In the 109 th Congress, two proposals have been introduced to regulate more strictly certain long-range .50 caliber rifles. The Fifty Caliber Sniper Weapons Regulation Act of 2005 ( S. 935 ), introduced by Senator Dianne Feinstein, would amend the National Firearms Act (NFA) to regulate ".50 caliber sniper weapons" in the same fashion as short-barreled shotguns and silencers, by levying taxes on the manufacture and transfer of such firearms and by requiring owner and firearm registration. The other proposal introduced by Representative James Moran, the 50 Caliber Sniper Rifle Reduction Act ( H.R. 654 ), would also amend the NFA to include these weapons, but would also amend the Gun Control Act to effectively freeze the population of these weapons legally available to private persons, and to prohibit any further transfer of these firearms. In other words, H.R. 654 would grandfather in existing rifles, but would ban their further transfer. Consequently, the proposal would eventually eliminate these rifles altogether from the civilian gun stock. It is likely that covered .50 caliber rifles would have to be destroyed or handed over to the Bureau of Alcohol, Tobacco, Firearms and Explosives (ATF) as contraband, when the legal firearm owner died or wanted to give up the firearm. As currently constructed, H.R. 654 includes no compensation provision for rifles destroyed or handed over to the federal government under this proposal. Furthermore, both proposals ( S. 935 and H.R. 654 ) would define ".50 caliber sniper weapon" to mean "a rifle capable of firing center-fire cartridge in .50 caliber, .50 BMG caliber, any other variant of .50 caliber or any metric equivalent of such calibers." Many rifles, and even some handguns, are chambered to fire .50 caliber ammunition, meaning the projectile is about one-half inch in diameter. Opponents of this legislation are likely to note that this definition is very broad and would likely cover .50 caliber rifles that would not be considered "long-range" or "sniper rifles." The .50 BMG caliber round, on the other hand, is an exceptionally large cartridge (projectile and casing), which was once used almost exclusively as a heavy machine gun round. Certain specialized firearms manufacturers began producing long-range .50 caliber rifles in the early 1980s. In recent years, these firearms have gained popularity among firearms enthusiasts; and, in 1985, they formed the Fifty Caliber Shooters Association, Inc. (FCSA) to "advance the sporting uses of the .50 caliber BMG cartridge." The FCSA holds competitive marksmanship matches of 1,000 yards (and longer). The .50 caliber BMG cartridge was developed following the First World War as a "heavy machine gun" cartridge. Adopted by the U.S. Army in 1923, it has seen continuous service ever since. According to one firearms expert, one common variety of the .50 caliber BMG cartridge (12.7x99mm) includes a projectile that weighs 665 grains; whereas, a comparable mid-size rifle cartridge like the .308 Winchester (7.62x51mm) includes a projectile that weighs about 147 grains. Hence the .50 caliber BMG projectile is 4.5 times greater in weight than the .308 Winchester. While a cartridge's ballistic performance depends on the type of projectile, grade of propellant (gunpowder) and other factors, the .50 caliber BMG cartridge casing holds about five times more propellent than the .308 Winchester. By further comparison, the same rounds have: (1) a maximum effective range of 2,000 and 1,500 yards; (2) a muzzle velocity of 2,900 and 2,750 feet per second; and (3) a muzzle energy of 12,000 and 2,400 foot-pounds, respectively. The muzzle energy of the .50 caliber BMG round provides not only increased "knock down" power, but increased accuracy as well. In modern rifles, the .50 caliber BMG round can routinely hit a 55-gallon drum at ranges of a mile (1,760 yards). In skilled hands and known wind conditions, such a rifle can be used to place five shots within a 6-inch circle at a range of over one-half mile (1,000 yards). The FCSA maintains that long-range .50 BMG caliber rifles were first developed for marksmanship competitions and, then adopted by the military as sniper rifles. One of the rifles adopted by the U.S. Army is the M-107 Long Range Sniper Rifle. Outfitted with a 10-round magazine, the M-107 is a semiautomatic rifle, meaning it is self-loading, but fires only one round per trigger pull. It is also outfitted with an "attached optics/electro-optics [scope] that supports all weather, day/night tactical dominance.... " Fifty caliber BMG ammunition comes in a wide variety, so the rifle is capable of delivering incendiary, armor piercing, tracer, and dual purpose ammunition. According to one firearms expert: The primary mission of this rifle is to engage and defeat material targets at extended ranges to include parked aircraft; command, control, communications, computers, and intelligence (C4I) sites; radar sites; ammunition; petroleum, oil and lubricants; and various other thin skinned (lightly armored) material targets out to 2000 meters. Loaded with nine rounds, the M-107 weighs about 32 pounds. For FY2005, the unit price for a single rifle is $14,833 (based on a modular cost of $8.9 million for 600 rifles). The M-107 government contractor—Barrett Firearms Manufacturing Company—produces long-range .50 caliber rifles, which are available to the general public. Equipped with conventional scopes, these rifles range in price from $2,800 for a single-shot bolt-action rifle to $6,750 for a semiautomatic rifle ( new in box (NIB) ). Regarding the availability of armor piercing/incendiary rifle ammunition in the civilian gun market, for the past six years (FY2000-FY2005), a provision has been included in the Department of Defense Appropriations Act that bans the resale of military surplus .50 caliber ammunition, unless it is "demilitarized," so that the refurbished ammunition does not include armor piercing, incendiary, and tracer projectiles. This provision includes exceptions for ammunition that is refurbished for the National Guard or for export to foreign governments for military purposes. While such ammunition introduced into the civilian market prior to the ban is still available, it is a specialty item and not always easily located. Gun control advocates have reported that long-range .50 caliber rifles could be used by terrorists in several deadly scenarios. According to the Violence Policy Center, given the range and power of a .50 caliber BMG round, a rifle chambered to fire this round could be used to bring down a slow/low-flying aircraft. It is also plausible, that a terrorist using such a rifle could punch holes in pressurized chemical tanks, igniting combustible materials or leaking hazardous gases. In addition, such a rifle could be used to penetrate lightly armored vehicles—such as those used by law enforcement and protective limousine services. While these potentialities exist, as pointed out by gun control opponents, long-range .50 caliber rifles have not been the weapons of choice of criminals as law enforcement encounters with these weapons have been few and sporadic. Given the potential destructiveness of these rifles, one option for Congress to consider is more strictly regulating these firearms under the National Firearms Act. Two major statutes regulate the commerce in, and possession of, firearms: The National Firearms Act of 1934 and the Gun Control Act of 1968, as amended. Supplementing federal law, many state firearms laws are stricter than federal law. For example, some states prohibit any possession of machine guns by private persons, require permits to obtain other firearms, and impose waiting periods for firearm transfers. Other states are less restrictive, but state law cannot preempt federal law. In general, federal law serves as the minimum standard in the United States. In 1934, Congress passed the NFA to limit the availability of machine guns, short-barreled rifles and shotguns, silencers, and a "catch-all" class of other "concealable" firearms identified as "any other weapon." Many of these weapons were considered particularly lethal and often the weapons of choice of "gangsters" during the prohibition era (1919-1933). As part of the Internal Revenue Code, the NFA levies taxes on all aspects of the manufacture/importation and distribution of such firearms, and requires that these firearms and their owners be registered at every point the firearms change ownership in the chain of commerce. The NFA required the Secretary of the Treasury to establish a registry of all NFA firearms in the United States that were not under the control of the United States. Today, the registry is maintained by the Attorney General.