Ammunition
Ammunition utilizing sabots that extend more forward than the bullets they at least partially encase. The sabots may be formed from one or more pieces. The one-piece sabots may include one or more arms.
1. Field of the Invention
The invention relates generally to ammunition. More specifically, the invention relates to ammunition utilizing sabots that extend more forward than the bullets they at least partially encase.
2. Description of Related Art
The years between the Civil War and the turn of the century were years of great innovation in the fields of firearms design and ballistic sciences. With the advent of self contained metallic cartridges, non-revolving cylinder repeating weapons became practical. Many new designs were tried and marketed, but only one has stood the test of time. From its genesis in the Henry Repeater to the present day Winchester® and Marlin® versions, the lever action carbine has earned and retained a place in the American Hunter's gun rack. The tubular magazine appears to be integral to the handling characteristics that have endeared lever actions to millions of hunters. Both Winchester® and SAVAGE have marketed lever actions without tubular magazine. Each was moderately successful, but neither has been able to curb the appeal of the “standard” lever action.
The cartridge that has become synonymous with the lever action carbine is the Winchester®.30-30. Developed at the end of the black powder era, it was adapted to smokeless powder during the industry's shift to smaller caliber higher velocity rounds. Married to the lever action rifle, the .30-30 cartridge's success is well known. Even though the .30-caliber lever action carbine was never a target or military rifle, its design and handling attributes as a hunting gun have allowed it to remained popular with outdoorsmen. And while bolt action and semi-automatic rifles have drawn many hunters, there are still thousands, if not millions, of hunters using .30-caliber lever action carbines in deer seasons year after year.
Thirty-caliber lever action carbines that utilize tubular magazines suffer from a drawback. In a conventional tubular magazine, the point of one round would rest on the primer of the next round. This situation invites disaster. As a result, .30-caliber lever action carbines with tubular magazines must utilize round nose or flat nose bullets. The shortcoming of this solution is the loss of energy associated with these bullets versus pointed bullets, such as spitzers.
It is generally accepted in the gun press that the minimum amount of terminal energy required to humanely take a deer is 1000 foot/ponds (ft/lbs). Hornady's Handbook of Cartridge Reloading, Third Edition, includes data related to the firing of a .308 caliber, 170 grain flat nose bullet at 2300 feet per second (fps). For such a bullet, the muzzle energy (i.e., the energy at the end of the muzzle) of the bullet is 1997 ft/lbs, the energy of the bullet at 100 yards from the end of the muzzle is 1319 ft/lbs (66% retained) and the energy of the bullet at 150 yards is down to 1064 ft/lbs (53% retained). According to the same publication, starting a .308-caliber 168 grain boat tail hollow point match (BTHPM) bullet (which is a bullet with a pointed front end) at the same 2300 fps, the muzzle energy is 1974 ft/lbs, and the energy at 100 yards is 1705 ft/lbs (86% retained). That is a 30%+increase of delivered energy at 100 yards. The BTHPM bullet still has 1078 ft/lbs (55% retained) at 400 yards. Stated more simply, having to use a flat nose bullet instead of a pointed bullet means less power at normal ranges, or a decrease in the useable range of the ammunition.
There have been at least two major attempts to put pointed bullets in tubular magazines. The French Label (1886) and a Remington® pump action both tried to use pointed bullets in a tubular magazine by canting the rounds so that the points and primers were offset. The French Label round had a circular trough on the head of the cartridge around the primer to catch the point of the next bullet. Neither design stood the test of time.
SUMMARY OF THE INVENTIONThe present ammunition reduces or eliminates the shortcomings identified above. Each round of the present ammunition utilizes a sabot as part of a solution to those shortcomings. As used in this document, a “sabot” is a structure that at least partially encases a bullet as the two travel down the muzzle of a weapon. The sabot should be discarded, or fall away from the bullet, after the bullet exits the muzzle. The present ammunition uses sabots that extend more forward than the bullets they at least partially encase. As a result, a round of the present ammunition that is placed in a tubular magazine is not likely to set off the primer of the round in front of it because the front end of the sabot, rather than the less forward front end of the point of the bullet, is in contact with the head of the more forward round. Consequently, using the present ammunition, it is possible to take advantage of the use of pointed bullets in tubular magazines without modifying any aspect of the firearm.
BRIEF DESCRIPTION OF THE DRAWINGSThe following drawings demonstrate certain aspects of some of the present rounds of ammunition. The drawings illustrate by way of example and not limitation. Like reference numbers refer to similar elements. The drawings are not to scale.
