Posted on 10/16/2001 11:19:38 PM PDT by Don Myers
This is a vanity post. Many of us have different types of firearms. But what do we really know about the effectiveness of various ammunition? There are diffent types of bullets, the part of the cartridge that comes out of the barrel to make sure we have the terminology right.
For instance, the 7.62 X 39 comes in Full Metal Jacket, Hollowpoint, softpoint, and Armor Piercing. How does each one compare in stopping power with themselves and other rounds?
The .45 comes in FMJ and various hollowpoints. How do they compare in stopping power with the .40 S&W round?
If anyone would like to answer these questions, please feel free. I would like to know.
For reasonable comparison of the relative power of different cartridges, use the standard physics equation for the energy of a projectile: E = 1/2 mv^2, where E is kinetic energy, m is the mass of the projectile and v is its velocity.
For instance, to compare the 7.62x39 with the .308 (both of which are nominally 30 caliber), you need to know the weights of the projectiles and their muzzle velocities.
The standar 7.62x39 cartridge propels a 115-grain bullet at approximately 2300 fps at the muzzle.
A standard .308 cartridge propels a 148-grain bullet at a approximately 2800 fps at the muzzle.
Disregarding units, we can plug this ballistic data into the E = 1/2 mv^2 equation for relative powers of the rounds:
7.62x39: E = 1/2 x (115) x (2300) x (2300) = 304175000
.308: E = 1/2 x (148) x (2800) x (2800) = 580160000
Dividing 304175000 by 580160000 = .524, meaning that the 7.62x39 round is 52% as powerful as the .308 at the muzzle.
Mike, I might get a lot of hits if I did.
What they really need to do is make safer Surgeon Generals.
I own and have shot some of both. It seems to shoot just fine. You have to know if the particular ammo uses Berdan or Boxer primers - Berdan is corrosive, and you must clean the barrel with soap and water after shooting it.
One thing to keep in mind is that gunpowder, like all chemical compounds, is reactive and degrades over time. In other words, ammo is a perishable, though it perishes over a period of years or decades. I saw some data a few years back on a surplus ammo distributor's website where they chronographed ammo from the same batch for a period of years. Each year the average muzzle velocity dropped by an appreciable percentage. Ten year old ammo had lost considerable (twenty or thirty percent if memory serves me) muzzle velocity.
The only way to really judge the quality of surplus ammo is to chronograph it.
"Wednesday - Oct. 17, 2001 Program of the House of Representatives meets at 10:00 a.m.
"A motion to go to conference on the National Defense Authoriztion Act for FY 2002, H.R.2586 is expected."
Hope everybody contacted their respective Representatives during the past week and a half.
That is a little scary. Is that figure correct, anyone?
WWW Homepage: http://hitach.com EMail: hitach@hitach.com
Almost all of the Assault Rifle Ammunition being sold in the U.S. is surplus. The average Assault Rifle owner is usually satisfied to use this ammunition at the firing range. Much of this ammunition can be up to 30 or 40 years old and you have know way of knowing about it. Ammunition is usually not sold with dating! This can present a potentially serious and dangerous problem. Hitach sells primarily new or recently manufactured ammunition. Dating is guaranteed on everything that we sell, including surplus. We also indentify the place of manufacture. In most cases most suppliers are unable to provide this information about the ammunition that they are selling. It is important for you to know this information and how it effects you.
New Ammunition
The word new is meant to mean of recent production and for immediate sale. Many American and European firms are manufacturing NEW ammunition. A very limited number of rounds are available. They are more expensive and usually do not meet the same ballistic standards of comparable military assault rifle ammunition. The only source of 7.62x39mm Assault Rile Hollow Point (HP) is Russian. There is no other assault HP. The Russians are shipping massive quantities of hunting ammo. The former Eastern Block Countries are dumping very old surplus ammo in Full Metal Jacket (FMJ) and Soft Point (SP). Much the same thing is occuring in other military calibers. Why? Because they as well, as our own sources, know that the day of the ban on imported assault ammunition is close at hand.
The average person doesn't find out about these things before they happen. Then when they do occur, the price goes through the roof. The recent 1998 ban on all imported assault rifles is just such an example. There is more at stake than just price, which is dear to us all. If you want to guarantee your right to own this ammunition you need to act now. This means owning a cache of your favorite ammo. It also means you need new ammunition, because all ammunition breaks down with time. If you have a cache now don't shoot it. Use FMJ Target Training Ammo (AKA "Gallery Ammunition") or recent production FMJ. Save the best for last and you get a bonus - It's Cheaper!
