Self Defense Ammunition and Caliber Information

M34 Tactical

Self Defense Ammunition and Caliber Information

5.56 VS .223 Ammunition and Chamber Dimensions

The .223 Remington is a sporting cartridge with the same external dimensions as the 5.56x45mm NATO military cartridge. It is loaded with a .224" diameter, jacketed bullet, with weights ranging from 40 up to 90 grains, though the most common loadings by far are 55 grains.

The primary difference between .223 Remington and 5.56 x 45 mm is that .223 is loaded to lower pressures and velocities compared to 5.56 mm. .223 Remington ammunition can be safely fired in a 5.56 mm chambered gun, but the reverse can be an unsafe combination. The additional pressure created by 5.56 mm ammo will frequently cause over-pressure problems such as difficult extraction, flowing brass, or popped primers, but in extreme cases, could damage or destroy the rifle. Chambers cut to .223 Remington specifications have a shorter leade (throat) area as well as slightly shorter headspace dimensions compared to 5.56 mm "military" chamber specs, which contributes to the pressure issues.

While the 5.56 mm and .223 cartridges are very similar, they are not identical. Military cases are made from thicker brass than commercial cases, which reduces the powder capacity (an important consideration for handloaders), and the NATO specification allows a higher chamber pressure. Test barrels made for 5.56mm NATO measure chamber pressure at the case mouth, as opposed to the SAAMI location. This difference accounts for upwards of 20,000+ psi difference in pressure measurements. That means that advertised pressure of 58,000 psi for 5.56mm NATO, is around 78,000 psi tested in .223 Rem test barrels (SAAMI .223 Rem Proof MAP is 78,500 psi so every 5.56mm round fired is a proof load, very dangerous). The 5.56 mm chambering, known as a NATO or mil-spec chambers, have a longer leade, which is the distance between the mouth of the cartridge and the point at which the rifling engages the bullet. The .223 chambering, known as the "SAAMI chamber", is allowed to have a shorter leade, and is only required to be proof tested to the lower SAAMI chamber pressure. To address these issues, various proprietary chambers exist, such as the Wylde chamber[2] or the Armalite chamber, which are designed to handle both 5.56 mm and .223 equally well.

Using commercial .223 cartridges in a 5.56-chambered rifle should work reliably, but generally will not be as accurate as when fired from a .223-chambered gun due to the excessive leade. [3] Using 5.56 mil-spec cartridges (such as the M855) in a .223-chambered rifle can lead to excessive wear and stress on the rifle and even be unsafe, and the SAAMI recommends against the practice.[4] Some commercial rifles marked as ".223 Remington" are in fact suited for 5.56 mm, such as many commercial AR-15 variants and the Ruger Mini-14, but the manufacturer should always be consulted to verify that this is acceptable before attempting it, and signs of excessive pressure (such as flattening or gas staining of the primers) should be looked for in the initial testing with 5.56 mm ammunition.

Choosing the Best Caliber for Self-Defense
By Jorge Amselle

As an NRA instructor, I always enjoy teaching beginners. I typically get a lot of couples and families who sign up for beginners classes. Invariably, the question always comes up, “what is the best gun,” or “what is the best caliber?” Of course, the answer is “it depends.” That’s like asking, what is the best mode of transportation?

These first-time shooters are actually asking a very good question and with good reason. In the case of a couple or a family, the primary concern is most often personal protection inside the home. That is not difficult to address since the rule of thumb is generally to use the largest caliber gun you can comfortably handle.

When routine concealed carry is not a primary concern, then the size of the gun is less of an issue. Basic physics teaches us that force (the amount of energy a bullet carries when fired) is the result of the mass of an object (the weight of the bullet) multiplied by the acceleration (speed in feet per second of the bullet). Here is an easy-to-use online kinetic energy calculator that provides the ft.-lbs. of energy for a particular cartridge as long as you know the weight of the bullet and its velocity.

The more force a bullet has, the harder it hits, the more it penetrates and the more it transfers force—all good and necessary for personal protection. However, the second rule of Newtonian physics teaches us that for every action there is an equal and opposite reaction. In other words, the more force a bullet has going forward the more force the gun has going backward (recoil).