In this document (including the claims), the terms “comprise” (and any form thereof, such as “comprises” and “comprising”), “have” (and any form thereof, such as “has” and “having”), and “include” (and any form thereof, such as “includes” and “including”) are open-ended linking verbs. Thus, a round of ammunition or an aspect of a round that “comprises,” “has,” or “includes” one or more elements possesses those one or more elements, but is not limited to possessing only those one or more elements.
For example, a sabot having a front end, a rear end and a cavity has at least a front end, a rear end and a cavity, but is not limited to only having a front end, a rear end and a cavity. For example, such a sabot may also have two or more arms.
The terms “a” and “an” mean one or more than one. The term “another” means at least a second or more. The term “multiple” means two or more. The term “substantially” means at least approaching a given state (e.g., preferably within 10% of, more preferably within 1% of, and most preferably within 0.5% of, each of these ranges including the given state).
Those of skill in the art will appreciate that in the detailed description below, certain well known components and assembly techniques are omitted so as not to obscure the present rounds of ammunition in unnecessary detail.
The present ammunition uses sabots to prevent point-to-primer contact between consecutive rounds in a tubular magazine, and to prevent damage to the points of bullets that are at least partially encased in the sabots. The present sabots, like traditional sabots, allow a smaller-caliber bullet to be fired from a larger-caliber firearm. Like traditional sabots, the present sabots serve to substantially seal the space between the bore and the bullet. As a result, most if not all of the expanding gases from the ignited powder will not escape around the smaller caliber bullet as the two travel down the barrel. Instead, substantially all of the gases will propel the sabot and bullet down the barrel as if the bullet were large enough to fill the bore.
Sabots are not new. Conventional sabots are usually made of plastic or a light weight synthetic material and are discarded shortly after the round leaves the barrel. Sabot technology has been used with black powder and shotgun slugs. Current shotgun slug technology uses a full length sabot positioned around and extending more forward than an hour glass-shaped slug for use in rifled slug barrels. An example of sabot use with shotgun technology is U.S. Pat. No. 6,105,506.
Sabots have been used in high powered rifles as well. Remington® ACCELERATOR ammunition used sabots to load .22 caliber varmint bullets into larger caliber rounds like .30-06 and .30-30. The purpose of this was to make a hunter's large game rifle more versatile. However, the ACCELERATOR ammuntion solved a non-existent problem and/or did not take into account the number of varmint hunters that reloaded or the accuracy requirements of varminting. Remington® ACCELERATOR ammunition was discontinued in 1998, although some such ammo is still available in the market. While the ACCELERATOR line was not a success, it does prove the safety and feasibility of using a sub-caliber bullet with a sabot in high powered rifles.
Sabots have been used with other ammunition as well. For example, 120 mm Main Battle Tank ammunition is called “Fin Stabilized Discarding Sabot.”
Turning to the present ammunition,
The front end (not visible) of bullet 30 is positioned behind front end 22 of sabot 20. As a result, when round 100 is loaded into a tubular magazine behind another round, front end 22 of sabot 20 will contact the head of the more forward round, instead of the point of bullet 30 contacting the primer of the more forward round. This will help to prevent damage to the point of the bullet. This will also help to prevent the point of the bullet from setting off the primer of the more forward round.
Sabot 20 also includes three arms 46. The arms are spaced apart from each other and separated by separators that are shown in other figures in more detail. The separators are cuts in the wall of the sabot that extend from the outer surface of the sabot to the inner surface of the sabot. The separators make it easier for the arms of the sabot to bend outwardly, or flare, from the center of the sabot when a bullet is inserted into the cavity of a one-piece sabot. The separators also make it easier for the arms of the sabot to flare as the sabot and bullet exit the barrel of the firearm, facilitating separation of the sabot from the bullet.
As shown in
Continuing with
Sabot 20 also includes three arms 46, only two of which are shown in
Continuing with
The separators are intended to facilitate peeling back to the separator ends 48. In embodiments of the present sabots that further include grooves extending from separator ends toward rear surface 44, the arms will continue to separate from each other along the failure points created by the grooves. As a result of this separation, the sabot may more easily separate from the bullet after the two exit the barrel.
In
The difference between the sabot in
As shown in both
For example,
The design of the present sabots will depend on multiple factors, including the diameter of the bore of the firearm from which the round will be fired, the diameter and weight of the bullet, and the material chosen for the sabot. The present sabots may be formed from a variety of materials. Most modern sabots for use in sporting guns are injection molded from heat resistant polycarbonate plastic or nylon. These compounds will resist temperatures up to 500 degrees Farenheit and are formed in one piece, with a recess for the base of the bullet and four to six fluted fingers at the front of the sabots.
