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Converting a .223 Rem case into a 300 AAC Blackout round
Nov 5th, 2015 by RoundsReloaded

As a reloader I never, until recently, gave any attention to the 300 AAC Blackout round, mainly because I only reload calibers for which my firearms are chambered in.
As a reloading instructor, I had many people ask me about the 300 AAC Blackout round and, until now, I had always brushed it off as mass hysteria.

Things changed when I started building my own AR-15 rifle. I read something somewhere on the net that made me take a closer look at this round, in a nut shell this is what got my attention: You keep the same AR-15 lower, magazines; same bolt carrier group and same charging handle and only switch the upper and done! You got yourself a new rifle chambered in a 30 caliber round; what a cool idea!!!

Then, as a reloader, I started looking at what it was needed to convert a 223/5.56 NATO shell into a 300 AAC Blackout round and realized that it is easier than you might think, as I am about to show you here below.

If you already reload you already have many of the tools you need, what you will need additionally though are: a mini chop saw and a rig to hold the .223 shell in place while cutting it plus, of course, a set of 300 AAC Blackout dies.

Step 1: Sizing and depriming a 223/5/56 NATO case.

I started by sizing and depriming the shell casing, as I would do if I was preparing to reload another 223 round (Figure 01). At this time is a good idea to check the primer pockets and make sure to clean and deburr the primer crimp, if you are reloading military surplus rounds, they usually have a crimped primer.

Figure 01: .223 REM/5.56 NATO shell casing, sized and decapped

Figure 01: .223 REM/5.56 NATO shell casing, sized and decapped

 Step 2: Cutting the shell casing.

To accomplish this step I purchased an inexpensive mini chop saw with a 2″ blade (Figure 02). It seemed to be a tool made especially for this task. I also bought a jig specifically made to hold 223 cases firmly in position for cutting. It comes already made to accommodate the slight taper of the 223 round so the cut is perpendicular to the shell’s longitudinal axis. This eliminates excessive trimming later. One thing worth mentioning at this point is that the case holding jig was set on the base of the cutting tool by carefully measuring the location of the cut with a caliper and firmly tightening it into position. The mini chop saw and the holding jig are readily available online through various websites including Amazon.

Step 3: Measuring and trimming.

After cutting the case I measured it again to make sure the cut was accurate (Figure 03) and then I proceeded to trim the case (Figure 03) to its final new dimension as per SAAMI specs.

Figure 04: Measuring case after cutting

Figure 03: Measuring case after cutting

At this point I deburred the mouth of the case (Figure 04).

Deburring the case

Figure 04: Deburring the case

 

Step 4: Sizing and priming.

I run the case through the resizing die and I primed the case (Figures 05 & 06).

Sizing the case

Figure 05: Sizing the case

Priming the case

Figure 06: Priming the case

A 300 AAC Blackout case is now ready to load (Figures 07 & 08).

Figure 07: 300 AAC Blackout case

Figure 07: 300 AAC Blackout case

300 AAC Blackout case

Figure 08: 300 AAC Blackout case

 

From this step forward the process is the same as for any other round, that is, charge the case using reloading data found in any reloading manuals, sit the bullet, also selected by using data found in the reloading manuals and finally crimp the mouth of the cartridge.

I have not yet made it to the range to test the rounds I have made, therefore, as for performance the jury is still out.

I will report back once I shoot some rounds downrange. Until then, keep reloading my friends.

The Essence of Reloading – Flexibility
Oct 4th, 2014 by RoundsReloaded

The Essence of Reloading – Flexibility

The great thing about reloading is the ability to build a round to meet the situation. A .45 Colt can become a perfect plinking revolver with a light load. The same gun can halt a rouge bear if the powder and bullet weight are pumped up. Photo courtesy Massaro Media Group and JNJphotographics.

As a reloader, you are able to control the ballistic parameters of the ammunition for your firearm. Whether it is a pistol or rifle, the ability to vary the bullet weight and velocity of your firearm makes each and every one of them much more flexible than most people would think.

There are oodles of great factory loadings available today, and it is better than it has ever been, but we handloaders have the wide world of bullet choices and powder selections at our fingertips.

Take a long look at your favorite rifle, and odds are that you can find a pretty wide choice of projectiles, that can serve in a multitude of different hunting situations. Let’s look at a few examples.

The classic .300 Winchester Magnum can use a selection of .308” diameter bullets that weigh between 110 and 250 grains. That’s quite a wide range, and each weight has its place in the hunting field.

