These 55-grain FMJ cartridges burn clean, are affordable, and offer excellent accuracy in a practice load. I loaded the supplied MagPul magazine and a number of other various magazines I had on hand. The bolt was lubricated. AR15 rifles will run dirty but they will not run dry. I addressed man-sized targets at 25 and 50 yards, firing as quickly as I could get on target and align the sights. Keeping the hand forward on the handguard (and avoiding the gas block!) and controlling the rifle fast and accurate hits came easily. The rifle is controllable in rapid fire but then it is an AR15… The sights are adequate for the purpose. The Gunfighter grip is particularly ergonomic allowing excellent control. As for absolute accuracy with the iron sights, it isn’t difficult to secure 3-shot groups of two inches at 50 yards, par for the course with an iron-sighted carbine.

Accuracy Testing
For a complete evaluation, you have to go further with accuracy testing and this means mounting a quality optic. I settled down with a mounted Lucid 6x1x24 rifle scope. This optic provides a good clear sight picture and has many advantages a trained rifleman can exploit. I settled down on the bench and attempted to find the best possible accuracy from the SAINT. Hornady has introduced a new line of AR15 ammunition. Since black rifles run on black ammunition the new loads should prove popular. My test samples of Hornady Black Ammunition featured the proven 75-grain BTHP. This is a good bullet weight for longer-range accuracy and it proved to give good results in the SAINT. I also tested a good number of popular .233 loads including a handload of my own, using the 60-grain Hornady A-Max bullet.

Meopta MeoRed
The Meopta MeoRed Red Dot gave good results.

I have also mounted a MeoRed red dot with excellent results. For use to 50 yards this red dot offers good hit probability and gets the Springfield up and rolling for 3-Gun Competition.
I like the Springfield SAINT. I drove in the rain to get the rifle and was at the door at my FFL source when they opened. I had to wait to hit the range! I am not disappointed and the SAINT is going to find an important place in my shooting battery.

Check out the complete specs HERE

SAINT free-float
The SAINT is also available with a free-floating handguard tube.

Bob Campbell is an established and well-respected outdoors writer, contributing regularly to many publications ranging from SWAT Magazine to Knifeworld. Bob has also authored three books: Holsters For Combat and Concealed Carry (Paladin Press), The 1911 Semi Auto (Stoeger Publishing), and The Handgun In Personal Defense (The Second Amendment Foundation).

Ammunition, AR-15, Reloading, Reloading Components, Reloading Corner, Rifles

RELOADERS CORNER: Barrel Twist Rate

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Understanding the relationship between bullets and barrel twist helps prevent mistakes. Here’s what you need to know…

Glen Zediker

Sierra 90gr MatchKing

Why am I devoting this space this time to such a topic? Well, because it’s commonly asked about, and, no doubt, because it influences some of the decisions and options faced in choosing the best-performing load for our needs. Making a mistake in choosing twist can limit both the selection and performance in the range of usable bullet weights and styles.

First, barrel twist rate is a component in the architecture of the barrel lands and grooves. The lands and grooves form a spiral, a twist, that imparts spin to a bullet, and the rate of twist is expressed in terms of how far in inches a bullet travels to make one full rotation. “1-10” (one-in-ten) for example means “one full rotation for each ten inches of travel.”

Bullet length, not weight, determines how much rotation is necessary for stability. Twist rate suggestions, though, are most usually given with respect to bullet weight, but that’s more of a generality for convenience’s sake, I think. The reason is that with the introduction of higher-ballistic-coefficient bullet designs, which are longer than conventional forms, it is easily possible to have two same-weight bullets that won’t both stabilize from the same twist rate.

70gr VLD
Good example: 70-grain VLD (left) needs an 8; the Sierra 69-grain MatchKing next to it does fine with a 9. It’s bullet length that determines the needed twist, not just weight.

The M-16/AR15 barrel changes give a good example. Short history of mil-spec twist rates: Originally it was a 1-12, which was pretty standard for .224-caliber varminting-type rounds, like .222 Remington, which were near-universally running bullet weights either 52- or 55-grain. That worked with the 55-grain FMJ ammo issued then. Later came the SS109 63-grain round, with a bullet that was a bit much for a 1-12. The military solution was total overkill: 1-7. That’s a very fast twist.

Commercially, the 1-9 twist became the standard for .223 Remington for years. It’s still popular, but is being replaced, as far as I can tell, by the 1-8. An increasingly wider selection of barrels are done up in this twist rate. I approve.

1-8 twist.
Generally, well, always actually, I recommend erring toward the faster side of a barrel twist decision. 8 is becoming a “new standard” for .224 caliber, replacing 9 in the process. Reason is that new bullets tend to be bigger rather than smaller. Don’t let a too-slow twist limit your capacity to exploit the promise of better long-range performance.

I’d always rather have a twist too fast than not fast enough. For a .223 Rem. 1-9 is not fast enough for anything longer than a routine 68-70-grain “magazine bullet,” like a Sierra 69gr MatchKing. 1-8 will stabilize any of the newer heavier bullets intended for magazine-box cartridge overall lengths, like a Sierra 77gr MatchKing. An 8 twist will also shoot most of the longer, higher-BC profiles, like the Sierra 80gr MatchKing (which is not intended to be assembled into a round that’s loaded down into a magazine).

Other popular calibers have likewise edged toward faster and faster “standard” twist rates, and that includes 6mm and .308. Once those were commonly found as 1-10 and 1-12, respectively, but now there’s more 1-7s and 1-9s offered. Reason is predictable: longer and heavier bullets, and mostly longer, have likewise become more commonly used in chamberings like .308 Winchester and 6XC.

The tell-tale for an unstable (wobbling or tumbling) bullet is an oblong hole in the target paper, a “keyhole,” and that means the bullet contacted the target at some attitude other than nose-first.

Base your next barrel twist rate decision on the longest, heaviest bullets you choose to use, and at the same time realize that the rate chosen has limited those choices. If the longest, heaviest bullet you’ll shoot (ever) is a 55-grain .224, then there’s honestly no reason not to use a 1-12. Likewise true for .308-caliber: unless you’re going over 200-grain bullet weight, a 1-10 will perform perfectly well. A rate that is a good deal too fast to suit a particular bullet may cause damage to that bullet (core/jacket integrity issues), and I have seen that happen with very light .224 bullets, like 45-grain, fired through, say, a 1-7 twist. At the least, with that great a mismatch you might not get the velocity up where it could be.

.224 bullet extremes
Clearly, these don’t need the same barrel twist to attain stability: the bigger bullet needs double the twist rate that will fully stabilize the smaller one. There’s quite an extreme range of .224-caliber bullets, like this 35-grain varmint bullet and 90-grain match bullet. Now. Do not fire the little bullet in the big bullet’s barrel! It probably would not make it to the target… Swap barrels and bullets and the big one will likely hit sideways.

Bullet speed and barrel length have an influence on bullet stability, and a higher muzzle velocity through a longer tube will bring on more effect from the twist, but it’s a little too edgy if a particular bullet stabilizes only when running maximum velocity. My failed 90-grain .224 experiment is a good example of that: I could get them asleep in a 1-7 twist 25-inch barrel, which was chambered in .22 PPC, but could not get them stablized in a 20-inch 1-7 .223 Rem. The answer always is to get a twist that’s correct.

Effects on the load itself? Yes, a little at least. There is a tad amount more pressure from a faster-twist barrel using the same load, and the reason is initial bullet acceleration is slower.

The preceding was adapted from Glen’s newest book, Top-Grade Ammo, available here at Midsouth. For more information on this book, and others, plus articles and information for download, visit ZedikerPublishing.com