Contents
Introduction
Evaluating a Barrel
Barrel Gauges and Measurements
Identifying Finish
Parkerizing
Blued Guns
"Greek Black"
Pitting and Corrosion:
Import Marks
Ammo: What kind is best?
Cleaning and Care
Seeing What You Buy in Action: Our test fire videos
Exploded Drawings
Fernwood Armory
©Fernwood Armory 2015
Introduction
Many of our customers are first time buyers when it comes to used military firearms. A quick Google search will turn up thousands of pages of information on these weapons. There are also forums, collectors’ groups and dozens of books devoted to the subject. It can be a bit overwhelming.
We put together this guide to address some of the more common questions we receive, including determining condition, identifying markings, even what kind of ammunition to use. This guide also explains how we select and prepare the guns we sell at Fernwood Armory. Our inventory typically includes the M1 Garand, M1 Carbine, Model 1903 and 1903-A3, and the Model 1911-A1. The information here is correct to the best of our knowledge. Some aspects of gun collecting and condition are subject to opinion. We hope this guide helps you to make an informed purchase, whether you buy from us or elsewhere.
Evaluating a Barrel
Most used military guns we sell are at least 60 years old. And with age comes a lot of potential problems, so close inspection of these guns both inside and out is essential. We'll start this guide with the barrel.
We evaluate barrels by visual inspection and with bore gauge measurements. (We include pictures of the bore and gauge measurements in the guns we list for sale, we will discuss those measurements in greater detail later on in this guide).
A bright bore light is needed to avoid unknowingly buying a gun with a corroded or damaged bore. Bore snakes are also handy, as bores of guns for sale can be dirty or dusty. We carry bore snakes with us in all buying situations. Little can be known about a bore’s condition when it is dirty.
Figure1/M1 Carbine bore, bright with sharp riflings. ©Fernwood Armory 2015
A new buyer should look down the bores of a few new barrels of various calibers to become familiar with their appearance. A new barrel’s bore should appear very bright, usually with almost a mirror-like shine, when inspecting it with a bore light. Sometimes a new bore shows tool marks, from the cutter that made the riflings.
We sometimes use the term “bright but used” for a bore that is bright but has lost a little of its shine due to age and minor wear. “Frosty” to us means that there has been minor corrosion, (like the bore shown below), but little enough that its discoloration will clean out, leaving metal color with a dull appearance.
Figure 2/M1 Garand bore, “frosty”©Fernwood Armory 2015
A frosty bore can shoot as well as the brightest, but may require more effort to get it clean after use. A “dark” bore is very corroded, may not be safe to shoot, and is definitely undesirable. Frosty and dark bores will not get better with use, in our experience.
Figure 3/Crown on M1 Garand ©Fernwood Armory 2015
The muzzle end or crown should also be checked for damage. The crown is the opening or hole in the front end of the barrel, or muzzle, where the bullet exits. Crown also refers to the overall shape of the end of the barrel, as there are not separate terms for the shape and the opening itself. The opening, the last part of the bore that the bullet touches, should be uniform around the bore circumference. If it is not, the high pressure gas escaping around the bullet as it exits the bore is not uniform, and can disturb the stability of the bullet, resulting in degradation of accuracy. The edge of the opening is usually fairly sharp, and therefore fragile. This opening is usually protected by the machining of various shapes around it.
Figure 4/Rounded Crown on M1 Carbine ©Fernwood Armory 2015
Figure 5/Flat Crown, M1 Carbine © Fernwood Armory 2015
An M1 carbine crown resembles a doughnut cut in half. A postwar M1 rifle crown is flat, but with a partial cone on the outside and a partial inverted cone on the inside. Some non-military target crowns consist entirely of a shallow inverted cone. Many other shapes are used. Impact damage to the outside of the barrel end is not necessarily a problem if it does not affect the escaping gas around the bullet as it exits the bore. A shaped crown is not necessary; a perfectly flat crown will work as well as any, but the edge of the opening is less protected.
Barrel Gauges and Measurements
In our military rifle listings you will see the terms TE and ME (or MW), along with pictures of gauges like the ones shown below. These measurements are relative indications of a used barrel’s bore condition.
Figure 6/Muzzle Wear Gauge ©Fernwood Armory 2015
Figure 7/Throat Erosion Gauge ©Fernwood Armory 2015
The muzzle and throat readings are easy to make, with the appropriate gauges, and usually do not require disassembly of the rifle. Lower numbers generally indicate closer to new condition. A barrel with low gauge numbers is probably more accurate than one with high numbers, but shooting it is the only real accuracy test. A barrel with lower gauge numbers is probably capable of more shooting before becoming worn to an inaccurate condition, although significant wear is the result of thousands of rounds. The measurements may affect the value of a rifle, whether for shooting or collector purposes.
Many enthusiasts profess that bore measurements work like this:
- New barrel, will put all bullets through the same hole, ME 0, TE 0
- Worn out barrel, won’t put two bullets in the same time zone, ME 3, TE 5
Of course this isn’t the case, but we are aware of popular opinion, and seldom offer rifles for sale with gauge numbers any higher. To be fair, ME 3 and TE 5 are less than ideal, and combined with visual inspection, may be good reason to consider replacement, if very accurate target shooting is the goal. However, a barrel with these measurements may perform quite well.