Winchester’s .300 has earned a very good reputation with 180 grain bullets moving along at around 2,950 feet per second and that load is one I use often, especially when the possibility of a long shot exists, like moose across a Quebec lake, or kudu in the karoo of South Africa. Many elk hunters grab this configuration of ammunition, and with good effect.

My rifle loves the 180 grain Swift Scirocco II, handloaded with Reloder 19 to 2,960fps. But, you really don’t need that velocity or the heavy bullet all the time.

Let’s assume you have a .300 Winchester that you absolutely love (which I do!), and want to use it for pronghorn antelope on the Great Plains.

A fast, flat shooting 150 grain bullet will fit the bill perfectly. At 3,150 fps, you should be able to hit those goats out as far as you’d ethically shoot them, and a bonded core spitzer bullet will kill quickly without making a bloody mess.

If you want to take that same rifle deer hunting, a 165 grain bullet loaded to just under 3,000 fps will make a very effective whitetail load, regardless of the distance.

Sometimes, a specialty hunt will pop up that may force you to get creative; bear hunting over bait is one example that comes quickly to mind. The shot will usually be under 75 yards, yet you want something beefy because bears have claws and teeth after all. In these situations, I subscribe to the Elmer Keith “slow and heavy” school of thought.

I took a box of 220 grain Hornady round-nose bullets, and used IMR 4064 to reduce the velocity to 2,425 fps, similar to the older .30-’06 Springfield loads. Group size hangs around minute-of-angle, and these big heavy bullets will really thump a bruin.

As a matter of fact, that particular load has worked very well on whitetail deer as well. My eleven point buck from 2011 fell as if he were pole-axed. He weighed 180 pounds on the hoof.

The plains of Africa can present a diverse selection of game, from the diminutive Steenbok to the moose-sized eland, and you have to carry a load that can cover all the bases. I brought the 200 grain Swift A-Frame, loaded to 2,700 fps in my .300 Winchester and it worked out very well.

The .300 is just one example, and the same could apply to a .30-06, .280 Remington or .270 Winchester. Learn about the different types of bullets available in your favorite caliber, and utilize the different weights and construction available.

Pistols can benefit from the same mentality. My Ruger Blackhawk in .45 (Long) Colt is a very strong revolver, and that cartridge can be stoked up to bark!

The big 300 grain Hornady XTP bullets can be pushed to around 1,300 fps, which is a wonderful insurance policy while hiking in my native Adirondacks or Catskills. The same revolver likes to play cowboy with me though, and when you roll up some 250 grain hard-cast lead Falcon Bullets at a velocity of 850 fps, you can shoot all afternoon at paper hombres.

Lighter bullets like Rainier Ballistics’ 180 grain flat point, which are usually reserved for the .45ACP, can be loaded in the Colt case in either a high velocity situation or in a reduced velocity scenario, depending on the application, or your mood.

The larger caliber safari guns can be rather intimidating to a shooter who doesn’t have a ton of experience with them. The heavy recoil they produce, being a side effect of the big bullets and powder charges, can pose a problem.

Firearms, such as the .300 Winchester, are eminently flexible. Given the sheer amount of components that can be used with the caliber, reloaders can tailor the cartridge to nearly any need. Photo courtesy Massaro Media Group and JNJphotographics.

Reducing their velocity for practice is a wise idea. Drop the velocity by 150 or 200 fps and that recoil drops off quite a bit, making the rifle much more manageable. The classic .416 Rigby launches its 400 grain bullets at 2,400fps, with rather severe recoil. Drop the muzzle velocity to 2,200 fps and you can immediately feel the recoil drop off, yet you still have a potent big game loading.

The most popular chambering in safari rifles is undoubtedly the .375 Holland and Holland Magnum. The 300 grain bullets that made the cartridge so popular are loaded to 2,550 fps in most factory loadings. These bullets are wonderful for buffalo, elephant and brown bear, but that .375 can be used for much more than the big nasties.

Barnes makes a great 235 grain TSX bullet; it’s a solid copper hollowpoint that can be pushed over 2,800 fps. This makes a great long range elk and moose load. It also works well on black bear, and gives you more time afield with your favorite .375.

So, look at the possibilities for your favorite rifle, and don’t be afraid to use you reloading bench to make sure you have the perfect load for the hunting trip you’re planning. There are tons of great bullets and powders out there, and that’s something we reloaders should be very grateful for.

Lack of Concentricity
Jul 18th, 2014 by RoundsReloaded

Lack of Concentricity

Written by Sierra Ballistic Technician Rich Machholz

I have had this experience personally and stumbled across one solution quite accidentally.  Of course there could be several things causing this, so we can explore this one by one.

