Heckler & Koch G11K2 Caseless Assault Rifle

November 28, 2007 7:29 am

It’s surprisingly hard to find a good photograph of the G11 prototypes out there. This rifle, developed in the 1970’s and 1980’s, caught the imagination of RPG designers in both computer and pen and paper role-playing, if not actual militaries. The rifle was entered in the 1979 NATO rifle trials but had to be withdrawn because of cook-offs in the chamber prior to firing once the chamber was hot. Later designs supposedly fixed this problem (common to most attempts at engineering a caseless-firing weapon), and the G11 was again entered in the US ACR trials, where no entered rifle succeeded at meeting the army specs.

Supposedly up to 1,000 of these rifles were manufactured for the West German military, but the rifle never went into full production.

the mauser c96

The Mauser C96

November 29, 2007 7:21 am

The Mauser C96 (first introduced in 1896) was the first semi-automatic pistol in widespread use. With it’s long barrel and high powered cartridge it would be a potent package today. Combined with the unique handle and the integral magazine, the C96 “Broomhandle” has a unique profile that is immediately recognizable (well, at least as Han Solo’s blaster, if nothing else). Over the 40 years that it was in service, many variants were manufactured in a variety of calibers, and even some designed for full automatic fire. All were designed with a wooden carrying box that doubled as a stock.

the mauser c96

The Mauser C96

November 29, 2007 7:21 am

The Mauser C96 (first introduced in 1896) was the first semi-automatic pistol in widespread use. With it’s long barrel and high powered cartridge it would be a potent package today. Combined with the unique handle and the integral magazine, the C96 “Broomhandle” has a unique profile that is immediately recognizable (well, at least as Han Solo’s blaster, if nothing else). Over the 40 years that it was in service, many variants were manufactured in a variety of calibers, and even some designed for full automatic fire. All were designed with a wooden carrying box that doubled as a stock.

Black Widow Mini-Revolver

November 30, 2007 7:11 am

North American Arms manufactures this little mini-revolver in .22 Magnum (and with a replacement cylinder in .22 Long Rifle for those looking for a cheaper round to shoot). Under 4 inches tall and 6 inches long, this is a nice little mini-revolver that remains functional due to the .22 Magnum round.

Black Widow Mini-Revolver

November 30, 2007 7:11 am

North American Arms manufactures this little mini-revolver in .22 Magnum (and with a replacement cylinder in .22 Long Rifle for those looking for a cheaper round to shoot). Under 4 inches tall and 6 inches long, this is a nice little mini-revolver that remains functional due to the .22 Magnum round.

Black Widow Mini-Revolver

November 30, 2007 7:11 am

North American Arms manufactures this little mini-revolver in .22 Magnum (and with a replacement cylinder in .22 Long Rifle for those looking for a cheaper round to shoot). Under 4 inches tall and 6 inches long, this is a nice little mini-revolver that remains functional due to the .22 Magnum round.

top 7 semi automatic(autoloading) shotgins

Top 7 Semi-Automatic (Autoloading) Shotguns

By Russ Chastain, About.com

See More About:

• hunting gear
• semi automatic shotguns
• remington
• benelli
• beretta

Semi-automatic shotguns have been around for many years now, and have become favored by many shooters. Though not as reliable as pump or slide-action shotguns, they are still very reliable, and the reduced recoil of semi-auto scatterguns can help smaller folks handle a shotgun's recoil better than other actions. There are many choices when it comes to autoloading shotguns. Here we will look at seven of today's most popular auto shotgun makers, in alphabetical order.

1. Benelli

Benelli autoloaders use an inertia system, rather than gas, to operate the action. Their Super Black Eagle handles shells from 2-3/4" up to 3-1/2", and there are no gas ports to keep clean. Benellis have a good reputation and a unique style that blends angles with curves for a shotgun like no other. Crossbolt safety located behind the trigger.

Manufacturer's Site

2. Beretta 391

Beretta's gas operated semi-automatic shotguns are all based on the same action, the 391. Built in a variety of variations, including one that handles the blonky 12 gauge 3.5" magnum shells, this action is obviously quite versatile. Add to that the good looks and reliability that Beretta shotguns are known for, and it sounds like a winning combination. Crossbolt safety is in front of the trigger in the trigger guard, a better location (easier to use) than behind the trigger.

Manufacturer's Site

3. Browning Gold

Browning has long had an excellent reputation for fine guns, and their gas-operated semi-auto Gold shotgun should be no exception. Self-regulating so it can handle both light and heavy loads without adjustment, the Gold is also good-looking, which doesn't hurt its reputation a bit. Also available in a 3.5" version that will shoot lighter loads as well. Has a magazine cutoff, which can be handy. Safety is a crossbolt behind the trigger.

Manufacturer's Site

4. Franchi

Franchi's 612 and 620 semi-autos use a user-adjustable gas system, so the same gun handles hot loads as well as lighter ones. Aluminum receivers mean light weight. Magazine cutoff. Crossbolt safety located in front of the trigger. Their 712 & 720 are similar, but have non-adjustable gas systems. The 912 is their non-adjustable 3.5" magnum version of this action. They also make the Model 48, a long-recoil-action reminiscent of early Browning autos, which has a crossbolt safety behind the trigger.

