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We're holding a smaller, lower-effort competition while things simmer down enough for me to reboot the Texas competition to allow more people to participate. Those of you that choose to participate, enjoy. This competition is intended to be a brief 1-2 week long effort which should require only a handful of man-hours to complete, depending on skill level. Unlike a proper competition, this has one person who's judge, jury, and executioner (me!), to allow the maximum number of competitors. Consider this a brief interlude before the reboot of the Texas competition (which is likely to pick up more or less where it left off). Accordingly, there will be relatively little fluff and editorializing. Contestants will be given a basic setting and a set of requirements with a description of the unique mission needing to be solved. Beyond that, contestants will be responsible for filling in the gaps on their own, to whatever degree they see fit. Programs required: Solid modeling software, ammunition load development software, ballistic calculator, performance estimators (provided) Expected man-hours: 5-10 Deliverables required: Image of loaded cartridge and projectile, cutaway or exploded view of projectile or projectile + cartridge, cartridge data sheet, bill of materials (including all component masses and materials), ballistic charts (not required to be in graph form), completed performance estimate sheets, any supplementary materials the contestant chooses to provide. The competition will be largely conducted via the SH discord, if you're interested please PM me for a link if you don't already have one. BEGIN FLUFF After the War, the Great Plains became virtually cut off from the rest of the former United States. Governments fractured into small polities based around towns and cities, as local populations realized they no longer were enfranchised as part of a larger economy and logistical network. State governments began to be seen overwhelmingly as distant meddlers who offered nothing in return for their interference in local politics. The area around the Black Hills was no exception. The states of South Dakota and Wyoming disintegrated quickly once the Federal Government of the United States no longer took a direct role in state affairs. A loose government formed around Rapid City, supported by strong manufacturing jobs, traders, and a large ammunition plant that could support paramilitary operations ranging around the Black Hills region and securing the roads that remained passable. Due to this, their influence expanded well into Eastern Wyoming and north to Southeast Montana and North Dakota. The emerging Dakota Union became the primary, if thinly spread, force in the northern plains region. Their most famous agents would be the Sioux Scouts. Unlike most pre-war infantry forces, which operated as part of large combined arms units in a highly tiered structure, the Scouts are highly independent light infantry. Often, Sioux Scouts will travel hundreds of miles unsupported in units as small as pairs, or even the occasional single Scout. While on patrol, they are responsible for their own sustenance and upkeep, foraging for food and shooting with their rifles what they need to survive. For the moment, there are no other organized military forces in the region, and Scouts are tasked primarily with maintaining contact, trade, and awareness of the peoples living inside the Northern Great Plains, and the hills to the West. As part of their duties, they are sometimes called to settle disputes, mete out justice, or are even permanently stationed in affiliated regions to maintain law and order. In times of war, they function in larger units as an army to protect Black Hills from incursion, but this hasn't happened in many decades. There is no distinction between "officers" and "enlisted" in the Sioux Scouts, but there is a basic hierarchy, and Scout pairs will often have a subordinate and a superior. In times of greater trouble, Scouts are also expected to marshal and lead local forces in the local defense. Generally, Sioux Scouts travel on foot or on horseback. They are substantially made up of Indian peoples, although any residents of the Dakota Union may join the all-volunteer force. Currently, the Sioux Scouts are armed with a motley assortment of both manually-operated and semiautomatic rifles in various calibers. The Sioux Scouts have requested a new semiautomatic rifle to replace these, and it has been determined that they require a new caliber to go along with it, hopefully phasing out the assorted legacy calibers in the process. Thanks to the plant in Rapid City, this is a very feasible request for the Dakota Union (and helps sustain jobs in its largest city). You are an engineer at the Rapid City plant, tasked with creating a report on what the new caliber's characteristics should be. Resources, testing facilities, and reams of research are made available to you. The year is 2221. Get to work. END FLUFF The new round must: 1. Produce no less than 700 ft-lbs at 600 yards. 2. Penetrate twenty-four 1/2" pine boards at 600 yards (equivalent to a lethal penetrating shot on a quartered buffalo). 3. Drop no more than 96 inches at 600 yards (2.6in sight height, 100yd zero, 59.0F temperature, 29.92in Hg pressure). 4. Drift no more than 36 inches at 600 yards (2.6in sight height, 100yd zero, 59.0F temperature, 29.92in Hg pressure, 10mph 90 degree crosswind). 5. All performance requirements must be met at 200 ft/s below the spec velocity, except the 600 yard energy requirement, which can be met at 500 yards at -200 ft/s, instead. 6. Produce pressure no greater than 52,000 CUP (brass cased) or 50,000 CUP (steel cased). 7. Use a projectile composed only of any combination of the following: Copper alloy, bronze alloy, lead alloy, iron alloy, steel alloy, tin alloy, nickel alloy, and/or zinc alloys. Titanium, tungsten, aluminum, magnesium, and other exotic metals are not allowed. 8. Minimum magazine capacity must be 20, with a stack height no greater than 5 inches. 9. Cartridge overall length may not exceed 2.8 inches. 10. Cartridge recoil from a 10lb weapon may not exceed 12 ft-lbs. 11. Cartridge must meet performance requirements from a 22" barreled weapon. 12. Cartridge must cost as little as possible. You are provided with calculators to use to estimate these values for the competition. For trajectory, drift, and energy, you must use JBM Ballistics calculator here. Internal ballistics must be estimated via the Powley Computer (just check the pressure box and enter 52,000 CUP for brass or 50,000 CUP for steel). Also please see my guidelines for modeling steel cases here. The pine penetration value must be calculated with this spreadsheet, and the recoil energy with this spreadsheet. For the purposes of this competition, cost per round is determined solely by the materials used. Please reference the material cost sheet here. If you do not already have a solid modeling program, you can use Google SketchUp for free. @Toxn has a lot of experience with it, you might ask him.