If your neck is .001″ out before seating a bullet that will be amplified if measured on the bullet after seating.

The solution may be as simple as polishing the upper edge of the expander ball.  Both the seating die AND the sizing die need to be squared to a dedicated shellholder in a dedicated press.

This is not normally an everyday chore, but check it every time by raising the shell holder to the bottom of the die to a light touch and watch to be sure that more than just one side touches.  A light behind the press will help and if just one side does touch, resquare the dies.

If you find a true straight loaded cartridge use it to square the seating die as a quick fix by backing the seating die off and running the ram to the top of the stroke.  Now back your seating stem off to make sure you don’t disturb the original seating depth and screw the die body down until it contacts the crimping ledge in the seating die and back off a half turn.

Set the seating stem snugly against the bullet and tighten the lock ring.  Next tighten up and set the lock ring on the die body and you now have a quick fix.

A GOOD and UNIFORM inside champ here can solve a lot of seating problems, concentricity or lack thereof being one of them.

You can use the deep hole provision of your calipers to check the height of your shellholder as mounted in the ram and the ram itself for squareness.

Or … you can invest in a Forster Co-Ax press and benchrest dies and kiss concentricity issues good bye.  Or find a press that IS square.

Fighting concentricity is very frustrating and to think we didn’t even worry about it 20 years ago, maybe even less than that, but that is also the reason today’s rifles are so outstandingly accurate.

I hope you find the cure to your problem and good luck.

The Myth: The .223 is too Light for Deer
Jul 11th, 2014 by RoundsReloaded

The Myth
The .223 is too light for deer.

The Facts
I read somewhere that today’s premium bullets represent the greatest advance in big game hunting technology since the widespread use of the optical sight, and I agree 100 percent. Many of the myths that we face today are the product of outdated truth—what your grandfather or Elmer Keith said 50 years ago may not be true today. The fact is that today’s premium bullets penetrate deeper, expand more reliably and stay together better than ever before. This has been a game-changer for small calibers (note the resurgence in the .243 Winchester). It’s not that the laws of physics or reason no longer apply, but the fact is that bullet technology has readjusted the scale of which calibers are appropriate for what game. Thanks to these advances, .224 caliber bullets are no longer designed with either varmints or Soviet infantry in-mind. Let’s take a look at factory ammo.

Federal Premium alone lists four factory loads appropriate for deer-sized game, I’m not talking FMJ behind the ear appropriate either—these are legitimate, put-it-on-the-shoulder big game bullets. All of these bullets should shoot well without the need of the fast-twist barrels necessary for the longer, heavier (and excellent) .224 bullets on the market. I’ve personally used three of these bullets in various loads on management whitetails and a truckload of feral hogs—none of them lived to tell about it.

I asked around for some opinions based on more than anecdotal experience. As always, I found a public relations professional willing to answer some questions.

“We would agree that there are adequate loads/bullets for humanely taking deer with the .223,” said Tim Brandt, Federal Premium Public Relations Manager. “We have several .223 loads featuring a couple different bullet options that are designed especially for hunting. Our Fusion line is great example. We see excellent weight retention, expansion and penetration from this bullet in the .223 platform. Hunters that live in areas where it’s legal to use this caliber should have no problem finding an effective load to take into the deer stand.”

Tim also included the following test data, which shows that the average Fusion bullet penetrated nearly 15 inches of gelatin and expanded to .54 caliber. Most of a bullet’s expansion happens within the first inch or so of penetration which means that the Fusion load effectively sends a .54 caliber ball through the vitals of its intended target. I observed recent tests of the DoubleTap load with similar results.

Gelletin

Federal Fusion Rem. bullet fired into 10 percent ballistic gelatin at 100 yards (bullet expanded and penetrated to 15 inches)

Bullet

Five Federal Fusion .223 Rem. bullet expansions shot into 10 percent bare gelatin

One of NRA’s contracted experts, Richard Mann, helped develop the Bullet Test tube. (It’s slightly harder material than the gelatin used in Federal’s test.) Mann tested Federal’s loads in it and on deer, and here’s what he found:

“The .223 Remington is a suitable cartridge for hunting deer, within its limitation. This cartridge relies on velocity to drive the lightweight bullets deep. This same velocity contributes to tissue damage. The key to using a .223 Remington on deer is to keep impact velocities high. In other words don’t shoot deer much beyond 150 yards. Past that distance, the velocity drops below the level needed for dynamic bullet expansion. When robustly constructed bullets like the Barnes TSX, Nosler Partition and Fusion are used inside 150 yards, penetration with the .223 Remington is on par with cartridges like the .243 and the .30-30 Winchester.”