We use MW gauges on M1 carbine barrels, but are not aware of any “official” TE gauges for the carbine. There are some carbine TE gauges with unnumbered scales that can be used to compare throats of carbines to themselves as they age, or to other carbines.
Theoretically, a new .30 caliber barrel has a bore diameter of exactly 0.300”, and every chamber is cut exactly the same. This would result in gauge measurements of 0 TE (throat erosion) and 0 MW (muzzle wear). If thousands of rounds are fired through the barrel, the bore will wear to a slightly larger diameter, such as 0.303”. If the bore diameter becomes large enough due to wear, accuracy will decrease. Experts do not agree on which measurement, TE or MW, is most relevant to accuracy. The TE measurement of a new barrel can be affected by its installation in a rifle receiver.
MW or muzzle wear is a measurement of the bore diameter at the front or muzzle. The MW gauge is slightly tapered, so it goes further into a worn barrel than a new one. A measurement of 0 corresponds to .300”, a measurement of 1 to .301”, 2 to .302” etc. We have measured new-in-the-wrap GI barrels with MW measurements from 0 (0.300”) to 1 (0.301”). So, MW up to 1 may not mean that a barrel has had any use at all. MW of 2-3 indicates a used but possibly very good barrel.
Figure 8/Muzzle gauge in M1 Garand ©Fernwood Armory 2015
How much MW is too much? Opinions vary is an understatement. The best full clip M1 group we have ever fired happened to be from a barrel with MW of >3, considered by some to be hopelessly worn.
However, MW more than 3 usually indicates fairly serious wear, and that >3 barrel would not stand up to as many future rounds as a new barrel.
Figure 9/Throat Erosion gauge in M1 Garand ©Fernwood Armory 2015
TE or throat erosion is a measurement of the diameter of the riflings at the specific point where they are supposed to begin (leade) at the front of the chamber. The TE gauge has a tapered section at the front, and the scale at the back indicates the rifling diameter at the reference point. The measurement is the scale indication that lines up with the back end of the barrel. TE 0 means that the rifling diameter is 0.300” at the reference point/leade. TE 5 indicates that the rifling diameter is 0.305”, or that the throat has eroded 0.005 from new. However, we have measured TE up to 2 on newly installed, new M1 barrels. A barrel that measures TE up to 2 with low MW may very well be in new condition, because the finish reamer actually cuts the leade, the reference point for TE measurements, at a specific distance from the bolt face, which may not be exactly aligned with the back edge of the barrel. TE of a newly installed barrel can measure high because it is not practical to measure from the bolt face to the leade.
Our best full clip M1 group ever, mentioned above, was with a barrel that measured MW >3 and TE 5. We shot more groups to make sure we hadn’t “got lucky”. The combination of barrel, ammunition, and the many other factors that affect accuracy can result in significant variations between individual rifles with any barrel condition.
Some experimenters have deliberately shot thousands of rounds through one barrel to find out how many it takes to wear one out. In one test, the barrel was still performing quite well at 13,000 rounds (MW 7) and didn’t become noticeably inaccurate until 14,000 rounds (MW 8). The barrel was still hitting the target, but fewer hits were toward the center. MW was approaching 3 at the time. If you require a barrel that will withstand 14,000 rounds before becoming somewhat inaccurate, then you must find one with 0 gauge measurements.
The same experimenters also tested a near-universal belief that MW is caused by cleaning rods. Using the jointed GI cleaning rods believed to be the most damaging, they put many thousands of cleaning strokes into a single barrel, applying side force in an effort to deliberately cause MW.After 60,000 hard strokes, and wearing out and breaking several rods, the MW was increased by a single increment. It seems more likely that most MW is caused by the hot gas created by the burning gunpowder. When the bullet leaves the barrel, the pressurized hot gas is suddenly allowed to escape and accelerate between the crown and the bullet base,eroding the forward end of the bore. Hot gas is considered to be the cause of throat erosion, so a similar effect, less severe due to somewhat lower pressure and temperature, is not surprising at the muzzle. Generally, MW of a used barrel measures a number or two lower than the TE.
Identifying Finish
How can you tell if a particular firearm has its original parkerized finish or has been refinished? This can be a very important question for “collector” guns. It is impossible to be absolutely, 100% certain that a particular gun has its original finish unless it can be proven, such as examples in factory museums that have never left the premises. However, experienced collectors can provide nearly 100% opinions based on the observation of many guns over time.
Figure 10/Original parkerized finish, M1 Garand ©Fernwood Armory 2015
Indications that a gun may have its original parkerized finish include:
- very smooth exposed metal surfaces (as opposed to the sandblasted appearance of many reparkerized guns);
- a reasonable amount of wear commensurate with the gun’s age;
- sometimes a greenish color associated with long term exposure to Cosmolene, very difficult to duplicate;
- stamped markings or lettering known to have been applied after finish at the factory.