The more mass a gun has, the less acceleration (perceived recoil) a particular cartridge will produce. So, in home defense, a full-size gun helps recoil-sensitive shooters handle more powerful calibers with a higher level of comfort and accuracy.

The second concern is the catch, however. Guns constitute a significant expense for many people, and in these tough times, a family may not be able to or be interested in purchasing different guns for each family member. One gun in one caliber may often have to fit the needs of everyone in the household.

Focusing on just the most popular personal-protection calibers, presented here are some of their differences and their relative strengths.

Special Note: What about the .22 LR, +P ammunition and expanding bullets? The .22 Long Rifle, or .22 LR, cartridge is everywhere. It is super cheap, fun and easy to shoot with almost no recoil. However, while it is perfectly lethal, and any gun is better than no gun, it does not produce enough energy to reliably stop a threat in short order and is not considered suitable for self-defense. It is, however, excellent for target practice, and if more than one gun is in your budget, a .22 for training would make a good choice.

Most ammunition manufacturers sell cartridges in all calibers designed specifically for personal protection. These are intended to provide the maximum energy for a given cartridge and use bullets that will produce the most effective terminal performance. Ammunition can be found in standard pressure varieties as well as +P or +P+, which produce higher-than-standard pressure and velocity. This higher-pressure ammunition should only be used in guns rated to handle the extra forces, and it will produce more recoil.

Likewise, the shape and weight of the bullet affects both terminal energy and performance. A heavier bullet carries more force but is slower, and velocity has a much higher multiplier effect on force than does mass. Most self-defense ammunition is designed to expand on impact in order to have the maximum effect on the target. It is for this reason that different types of expanding ammunition are so popular with law enforcement, as well as those interested in personal protection.

.38 Spl.: This cartridge is considered by many experts to be the minimum necessary for adequate personal protection, along with the .380 ACP listed below. For decades, this was the standard round for law enforcement and it served well, even using the plain round-nose lead ammunition. Anyone who chooses this soft-kicking cartridge today will be even better served thanks to the availability of specialized self-defense ammunition.

.357 Mag.: As the name implies, this is a powerful cartridge with a reputation for producing one shot stops against two-legged predators. That power runs both ways and it can be tough to handle for some. One notable benefit here is that, since this is just a .38 Spl. with a slightly longer case and a lot more power, revolvers cambered for .357 Mag. can be loaded with .38 Spl. for recoil-sensitive family members. The reverse, however, does not apply.

.380 ACP: Long popular for small semi-auto pistols in Europe and countries where possession of military calibers is restricted, the .380 ACP (or 9 mm Short) cartridge has taken America by storm in the last few years. This is thanks to the increased popularity of concealed carry and the ability of this cartridge to fit very small guns. Much like the .38 Spl. above, it is considered a minimum self-defense cartridge, but was used for decades by European police officers and, most famously, by James Bond.

9 mm: Consider the perennial European cartridge, the 9 mm is fast, straight shooting, light kicking, easy to find and cheap to shoot. It is equally at home in full-size guns as in small concealed-carry ones. It is for these reasons that it is in such widespread use among modern law enforcement agencies and militaries (including ours) worldwide. It is more than sufficiently powerful enough for self-defense with proper ammunition and easy for beginners to master.

.40 S&W: Is it better to have big, powerful rounds or more of them? This is America, so why not both? The .40 S&W cartridge is a less-powerful version of the 10 mm, and it offers heavy bullets with a lot of velocity, while remaining comfortable for most to fire with magazine capacity that is close to that of a similar-sized 9 mm pistol. The .40 S&W is a favorite among many law enforcement agencies and individuals focused on self-defense, and for good reason.

.45 ACP: This is the American cartridge: big, loud and powerful. Nearly half an inch in diameter, hollow-point ammunition resembles a flying ashtray as much as a bullet can. This heavy, slow-moving cartridge was the standard for the U.S. military for over 70 years and served on every battlefield (and still does) where Americans have fought. While it has stout recoil, it feels more like a push that a jab, and with practice, it is manageable by most and preferred by many.