Surplus Ammunition
Most Important surpus ammunition is still packed in its original box, tin or crate. When manufacturing for export to a specific country, the port of entry or city along with the date may be in a language of the importing country. Those of you who have bought Russian Hollow Point in 7.62x39mm manufactured for distribution in the U.S. may have noticed this on some of the cases. This also explains why so many cases can not be dated. If the Tula plant, in Russia, exports ammunition to a country other than the U.S. it will be in the language of that country. When that country decides to dump its surplus it sends it to the U.S. This is why people who speak Russian can not read the dating. It is in a different language! What does that tell you? If you can't read anything in English you have third hand surplus with no idea of when the stuff was made. It could be 50 years old and you would have no way of knowing it! This is important for many reasons.
The simple fact is that all ammunition breaks down with time. The rate of decay is proportional to the powder, primer and case used in the round and the method used to store it. Extremes of temperature and humidity are contributing factors. The effects can be measured in loss of velocity (which decreases trauma impact), in misfires due to bad primers, or even pre-detenation in extremely rare cases. The results of such an occurance are obvious.
Misfires - Primers
Misfires may be caused by a degradation of primers. Our testing confirms that misfires are directly proportional to age. Misfires are dangerous for 2 reasons.
The first is, if you are using your weapon for self-defense, the time it takes for you to resolve the misfire could or would enable your opponent to win in a firefight.
Second, the round may detonate from 5 to 60 seconds after being struck by the firing pin. If you have negligently cleared the round it could go off and cause serious bodily injury and death, either at the firing range or during self-defense.
Loss of Velocity
The average person does not have a background in ballistics. Most people think a bullet is a bullet. This is far from the case. The velocity, weight of the bullet, design, its ballistic co-efficient, and length of the barrel all determine the effectiveness of the round. Of all of these the velocity may be considered to be one of the most important because a loss in velocity results in a loss of Trauma to the Body. Trauma is what determins the real outcome in a fire fight.
This seldom results in a favorable reaction. To test this hypothesis we randomly sampled 7.62x39mm Surplus Ammunition from 1958, 1969, 1972, 1985, 1993 and 1996. Twelve rounds out of every 120, in cases of 1440 rounds, were test fired and chronographed. That is 144 rounds per case. There were problems in conducting the research. Although we were able to determine the date of manufacture, we could not determine what type powder or primer was used. It would take serious laboratory testing to make such a determination. We felt that it would make little difference in the research because the net results should be about the same. The true velocity of most of these rounds should have been about 2400 ft/sec.
Our results follow:
Velocity Chart
Date Low ft / sec. Lot Average ft / sec. Lot High Ft / sec. Lot
1958 1222 1297 1381 1964 1485 1560 1623 1969 1501 1644 1787 1972 1671 1800 1910 1978 1788 2005 2190 1985 1956 2109 2234 1991 2203 2280 2309 1993 2310 2344 2379 1995 2375 2398 2424 1996 2235 2402 2463
Misfires were calculated in three groups, with 432 rounds in each group. In the group 58, 64, and 69 there were 18 misfires or 4.2%. In the group 72, 78 and 79, there were 10 misfires or 2.3%. In the group 91, 93 and 1996, there were 2 misfires or 0.46%.
The high deviation in the earlier years is unacceptable for target practice, personal defense or hunting purposes. This makes these rounds unacceptable for practical use.
Most people buy their ammunition in individual boxes. The average sale is about 1 to 5 boxes at a time. Annual average purchases could be as high as 1000 rounds or more. The Date of the Manufacture, Velocity, and Energy, are not reflected on the ammo box so you have no idea what you are buying. The velocity, of a bullet has the most impact on the trajectory of any given bullet. As a general statement, the higher the velocity the flatter is the trajectory. In other words, the drop of the bullet is lessened as a function of range with higher velocity. Conversly, the lower the velocity the faster a bullet drops. If you bought some surplus 7.62x38mm manufactured in 1958, some from 1972 and some new ammunition it would all shoot very differently. This is one of the reasons why so many AK47, SKS and other 7.62x39mm shooters who excel with bolt action rifles can not maintain consistency with their assault rifles. This defeats your whole purpose because you are using ammunition that is not consistent. If all your ammunition is purchased at the same time and from the same lot, the performance characteristics will be the same. This explains why so many odd lot buyers have the unfounded belief that AK and SKS based rifles are less accurate. No two boxes from different batches will shoot alike.