Ok, so we heard from the nerds in the lab coats, what do the guys that shoot deer for a living think? My friend John Shaw has killed more deer than anyone I know—he’s managed an exotic game farm, worked on a Texas whitetail ranch, passionately hunts whitetail in numerous states using the .224 and .22-250. He has also culled scores of does for meat, depredation, and management purposes. John has this to say:

“I rely on my 22 centerfires more so than any other caliber. Low recoil and the typical pinpoint accuracy found in rifles of .224 caliber allow for careful shot placement. If you treat hunting with your .223 much like bow hunting and wait for the perfect shot, there is no reason that this caliber should not be considered for many applications. However, bullet choice is a major factor. Shots to the central nervous system with any type of bullet will work but I recommend premium, controlled expansion bullets, such as Barnes Triple Shocks, Nosler Partitions, and Trophy Bonded Bear Claws. Typically, I keep shots under 200 yards but animals hit in the shoulder, heart, and lung region with a quality bullet expire quickly.”

The Conclusion
I’m not saying the .223 is the perfect whitetail bullet, I wouldn’t pack it on a trophy hunt or where long shots were likely but, with the right bullet, it is a legitimate choice for some big game animals. With big game bullets ranging in weight from 55gr. to 70gr., it’s versatile at a range of velocities.

Long Range Load Development
Jul 9th, 2014 by RoundsReloaded

This article was posted on Sierra’s Facebook page. We found it to be very interesting; so much so that we thought it was worth to be posted in our blog as well. To all the precision long range loaders and the aspiring ones as well, enjoy it. We know that some of us will try this method out.

Long Range Load Development

Written by Sierra Bullets Product Development Manager Mark Walker

walker1

 

Since I just put a new barrel on my F-class rifle this spring, I figured it might be a good time to discuss load tuning for long range shooting. Getting the most accuracy out of your rifle is one of the most important aspects of load tuning. For long range shooting in particular, using a load that produces the least amount of vertical variation is vital. There are several steps to the process that I use, so I will go through the basics of each. When I first get a new barrel installed, I like to determine what the loaded cartridge “jam” length is. I do this by taking an empty case (no powder or primer) that has been neck sized with the proper bushing (I like to shoot for 0.002 smaller than the loaded cartridge neck diameter) and seat a bullet long in it so that the throat of the rifle will move the bullet back into the case when I close the bolt. I close the bolt several times until the bullet stops moving back into the case at which point I use a comparator with my calipers and get a length measurement on the cartridge. This is what I consider to be the “jam length” for this barrel and chamber. I came up with 3.477 as the “jam length” for this particular barrel. Next, I will fire form some brass using a starting load of powder and bullets seated to “jam” while breaking in the barrel. My barrel break in process is not very technical; it’s mostly just to get the brass formed and the rifle sighted in. I do clean every 5 rounds or so just because I feel like I have to. Once I have the brass formed, I use them to load for a “ladder “ test to see what powder charge the rifle likes. With a ladder test, you take your starting load and load one round each with a slightly increasing amount of powder until you reach your max load for that cartridge. You then fire each round using the same aiming point to see where the bullets start to form a group. For this barrel and cartridge, I started at 53.3 grains of H4831SC powder and increased the load by 0.3 grains until I reached 55.7 grains. I always seat my bullets to “jam” when doing a ladder test. We will determine the final seating depth in another test later. It’s usually best to shoot this test at a minimum of 200 yards because at closer ranges the bullets will impact too close together making it hard to determine which load works best. I shot this test at 300 yards.

walker2072-copy

 

As you can see from the target, the lightest load #1 had the lowest velocity and impacted lowest on the target. Shots #2 and #3 were a little higher and in the same hole. Shots #4 thru #6 were slightly higher yet and all had the same elevation. Shots #7 and #8 were the highest on the target however pressure signs were starting to show. For some reason shot #9 went back into the group and the chronograph didn’t get a reading so I ignored that shot. When picking a load, I am looking for the most shots at the same vertical location on the target. As you can see that would be shots #4 through #6 so I would pick a powder charge from those shots which would be 54.2 grains to 54.8 grains. As a side note, shots #2 and #3 are only 0.851 lower so I wouldn’t be afraid of using one of those loads either. I settled on 54.5 grains as the load I wanted to use. It’s right in the middle of the group so if the velocity goes up or down slightly, the bullet should still hit in the same place on the target. Now that we’ve settled on a powder charge, I want to find the seating depth the rifle likes. I usually start at jam length and move the depth in 0.003 until I get to 0.015 deeper than jam. I load 3 rounds at each depth using the 54.5 grain powder charge and shoot a group with each depth at 150 yards. As you can see from the target, the first two groups are not good at all. Next one looks good and is the smallest group on the target. The next three are not quite as small but the vertical location on the target is almost the same which indicates a sweet spot which will help keep the vertical stringing to a minimum on target. I went with 3.470 which is right in the middle once again and should give some flexibility with the seating depth.