In the end, the key is to get out to the range and try out a variety of guns and calibers to find the one you like best. Just like buying a car, if you are only getting one to share, it is always best to test drive it and make it a family decision.

Best Choices for Self Defense Ammo

Choosing The Best Caliber For Concealed Carry

Q: How long will my barrel last?

A: (with data from Bushmaster and LTC Santose)

The U.S. Army recently (Oct 2000) reported the Mean-Time-Between-Failures (MTBF) for M16A2/M4/M4A1 barrels is 9600 rounds. These are chrome lined barrels with a 1:7 twist made out of 4150 steel (just like Bushmaster & Colt use), and they see full-auto use. Also note the military is using full power M193 & M855 rounds, while most commercial .223 runs 100 to 200 fps slower (with the same bullet weight). The 1:7 twist barrels do burn out quicker than the 1:9, especially under full auto stresses. For a chrome lined barrel on a semi-auto only rifle 20,000 rounds (or more) can be expected. [Warning: More civilian barrels are ruined to over (or careless) cleaning than to being "shot out".] Stainless barrels won't last as long, 4140 steel barrels wear longer than stainless; but not as long as the Colt 4150 barrels (w/o the chrome lined bores). nor as long as the chrome lined bores (given the same shooting)."

"Grains"

During World War 2 smokeless gunpowder was named Cordite and it was made a little different than today. Today it is made from nitrocellulose and nitroglycerine. Try not to buy gun powder that is really old- some of the explosive components within the powder tend to dissipate in time.

The weight of a (lead) bullet as well as the weight of gunpowder is measured in grains in the United States and Canada. The grain in the year 1758 was the weight of a seed from the middle of an ear of barley. "Grains" is the smallest unit of weight in the English system. This method of measuring weight relied on the relationship between the number of grains of wheat that were equal to one pound. Gunpowder scales for hand loading measure in grains:
bullets are generally measured in increments of 1 grain,
gunpowder in increments of 0.1 grains.

A troy ounce is 480 grains, somewhat heavier than an avoirdupois ounce
(437.5 grains). A grain is exactly
64.798 91 mg; hence one troy ounce is exactly
31.1034768 g, about 10 percent more than the avoirdupois ounce, which is exactly
28.349523125 g. The troy ounce is the only ounce used in the pricing of precious metals, such as gold, platinum, and silver. The grain, which is identical in both the troy and avoirdupois systems, is used to measure arrow and arrowhead weights in archery and bullets and powder weights in shooting. In troy weight, there are 12 ounces in a pound, rather than 16 as in the more common avoirdupois system. The troy ounce may be abbreviated to ozt. In the normal pound (16 oz.) that is used now in the United States, there are 14.58 troy ounces.

12 ounces= 1 pound; or 5760 grains= 1 pound; or
373.241 721 6 grams= 1 pound; 15.43 grains= 1 gram

Bullet Weight and Powder chart

http://data.hodgdon.com/cartridge_load.asp

Bullet Acronyms:

AP — Armor Piercing (has a steel or other hard metal core)

ACC — Accelerator

BBWC — Bevel Base Wadcutter

BEB — Brass Enclosed Base

BT — Boat-Tail

BTHP — Boat Tail Hollow Point

CB — Cast Bullet

CL — Core-Lokt

DEWC — Double Ended Wadcutter

FMJ — Full Metal Jacket

FN — Flat Nose

FP — Flat Point

FST — Fail Safe Talon

GD — Gold Dot

GDHP — Gold Dot Hollow Point

GS — Golden Saber

HBWC — Hollow Base Wadcutter

HC — Hard Cast

HP — Hollow Point

HPJ — High Performance Jacketed

HS — Hydra Shok

J — Jacketed

JFP — Jacketed Flat Point

JHC — Jacketed Hollow Cavity

JHP — Jacketed Hollow Point

JSP — Jacketed Soft Point

L — Lead

L-T — Lead Combat

L-T — Lead Target

LFN — Long Flat Nose

LFP — Lead Flat Point

LHP — Lead Hollow Point

LRN — Lead Round Nose

LSWC — Lead Semi-Wadcutter

LSWC-GC — Lead Semi-Wadcutter Gas Checked

LWC — Lead WadCutter

LTC — Lead Truncated Cone

MC — Metal Cased

MRWC — Mid-Range Wadcutter

+P — Plus P (10-15% overpressure)