Figure 11/Reparkerized receiver, 1903-A3 ©Fernwood Armory 2015
Some guns are quite obviously refinished. Indications of refinished or reparkerized guns include:
- a very uniform rough and dry appearance;
- every metal part is exactly the same color including parts that should be blued;
- lettering and serial numbers eroded; parkerizing over pitting/rust or dents/gouges.
Parkerizing
Many U.S. military firearms were originally parkerized, including the M1 carbine, M1 rifle (Garand), M1903A3, and M1911A1. Firearms can also be refinished using the parkerizing process. Parkerizing is a method of protecting a steel surface from corrosion and increasing its resistance to wear through the application of a chemical phosphate conversion coating.
Figure 12/HRA M1 Garand parkerized ©Fernwood Armory 2015
The color of a parkerized finish varies greatly, due to the different chemicals that can be used and variations in preparation and application methods. The colorof an individual parkerized gun or partmay change over time. A parkerized surface must be covered with oil for maximum corrosion protection.
Figure 13/Reparkerized M1 Carbine Parts (except for magazine) ©Fernwood Armory 2015
Blued Guns
Parkerizing usually has a very different appearance than bluing. Blued guns are generally polished and a very dark color, while parkerized guns usually have a matte appearance (unless the parkerizing is worn) of varying color. Some WWI military guns were originally blued, or finished with a process that looks much like bluing.
Figure 14/Blued bolt, parkerized M1 carbine receiver ©Fernwood Armory 2015
Figure 15/1911A1: Parkerized with Blued Barrel ©Fernwood Armory 2015
"Greek Black"
Black oxide has some similarities to parkerizing as applied to firearms, but uses different chemicals. Like parkerizing, it requires oil to provide good corrosion resistance. We believe that M1 rifles said to have “Greek black” finish are black oxide. M1 and 1903/1903A3 rifles were loaned to the Greek military. Some of these were heavily used, rebuilt and refinished in black, and returned to the U.S. via the CMP (Civilian Marksmanship Program).
Figure 16/Black nitride finish, M1 Garand ©Fernwood Armory 2015
The nitride process we are familiar with can resemble parkerizing in appearance except that it is black. Nitride was not originally used for any of the U.S. military firearms that we are familiar with, only for later refinishing of relatively few. Nitride actually makes the surface of the metal harder than the base metal, and provides even better corrosion protection than parkerizing. The nitride process is sometimes used on barrel bores, and is said to increase barrel life. Nitride will blacken stainless steel, unlike parkerizing, so it can be used for refinishing M1 (Garand) gas cylinder assemblies.
Pitting and Corrosion:
Wet = rust. Rust= bad. Pitting is what is left after rust is cleaned up as well as possible; depressions in the metal surface. Any rust or pitting is undesirable, but minor or cosmetic pitting may not affect a gun’s function. Since many military firearms are quite old, some will have pitting, usually from storage in damp conditions. If a rusty gun or part is blasted and refinished, the existing pitting will not get worse if properly oiled and stored. Pitting can sometimes be filed or polished out before refinishing.
Figure 17/Pitted M1 Carbine receiver ©Fernwood Armory 2015
Corrosion in the bore can be the result of neglect, or corrosive ammunition. Most military ammunition made since approximately the 1950’s is not corrosive but some corrosive ammo is being manufactured to this day. Old ammo can often be looked up according to the lettering on the cartridge base to determine whether it is corrosive. There are cleaning procedures than can be used after shooting corrosive ammo, but if it doesn’t work, the result can be permanent damage to the bore and other parts of the gun. Corrosive ammo can be cheaper than non-corrosive but we never use it. Stainless steel barrels are not necessarily immune to damage from corrosive ammo.
Figure 18/Winchester M1 Carbine ©Fernwood Armory 2015
Some collectors want nothing but absolutely, perfectly, completely original guns. To determine whether a particular gun is original can be difficult. If every part was marked with the manufacturer and the gun’s serial number, this would be easy. Some U.S. military gun parts are marked, some are not. The manufacturer of some unmarked parts can be identified by various characteristics of the part. We use various guides and reference materials, along with our experience, to identify parts in our gun listings.
Figure 19/Smith Corona 1903-A3 Barrel Date ©Fernwood Armory 2015
Figure 20/LMR Garand Barrel with date and proof marks ©Fernwood Armory 2015
Figure 21/Inland M1 Carbine Crossed Cannons ©Fernwood Armory 2015
Absolute proof that any part is original to a U.S. military gun is impossible, other than factory museum examples or other unusual cases where documentation can prove originality. Interchangeability of parts was one of the principal goals of the entire design and manufacturing process for military guns, after all; it’s not difficult to change parts.
Figure 22/Rockola M1 Carbine ©Fernwood Armory 2015
A gun with “all matching” marked parts and correct unmarked parts as far as can be determined, is sometimes obviously put together. How can you tell? Here are a few clues:
- parts are the wrong type for the serial number range
- parts are different in color when they should match
- parts show too much variation in degree of wear or corrosion