walker3074a

 

So after all of that, my load is 54.5 grains of H4831SC and a cartridge length of 3.470. I plan on loading up enough ammo to shoot five groups of five shots and see exactly how this load works on target as well as what the extreme velocity spreads are over several groups. I sincerely hope some of this information helps you to get the best accuracy out of your rifle. I do not take credit for coming up with any of this, a whole lot of good shooters use this same method or a variant of it when working up their loads. For more information about load development, please contact the Sierra Bullets technical support team at 1-800-223-8799 or by email at sierra@sierrabullets.com.

Disclaimer: Load data represented here may not be safe in your rifle.

 

Cartridge Crimp Styles and Uses
Jul 4th, 2014 by RoundsReloaded

Cartridge Crimp Styles and Uses

Lee 3-die set with taper crimp die.

Crimping, that final stage of handgun cartridge assembly. Whether done as a separate operation, or as a part of the bullet seating process, one simple fact remains – it must be done.

There are two distinct types of cartridge crimps: Roll crimping and taper crimping.

In the handgun world, it is a pretty clear distinction. Roll crimping is best used on the revolver cartridges, and taper crimping is the way to go for semi-automatic pistol cartridges. Here’s the why.

Cartridges designed for use in a revolver use some sort of a rim to properly headspace the case in the cylinder. Think .38 Special, .357 Magnum, .45 Colt, .44 Remington Magnum. This guaranteed headspacing allows the reloader to “roll” the case mouth around the cannelure of the bullet, ensuring that the bullet will not move during recoil. This also gives us a consistent overall length if you roll crimp on the cannelure.

I will note that a roll crimp should only be used with bullets that have a cannelure; if you try to roll crimp on a bullet without one, you risk bulging the case mouth, and it will not fit properly in the cylinder. We’ll get back to how to crimp a bullet with no cannelure for revolver use in a second.

The bullet seating die for most pistol cartridges can be adjusted to give a good, solid roll crimp. Read the die set instruction carefully, and follow the directions. It may take a few tries to get the proper crimp, and I usually make a dummy round, with no powder or primer, to use as a guide should the die come out of adjustment.

Those cartridges that work well in the semi-automatic pistols can’t be roll crimped, because those cartridges headspace on the case mouth rather than a rim, which most lack. You see, rimmed cartridges (generally speaking) don’t feed well from a pistol magazine, so the autoloaders usually employ a rimless design. Think .45 ACP, 9mm Luger, .40 S&W, .380 Automatic.

The rimless design needs to headspace on something other than the rim, of which there is none, and the lack of a shoulder (as in a rifle cartridge) leaves only the case mouth. If we were to roll crimp, we would compromise the squared case mouth for headspacing. Yet, we still need to hold the bullet firmly in the case.

40 Smith & Wesson ammo needs to be taper cripmed.

This is where the taper crimp method comes into play. It squeezes the sides of the case wall tightly against the bullet, and effectively prevents the bullet from moving, while maintaining the nice square case mouth that allows the cartridge to headspace.

A taper crimp can solve the problem I previously mentioned, where revolver cases use a bullet with no cannelure, yet need to be crimped. No bulged cases, no mess. Taper crimp and fire away!

Most companies that make quality reloading dies will have a taper crimp die available for purchase. If you’re serious about your pistol’s performance, I highly suggest you invest in one.

Stay crimpy, my friends.

 

Effects of Cartridge Over All Length (COAL) and Cartridge Base To Ogive (CBTO) – Part 1
Jul 1st, 2014 by RoundsReloaded

We found this article in the Berger Bullets website; it is an interesting and informative piece for reloaders seeking to improve accuracy. Remember that safety is achieved with knowledge.