Ammunition cached in the 1950's through the late 1980's makes up the bulk of the surplus being sold. It is a pretty fair assumption that you are buying ammunition with substantially lower rated velocity, energy, and with a higher than normal misfire rate. Ammunition manufactured after 1994 compares favorably with the new ammunition. The same may be said for Chinese and ex-soviet block countries. The New Russian Tula Works 122grain HP with non-mercuric primers is the best 7.62x39mm military ammo in the world. It is manufactured using modern technology to cache longer than anything before it.
Ask your ammunition supplier, if he can tell you where and when the Russian ammunition he is selling you was manufactured? Ask him what the Velocity should be? The chances are they will not be able to answer your questions. That's why some surplus ammo is selling for between $3.00 and $5.00 a box. It's simple, you get what you pay for. At Hitach we try to give you as many options as we can. We tell you the truth straight out because it is all we do. We really do care.
Light Loads Gallery Ammunition
Most shooters have never heard of Ligh Loads or Gallery Ammunition. These are the rounds that shoot a lighter bullet with less power. The recoil in Gallery Ammunition for a 7.62x39mm FMJ is only 500 ft/lbs. The standard HP has 1500 ft/lbs. The recoil in Gallery Ammo is roughly equivalent to a .38 special. It is used to train military personnel. Why? Because Gallery ammo does not beat you up. You can fire the stuff all day without a bruise or sore muscles. When you go target shooting it is what you should be using. But that is not the point in this message.
All Gallery ammunition is FMJ. If you never see the ammo case, in English, or the person selling it to you does not know what it is, the conclusion drawn will be that it is regular FMJ. In these cases you will be paying more for less and if you had to defend yourself with it you would be doing so at 1/3rd the terminal energy. That is not to say Gallery ammo isn't powerful. At 100 yards it's equal to a .38 at the muzzle and that's nothing to sneeze at. The problem is you are not getting what you are paying for.
Practical Considerations
The vast majority of people, who own semi automatic assault rifles, either buy their ammunition from the local gun shop, by mail order, or at gun shows. The pattern also includes buying from different batches as well as sources. As you have seen each is fraught with different problems.
Almost every major American or European commercial manufacturer loads ammo for most military semi automatic assault rifles. You can buy .223, .308 and 7.62mm at any gun shop. Look at the price! While you're at it look at the selection. It is very limited. In many cases only one or two different rounds will be in stock for each. It gets worse! Most, but not all, NEW commercial ammunition is loaded to a lower velocity and subsequently lower terminal energy. What you are faced with is a small selection of high priced ammunition that is not equal of Government Issue. This is not a reasonable solution. The only real round out there to match this performance was Winchester's U.S. Government Whte Box. It is beyond doubt the best FMJ ever made. Winchester no longer makes it. We bought every box we could find and still have it in stock.
The other approach is mail order or gun shows. With mail order you really never know what you are going to get. We even get stuck once in a while. If the price is cheap you can bet all the money you are going to spend that it's junk. As to Gun Shows, we have told you how to read the case. If you can read a port or city name in English the date will usually be on the case, that is [10/96]. This says it was manufactured for the U.S. Market in October of 1996. If you can not read it, it is probably quite old and third hand.
IS IT ILLOGICAL TO PAY MORE FOR LESS OR LESS FOR LESSER ?
The Solution:
The solution is to purchase your ammunition from companies who specialize in military semi automatic based weapons. HITACH INDUSTRIES specializes in this industry and is, in total, the only company of its kind. HITACH searches the world for quality new military ammunition. The company offers some new commercial ammunition, which is note worthy for a particular application. Surplus is offered as surplus with one major difference. We test fire each batch for quality control and will not offer anything for sale that does not meet the company's high standards. We have over 6,000,000 items in our data base and have 75 different sources to help us locate just about anything you can imagine. Hitach took over Sandyco's Custom Loading technology for use in military calibers. Before this Web Site was written our production was sold out. We are on a 90 days to 6 months backorder. Whatever you need we are here for you.
Copyright 1998 Hitach Industries, Inc.
Full Metal Jacket and Armor Piercing...same shape. delivers less energy to the target, tends to go right through soft targets. AP to punch through armour.
Hollow points are spires with a very small hollow at the tip, they have the highest BC and thus allow the best accuracy. They can deliver more energy to the target if that's what they were designed for, else they are like FMJ.
Soft points are expanding bullets that deliver the most energy to soft targets. Unlike the 30-30, the 7.62X39 can use high BC spire points giving them much more freedom from the effects of drag and wind.
i remember when jocelyn elders went to a benefit concert by eric clapton. after the concert she said, 'hey, i like eric CLAPNER'! rush had a ball with that one.
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