+P+ — Plus P Plus (20-25% overpressure)

PB — Lead Bullet

PB — Parabellum

PL — Power-Lokt

PSP — Plated Soft Point

PSP — Pointed Soft Point

RN — Round Nose

RNFP — Round Nose Flat Point

RNL — Round Nosed Lead

SJ — Semi Jacketed

SJHP — Semi Jacketed Hollow Point

SJSP — Semi-Jacketed Soft Point

SP — Soft Point

SP — Spire Point

SPTZ — Spitzer

ST — Silver Tip

STHP — Silver Tip Hollow Point

SWC — Semi Wadcutter

SX — Super Explosive

SXT — Supreme Expansion Talon

TC — Truncated Cone

TMJ — Total Metal Jacket

VLD — Very Low Drag

WC — Wadcutter

WLN — Wide Long Nose

WSM — Winchester Short Magnum

WSSM — Winchester Super Short Magnum

XTP — Extreme Terminal Performance

Slicing the Pie Maneuver

It is late at night and a noise coming from across the house rouses you from your sleep. Your wife wakes up too and whispers to you that she thinks someone is breaking in. Your heart rate increases dramatically while all the blood from your extremities rushes to your vital organs—triggering your fight or flight response. The adrenaline feels like a drug as your breathing increases and pupils dilate. You quickly regain control of your thoughts and tell your wife to run into the bathroom with the phone and lock the door. You quietly reach into your drawer and grab your .45 caliber handgun and your flashlight—time to go and see what’s what.

For most people, this scenario is one of the most dangerous things you will ever do. Slipping through your home in the middle of the night to confront an unknown threat is not only hazardous it’s potentially deadly. Some would argue that the best thing you can do in this situation is try to escape, or lock yourself away and wait for the police to eventually show up and write a report. While I have nothing but respect for the impossible job the police are burdened with, in most cases, they simply can’t get there fast enough. If you live in a rural area, it may take half an hour for a squad car to arrive in your driveway. It is my opinion that the best course of action is to clear the house yourself, and eliminate the threat. The burglar may only be there for your television, but they are going to have to get through you to take it. In most places in the United States, you have the right to protect your property without having the obligation to attempt to flee.

Unfortunately, the majority of people who buy a gun for home defense take it to the range once, and never really learn how shoot it. An even larger majority never learn how to fight with it. There is a lot more to gunfighting than just hitting a stationary target at 10 yards. When moving around a corner, deploy a basic maneuver call slicing the pie. The concept is simple, and it can save your life. The idea behind slicing the pie is that your target has minimal time to react to your presence before you get a chance to fire your weapon. To traverse a corner, simply do the following:

Approach the corner as close to the wall as you can get without rubbing up against the wall and making noise. Giving away your position is the last thing you want in this situation.

Put your eye on the corner and remember that the apex of the corner is your pivot point.

Take a horizontal step away from the wall. Keep your elbows close to your body and don’t let anything poke around the corner ahead of you.

Pause and scan the slice of the pie. Between each step taken, you should scan from the floor at the corner to the ceiling—scanning each slice in a vertical motion.

Lean slightly toward the direction you are stepping to allow your head and eyes to be the furthest object, allowing you to see your target before he sees you.

Shoot with either hand, if you can, using the hand closest to the direction you are moving.

Do not cross your feet, since this is not a very stable stance for shooting. Remember that you may have to fire your weapon at any moment.

Always point your firearm where your eyes are looking. This will allow you to react more quickly than if you have your firearm at low ready. Arms extended or high-compressed ready are both good options. With high-compressed ready, make sure that your non-firing hand is behind the plane of the muzzle.

This little maneuver is identical to the way police and military personnel traverse corners in tactical situations. Performing this act alone isn’t always the safest option, but if you have no other choice, you should at least do it correctly. This will increase your probability of survival, making you a more proficient gun owner. Exercising your right to protect your family is not only your right; it is your duty as a responsible citizen.
From http://cheaperthandirt.com/blog/?p=20986