 

Effects of Cartridge Over All Length (COAL) and Cartridge Base To Ogive (CBTO) – Part 1

Many shooters are not aware of the dramatic effects that bullet seating depth can have on the pressure and velocity generated by a rifle cartridge.  COAL is also a variable that can be used to fine tune accuracy.  It’s also an important consideration for rifles that need to feed rounds thru a magazine.  In this article, we’ll explore the various effects of COAL, and what choices a shooter can make to maximize the effectiveness of their hand loads.


Sporting Arms and Ammunition Manufacturers’ Institute (SAAMI)

Most loading manuals (including the Berger Manual), present loading data according to SAAMI (Sporting Arms and Ammunition Manufacturers’ Institute) standards.  SAAMI provides max pressure, COAL and many other specifications for commercial cartridges so that rifle makers, ammo makers, and hand loaders can standardize their products so they all work together.  As we’ll see later in this article, these SAAMI standards are in many cases outdated and can dramatically restrict the performance potential of a cartridge.

Bullet seating depth is an important variable in the accuracy equation.  In many cases, the SAAMI specified COAL is shorter than what a hand loader wants to load their rounds to for accuracy purposes.  In the case where a hand loader seats the bullets longer than SAAMI specified COAL, there are some internal ballistic effects that take place which are important to understand. 

 

Effects of Seating Depth / COAL on Pressure and Velocity

Figure 1. When the bullet is seated farther out of the case, there is more volume available for powder. This enables the cartridge to generate higher muzzle velocity with the same pressure.

Figure 1. When the bullet is seated farther out of the case, there is more volume available for powder. This enables the cartridge to generate higher muzzle velocity with the same pressure.

The primary effect of loading a cartridge long is that it leaves more internal volume inside the cartridge.  This extra internal volume has a well known effect; for a given powder charge, there will be less pressure and less velocity produced because of the extra empty space.  Another way to look at this is you have to use more powder to achieve the same pressure and velocity when the bullet is seated out long.  In fact, the extra powder you can add to a cartridge with the bullet seated long will allow you to achieve greater velocity at the same pressure than a cartridge with a bullet seated short.

When you think about it, it makes good sense. After all, when you seat the bullet out longer and leave more internal case volume for powder, you’re effectively making the cartridge into a bigger cartridge by increasing the size of the combustion chamber. Figure 1 illustrates the extra volume that’s available for powder when the bullet is seated out long.

Before concluding that it’s a good idea to start seating your bullets longer than SAAMI spec length, there are a few things to consider.

Geometry of a Chamber Throat

The chamber in a rifle will have a certain throat length which will dictate how long a bullet can be loaded. The throat is the forward portion of the chamber that has no rifling. The portion of the bullet’s bearing surface that projects out of the case occupies the throat (see Figure 2).

Figure 2. Chamber throat geometry showing the bullet jump to the rifling or lands.

Figure 2. Chamber throat geometry showing the bullet jump to the rifling or lands.

The length of the throat determines how much of the bullet can stick out of the case. When a cartridge is chambered and the bullet encounters the beginning of the rifling, known as the lands, it’s met with hard resistance. This COAL marks the maximum length that a bullet can be seated. When a bullet is seated out to contact the lands, its initial forward motion during ignition is immediately resisted by an engraving force.

Seating a bullet against the lands causes pressures to be elevated noticeably higher than if the bullet were seated just a few thousandths of an inch off the lands.

A very common practice in precision reloading is to establish the COAL for a bullet that’s seated to touch the lands. This is a reference length that the hand loader works from when searching for the optimal seating depth for precision. Many times, the best seating depth is with the bullet touching or very near the lands. However, in some rifles, the best seating depth might be 0.100″ or more off the lands. This is simply a variable the hand loader uses to tune the precision of a rifle.

Figure 3. Illustration of a bullet being seated out of the case too far to feed thru a magazine.

Figure 3. Illustration of a bullet being seated out of the case too far to feed thru a magazine.

Considerations for Magazine Feeding

When a hand loader is working to establish a seating depth to use with a particular bullet, he must decide if he needs the cartridges to feed thru a magazine or not.  If the shooting application is hunting or tactical shooting, then the shooter probably needs the rounds to cycle thru the magazine so the rifle can be used as a repeater.  However, in many slow fire target shooting applications, it’s not necessary to magazine feed the cartridges.

Often times when a shooter doesn’t need to feed rounds thru a magazine, the shooter can take advantage of substantial performance improvements by loading the bullets out long.  This brings up an important reality of seating depth and COAL.