The present sabots may be made from these same materials. Another potentially suitable material for the present sabots is pot metal, which may include a mixture of tin, antimony and lead; alternatively, a low-grade brass or copper-lead alloy containing both zinc and tin may be used. Powdered metals may also be used to form the present sabots.
One purpose of the present sabots is to extend more forward than the bullets they at least partially encase. This helps to prevent damage to the front end of the bullet and, as a result, helps the bullet to stay on its intended path after firing. It also helps to prevent contact between the front end of the bullet and the primer of the more-forward round in the magazine. The present sabots should be configured such that they achieve this purpose. In addition, the present sabots should be configured such that the escape of gases around the sub-caliber bullet the sabot at least partially encases is minimized. The forward portion of the sabot should be configured such that it cycles substantially smoothly through the action of the firearm, but contain enough air catching surface that the sabot separates from the bullet shortly after exiting the muzzle. By providing the present sabot with arms, which may be separated from each other by the separators described above, the air drag on the sabot as it exits the muzzle should tend to bend the arms outwardly. As a result, the surface area of the sabot exposed to the air drag should increase and further slow the sabot, allowing the bullet to continue on its intended path, and leaving the sabot behind the bullet and falling away from the bullet.
An example of one arm of a sabot with a configuration that may achieve the smooth cycling and air drag functions is shown in
Continuing with
Examples of sabots that were commercially available at the time this application was filed include those from J & D Components in Orem, Utah, which provides .30-caliber sabots for .22-caliber bullets (the designation “.22-caliber” in this document is shorthand for .224-caliber) and .50-caliber sabots (the designation “.50-caliber” in this document is shorthand for .508-caliber) for .30-caliber bullets. Remington's® ACCELERATOR ammunition was loaded with .30 caliber sabots containing .22-caliber, 55 grain bullets for the .30-06, the .308 Winchester® and the .30-30 Winchester® cartridges. Remington® reported muzzle velocities of 4,080 fps for the .30-06, 3,770 fps for the .308 and 3,400 fps for the .30-30 ammunition. The sabots for these cartridges were not placed more forward then the front end of the bullets they were at least partially encasing, nor was there any need for them to be.
Using the present rounds of ammunition, it is possible to store pointed bullets in tubular magazines. Furthermore, using the present rounds of ammunition, it will now be possible to capitalize on the ballistic advantages pointed bullets have over round nose and flat nose bullets without any modification to the firearm itself.
As
As provided in TABLE 1, the present rounds of ammunition may be used with the following caliber sabots at least partially encasing the following caliber pointed bullets:
The .30-caliber sabots listed above in TABLE 1 may be positioned in the openings of .30-caliber cartridges and fired from any suitable firearm, including a .30-30 lever action carbine rifle with a tubular magazine, such as the Winchester® .30-30 lever action rifle. However, such the rounds of ammunition that include such sabots may be fired from other firearms of the appropriate caliber, including those without tubular magazines, such as handguns.
The .45-caliber sabots listed above in TABLE 1 may be positioned in the openings of .45-caliber cartridges and fired from any suitable firearm, including a .45-70 lever action carbine rifle with a tubular magazine, such as those made by Winchester®, Marlin®, and some importers. However, such the rounds of ammunition that include such sabots may be fired from other firearms of the appropriate caliber, including those without tubular magazines, such as handguns.
The components of the present rounds of ammunition described above need not be made in the exact disclosed forms, or combined in the exact disclosed configurations. Instead, it will be clear that various substitutions, modifications, additions and/or rearrangements of the features of the present rounds of ammunition may be made without deviating from their scope, which is defined by the claims and their equivalents. For example, .45-caliber cases for the .45-caliber sabots listed in TABLE 1 have straight wall cases, rather than cases with a tapered portion connecting a main body and a neck as do the .30-caliber cases shown in the present figures. That is, .45-caliber cases have a main body with a length that extends substantially from the rear end of the case to the front end of the case, the main body having a diameter that is substantially constant along the length. Additionally, .30-caliber cases with straight walls may also be used.
As another example, the cases used with the present rounds of ammunition may lack a rim. As another example, instead of groove that extends around the outer surface of the sabot and into which the front edge of the case may be crimped, the present sabots may be secured to the cases with a friction fit, provided the friction fit is tight enough to withstand the forces associated with recoil and with cycling rounds through the action of the firearm, whichever forces are greater. Alternatively, the present sabots may be provided with crimping notches that are spaced apart from each other. In such an embodiment, 2, 3, 4, 5, 6, 7, or more notches may be provided in the outer surface of the sabot and the adjacent portions of the front edge of the case may be crimped into those notches.