Manufacturer's Site

5. Mossberg 935

Mossberg's 935 is chambered for the whopping 3-1/2" 12 gauge magnum, and uses a self-regulating gas system. This gun was developed for use with 3" and 3.5" shells, so don't expect it to function with dove loads. This gun is only available in synthetic-stocked versions. The safety is just exactly where it belongs - centered on the rear of the receiver for ambidextrous thumb operation, where shotgun safeties should all live.

Manufacturer's Site

6. Remington

Remington's 1100 has been around for ages, and it's going strong. I'm not sure why, since their 11-87 is an improvement on it. The 1100's main disadvantage is that you must only use the shells it's designed for (2-3/4" or 3"). A 3"-chambered 11-87, on the other hand, can handle lighter loads along with 3" magnums. Both are gas-operated and come in a variety of sub-models. Crossbolt safety behind the trigger.
Their newer gas-operated 105CTi is an interesting gun that may or may not be around for the long haul. Its lightweight receiver contains carbon fiber (new(ish) to guns and not particularly attractive to shooters). 3" chamber. The whopping MSRP of $1548 (in 2008) means that it probably won't become a mainstream gun anytime soon.

Manufacturer's Site

7. Winchester Super X2

Winchester's Super X2 autoloading shotgun is gas-operated. Some versions are self-regulating, while some specialized models may include interchangeable gas pistons for use with different loads. Their 3-1/2" magnum version will handle everything from hotter 2-3/4" shells on up. Crossbolt safety located behind the trigger.

Whole genome shotgun sequencing

Whole genome shotgun sequencing for small (4000 to 7000 basepair) genomes was already in use in 1979 ^[1] broader application benefited from pairwise end sequencing, known colloquially as double-barrel shotgun sequencing. As sequencing projects began to take on longer and more complicated DNAs, multiple groups began to realize that useful information could be obtained by sequencing both ends of a fragment of DNA. Although sequencing both ends of the same fragment and keeping track of the paired data was more cumbersome than sequencing a single end of two distinct fragments, the knowledge that the two sequences were oriented in opposite directions and were about the length of a fragment apart from each other was valuable in reconstructing the sequence of the original target fragment. The first published description of the use of paired ends was in 1990 ^[3] as part of the sequencing of the human HPRT locus, although the use of paired ends was limited to closing gaps after the application of a traditional shotgun sequencing approach. The first theoretical description of a pure pairwise end sequencing strategy, assuming fragments of constant length, was in 1991^[4]. At the time, there was community consensus that the optimal fragment length for pairwise end sequencing would be three times the sequence read length. In 1995 Roach et al.^[5] introduced the innovation of using fragments of varying sizes, and demonstrated that a pure pairwise end-sequencing strategy would be possible on large targets. The strategy was subsequently adopted by The Institute for Genomic Research (TIGR) to sequence the genome of the bacterium Haemophilus influenzae in 1995 ^[6] , and then by Celera Genomics to sequence the drosophila melanogaster (fruit fly) genome in 2000 ^[7], and subsequently the human genome.

To apply the strategy, high-molecular-weight DNA is sheared into random fragments, size-selected (usually 2, 10, 50, and 150 kb), and cloned into an appropriate vector. The clones are then sequenced from both ends using the chain termination method yielding two short sequences. Each sequence is called an end-read or read and two reads from the same clone are referred to as mate pairs. Since the chain termination method usually can only produce reads between 500 and 1000 bases long, in all but the smallest clones, mate pairs will rarely overlap.

The original sequence is reconstructed from the reads using sequence assembly software. First, overlapping reads are collected into longer composite sequences known as contigs. Contigs can be linked together into scaffolds by following connections between mate pairs. The distance between contigs can be inferred from the mate pair positions if the average fragment length of the library is known and has a narrow window of deviation.

[edit] Coverage

Coverage is the average number of reads representing a given nucleotide in the reconstructed sequence. It can be calculated from the length of the original genome (G), the number of reads(N), and the average read length(L) as NL / G. For example, a hypothetical genome with 2,000 base pairs reconstructed from 8 reads with an average length of 500 nucleotides will have 2x redundancy. This parameter also enables one to estimate other quantities, such as the percentage of the genome covered by reads (the coverage). A high coverage in shotgun sequencing is desired because it can overcome errors in base calling and assembly. The subject of DNA sequencing theory addresses the relationships of such quantities.

Proponents of this approach argue that it is possible to sequence the whole genome at once using large arrays of sequencers, which makes the whole process much more efficient than more traditional approaches. Detractors argue that although the technique quickly sequences large regions of DNA, its ability to correctly link these regions is suspect, particularly for genomes with repeating regions. As sequence assembly programs become more sophisticated and computing power becomes cheaper, it may be possible to overcome this limitation^{[citation needed]}.

[edit] Next-Generation Sequencing

Although shotgun sequencing was the most advanced technique for sequencing genomes from about 1995–2005, other technologies started surfacing, called next-generation sequencing. These technologies produce shorter reads (anywhere from 25–500bp) but many hundreds of thousands or million reads in a relatively short time (on the order of a day). This results in high coverage, but the assembly process is much more computationally expensive. These technologies are vastly superior to shotgun sequencing due to the high volume of data and the relatively short time it takes to sequence a whole genome. The major disadvantage is that the accuracies are usually lower (although this is compensated by the high coverage).