 

SAAMI COAL Limits Ballistic Performance

It is a fact that the ballistic performance of modern ammunition is directly limited by the SAAMI COAL standards that are currently in place and that rifle manufacturers build to.  Even when a shooter understands the implications of cartridge case volume and has a chamber that allows them to load the rounds out long, the rifle itself (having been built to feed SAAMI length cartridges) won’t allow the shooter to do so.

This fact is one reason for the popularity of custom rifle builders who understand the importance of feeding longer than SAAMI length rounds and building rifles with long enough actions and magazines to cycle the rounds.  The first commercial rifle manufacturers who figure this out and start building rifles capable of feeding longer rounds will lead the way into modern times.  There have been many improvements to several key components of modern rifle ammunition, specifically bullets and powder.  It’s unfortunate that many rifle makers continue to adhere to the antiquated SAAMI limitations that were put in place so long ago when components were so different, standards which limit the performance of modern potential.

 Summary of COAL discussion

To recap the important considerations regarding bullet seating depth as it relates to COAL, we can say:

–  Seating a long bullet to the restrictive SAAMI COAL can severely decrease the internal volume of the cartridge which will limit the max velocity the cartridge can achieve.

–  If magazine feeding is not a requirement (or if you have a longer than standard magazine) you can load your bullets long, which increases the volume for powder and allows you to use more powder and achieve faster MV for the same pressure.

–  If you load the bullet too long and it encounters the lands, this can elevate pressure due to the engraving force resisting the bullets’ initial forward motion.

 

The second half of this article will discuss the differences between Cartridge Over All Length (COAL) and Cartridge Base To Ogive (CBTO), and why a working knowledge of both is beneficial to shooters and reloaders.

Bryan Litz

Case Trimmers, Cutting Your Brass Down to Size
Jun 23rd, 2014 by RoundsReloaded

Case Trimmers, Cutting Your Brass Down to Size

Using cases more than once means sooner or latter having to reduce their dimensions. That's when case trimmers such as this RCBS Universal Case Prep Trimmer comes into play.

In the reloading world, we are faced with a set of dimensional specifications that are prescribed by SAAMI (Sporting Arms and Ammunition Manufacturers’ Institute) and life goes much easier when we adhere to these dimensions.

The brass cartridge case that we use is the only component of the equation that is reusable, and that is because it is constructed of a malleable metal that can be resized and reshaped. Those very attributes of the brass cartridge case that make it a good choice for a reusable material see to it that we must trim that flowing, moldable material as it flows and stretches.

So, how do maintain these dimensions so that everything works well once we’ve reloaded our cartridges?

Well, there are a few tools that will make your life easier. The goal, simply stated, is to reduce our brass cases to a particular overall length, specific to each individual case. This overall length dimension is available in any good reloading manual, and you’ll need a micrometer to measure the cases. I like to trim my brass cases to the dimensions specified by SAAMI. This keeps things consistent with new brass.

You’ll need some sort of means of trimming the case, be it a hand cranked adjustable devise, or an electric motor driven machine. I use several different methods, some inexpensive (yet fully functional) and some on the expensive side of things.

Case trimmers can be as simple as this hand-operated model by Lee.

The Lee Case Trimmer uses a lock stud, shell holder, cutter and hardened length gauge; the length gauge is specific for each caliber. Depending on where you shop, you can get into this product for less than $15, and the tool can be used either by hand or chucked into a hand drill for quicker trimming. The length gauge has a pin which uses the flash hole as a guide and stops against the lock stud, so the cases are trimmed to a uniform and correct length every time. Although inexpensive, I’ve used this tool in many different calibers for decades.

Lyman, RCBS, and other companies make quality trimmers that utilize a hand crank to trim brass to length. Some are micrometer adjustable, and most come with caliber specific pilots that help hold the case in place to ensure a squarely trimmed case mouth. Once you set the depth to the desired length, all it takes is a few turns of the crank and your case is trimmed to length. The hardened steel cutters give a lifetime of service.

The Trim-It case trimmer is another neat little gadget that can deliver very accurate results. This trimmer works with a cordless drill or drill press to quickly and efficiently trim your brass. It is fully micrometer adjustable (each notch represents approximately 0.002”), and uses the case shoulder for support. The unit uses case specific dies that can quickly be mounted within the body.

My favorite tool, by far, is the RCBS Universal Case Prep Station. It is an electric motor driven trimmer (no more blisters!) unit, with adjustable rpm dial, and caliber specific collets. The length is micrometer adjustable, and the spring loaded jaws hold almost all rim sizes (although I found today that the big 50/90 Sharps is too big).

When using a case trimmer the micrometer becomes your best friend.