As another example, although the present sabots have been illustrated as having a cylindrically-shaped rear end as opposed to a boat tail-shaped rear end, a boat tail configuration may be provided on the rear end of the present sabots, provided the same does not interfere with the gas sealing function of the present sabots.
As yet another example, the sabots illustrated in the figures are made from one piece of material and include separators that extend beyond the bearing surfaces of the bullets toward the rear end of the sabots. However, the present sabots may be formed from multiple pieces and separators in addition to the cuts used to create the separate pieces need not be provided. For example, one of the present sabots may have an external configuration as shown in
Another alternative that is not shown in the figures is to use a bullet with the present rounds of ammunition that is covered partially or completely by a jacket, such as a metallic jacket.
The claims are not to be interpreted as including means-plus-function limitations, unless such a limitation is explicitly recited in a given claim using the phrase(s) “means for.”
Claims
1. A round of ammunition comprising:
- a case having a front end, a rear end and an opening in the front end;
- a sabot positioned in the opening, the sabot having a front end, a rear end and a cavity, the front end of the sabot positioned forward of the opening; and
- a bullet positioned in the cavity, the bullet having a front end and a rear end, the front end of the bullet positioned behind the front end of the sabot.
2. (canceled)
3. (canceled)
4. The round of claim 1, the bullet having a rear portion with a contour, and the cavity of the sabot being defined by a rear portion having a contour that matches the contour of the rear portion of the bullet.
5. The round of claim 1, the cavity of the sabot having a side wall and a rear wall, the side wall meeting the rear wall at a right angle.
6. The round of claim 1, the sabot including at least one arm, the arm having an end.
7. The round of claim 6, the sabot including at least two arms, each arm having an end.
8. The round of claim 7, the ends of the arms positioned in a closed formation so as to cover the front end of the bullet.
9. The round of claim 7, the ends of the arms positioned in an open formation so as not to cover the front end of the bullet.
10. The round of claim 9, the cavity of the sabot having a forward portion that includes an ogive shoulder preventing the front end of the bullet from being positioned even with or forward of the front end of the sabot.
11. The round of claim 7, the arms being spaced apart from each other by separators, each separator extending from the front end of the sabot toward the rear end of the sabot and terminating prior to the rear end of the sabot at a separator termination point.
12. The round of claim 11, the sabot including a rear wall and a notch extending from each separator termination point to the rear wall.
13. The round of claim 11, the cavity of the sabot having a forward portion that includes an ogive shoulder preventing the front end of the bullet from being positioned even with or forward of the front end of the sabot.
14. The round of claim 1, the sabot including at least three arms, each arm having an end.
15. (canceled)
16. The round of claim 1, the bullet being a.284-caliber bullet.
17. The round of claim 16, the sabot being a.308-caliber sabot.
18. (canceled)
19. (canceled)
20. The round of claim 1, the opening in the case being defined by a front end edge of the case, the sabot having a groove into which the front edge of the case is crimped.
21. The round of claim 1, the round configured to be fired from a.30-caliber rifle.
22. A round of ammunition configured to be fired from a rifle, the round comprising:
- a metallic case having a main body with a rear end, a neck with a front end, a tapered section connecting the front and rear ends and an opening in the front end;
- a polymer sabot positioned in the opening, the sabot a having a front end, a rear end and a cavity, the front end of the sabot positioned forward of the opening, the sabot also having at least two arms spaced apart by separators that extend from the front end of the sabot toward the rear end of the sabot; and
- a bullet positioned in the cavity, the bullet having a pointed front end and a rear end, the front end of the bullet positioned behind the front end of the sabot.
23. The round of claim 22, the round configured to be fired from a.30-caliber rifle.
24. The round of claim 22, the bullet being at least partially covered by a metallic jacket.
25. A round of ammunition comprising:
- a metallic case configured to be fired from a.30-caliber rifle, the case having a main body with a rear end, a neck with a front end, a tapered section connecting the front and rear ends and an opening in the front end;
- a polymer sabot positioned in the opening, the sabot a having a front end, a rear end and a cavity with an ogive shoulder, the front end of the sabot positioned forward of the opening, the sabot also having at least two arms; and
- a bullet positioned in the cavity, at least a portion of the bullet extending forward of the ogive shoulder, the bullet having a pointed front end and a rear end, the front end of the bullet positioned behind the front end of the sabot, the bullet being at least partially covered by a metallic jacket.
Type: Application
Filed: Dec 8, 2004
Publication Date: Feb 9, 2006
Inventor: Troy Byer (Great Bend, KS)
Application Number: 11/007,823
International Classification: F42B 14/06 (20060101);