Hands free trimming is a wonderful thing, and the consistency is pretty solid, within 0.002” or so. Another nice feature of this machine is the six rotating heads on the top, which hold chamfer and deburring tools, as well as large and small primer pocket cleaning brushes. Sure saves the fingers and wrists!

Some manuals recommend trimming the cases to a dimension 0.010” shorter than the SAAMI specification. This is fine if you choose, yet not necessary. If you do choose to adhere to the shorter dimension, just remember to trim any new, unfired brass before you load it, to keep things consistent.

 

The stuck case blues
Jun 21st, 2014 by RoundsReloaded

THE STUCK CASE BLUES

June 13, 2014
stuck72
Sticking a case in the sizer die is a rite of passage for the beginning handloader. If you haven’t done it yet, that’s great, but it probably will eventually happen. When it does, fixing the problem requires a bit of ingenuity or a nice little kit like the one we got from RCBS.

 

decapstem72The first step is to clear the de-capping pin from the flash hole. Just unscrew the de-capping assembly to move it as far as possible from the primer pocket and flash hole. Don’t try to pull it all the way out. It won’t come. Just unscrew it and open as much space as possible inside the case.

 

drilling72Place the die upside down in the padded jaws of a vise and clamp it firmly into place. Using the supplied #7 bit, drill through the primer pocket. Be careful not to go too deeply inside the cartridge once the hole has opened up. It is important to be aware that the de-capping pin and expander ball are still in there and can be damaged by the bit.

 

 

 

 

 

 

 

taping72Once the cartridge head has been drilled, a ¼ – 20 is tap is used to cut threads into the pocket. Brass is relatively soft compared to a hardened tap, so no lube is needed for the tapping process. RCBS says that a drill can be used for this step, but it seems like a bit of overkill in a project of this nature. A wrench makes short work of the project.

 

RCBS supplies a part they call the “Stuck Case Remover Body” for the next step. If you are a do-it-yourselfer and have the bit and tap, this piece is easily replicated by a length of electrical conduit of the proper diameter and some washers. In either case, this tool provides a standoff for the screw that will do the actual pulling.

fingers72

 

 

 

 

 

pulling72Run the screw through the standoff and into the tapped case head. With a wrench, tighten the screw which hopefully pulls the case free. Once the case is free, clamp the case in vice and pull it free of the de-capping pin. There is tension here because the sizing ball is oversized to the neck dimension as part of the sizing process. It doesn’t take much force, but be aware there is still this last little hurdle to clear before you get back to loading.  Don’t feel bad, everyone does this.  Just use more lube next time.unstuck72

 

 

 

 

wholekit72

Introducing IMR® 8208 XBR super powder
Jun 15th, 2014 by RoundsReloaded

At times is good to resurrect old articles and products, especially in the face of the powder situation we are traversing right now; to that effect, we thought to bring back this news release from January 2010 from  IMR when the IMR 8208 XBR Super Powder was introduced.

Introducing IMR® 8208 XBR super powder

January, 2010

For Immediate Release

Shawnee Mission Kansas– IMR® Legendary Powders introduces a new super powder, IMR 8208 XBR.IMR 8208 XBR where no target is too small is a remarkably advanced technology propellant perfected for the greatest match, varmint and sniper rounds known today—223 Remington/ 5.56mm, 308 Win./7.62 mm, 6mm PPC, 204 Ruger, 6mm BR, 22-250 Remington and similar calibers.

This short grain extruded rifle powder exhibits a previously unheard of consistency with virtually no change in velocity at temperatures ranging from -40 degrees F to 165+ degrees F. Uniformity from shot to shot translates into tack driving accuracy and this powder has passed the test:

  • Currently loaded in premium factory sniper type ammunition
  • Leading competitive bench rest shooter Mr. Lou Murdica won numerous matches with it in 2009, starting with Heavy Varmint Grand Aggregate at the Cactus Classic
  • August 2009 Mr. Jim Carmichel won the International Benchrest Shooters Association’s 40th Group National Championships, Heavy Varmint Grand Aggregate. Because temperature conditions change, bench rest shooters vary charge weights during a day’s competition.  What is significant here is that Jim shot the exact same load of IMR 8208 XBR both days to win the event.

IMR 8208 XBR are available in 1lb canisters and 8lb kegs at dealers everywhere.  For more information or complete data visit imrpowder.com and the Reloading Data Center, see the 2010 Annual Manual, phone IMR at 913-362-9455 or write to 6231 Robinson, Shawnee Mission, KS 66202.

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