With the number of proud owners of these rifles growing daily it is obvious that there are people who love Stoner’s AR-15/M-16 construction are numerous all over the world. Aggressive advertising and influential industrial and military-political lobbying have certainly contributed to making it one of the most popular guns among both servicemen and competition users. A long standing debate is the only thing shaking up this community of firearm lovers, a debate about the gas piston system.
Traditional vs. New
Traditionalists give edge to the direct impingement system, the one that was originally designed by Eugene Stoner. This simple mode of operation suffers from one critical failing: during intensive use, interior of the mechanism quickly accumulates dirt and soot, while hot gasses systematically weaken steel elements, reaching levels when they break and malfunction easily. In the gas piston system, gunpowder gases do not reach the interior of the construction, because they transfer their movement impulse to the head of the piston in the cylinder. Critics claim that this increases mass, that extra moving parts increase general wear and tear and that accuracy is reduced. While its proponents point out much greater reliability and durability of the weapon, as well as easier maintenance. They also deny that decrease in accuracy is significant. While the controversial debate rages on, many manufacturers have embraced the short-stroke piston system. Modification is pretty simple, the mass increase is almost negligible and the weapon silhouette is unchanged. Also, all replacement part and accessories that fit the old weapons (and there are a lot of those on the market), fit the new models as well. The research done in USA show that SR-25 with direct gas impingement has one stop for every 80-100 rounds fired in single-shot mode; in gas piston weapons, this happens 4-5 times less frequently.
Famous “SIG Sauer” has also started using this new system. After the 516 model, they added SIG-716 that uses bigger, heavier and more effective .308 Winchester rounds. Although they are similar in many ways, 716 is much more than simply “upscaled” older cousin, the 516.
Convenient Piston Solution for your Guns
All parts of the gas piston system are enlarged, they became heavier and stronger, mainly to accommodate the larger 7.62×51 rounds. One of the advantages is easy accessibility of the gas system without the need for complete weapon disassembly. It can be done by removing the regulator in the area of forward sight. However, strong piston spring and minimum fit tolerances make a demanding combo, so that procedure may not be as easy as advertised. That may make regular maintenance in service use a challenging task. It is obvious that SIG-716 is primarily meant for civilian use. Also, gas flow regulator now has four modes: off, suppressor use, normal operation and increased gas flow. This is convenient when the weapon is dirty or when using weaker ammunition. This solution was so successful that “Heckler & Koch” company used it in their new service model, the G-28.
A Ranged Weapon
Heavy barrel is 406 mm long and bears the brunt of the responsibility for the 4.2 kg mass of the rifle. That is not much, but capabilities of this weapon become really apparent, only with appropriate high-powered scope, further increasing the rifle’s mass for 1 kg. Add to that 20 medium-calibre bullets and you can feel the dramatic increase in weight. Barrel itself is cold forged, with six grooves and twist rate of 254 mm, this improves the weapon accuracy and projectile stability when shooting targets at long distances. Interior of the barrel and the chamber are chromed, making rifle maintenance easier and preventing corrosion. Muzzle is threaded for easy mounting of flash or sound suppressors. This barrel comes with consistent and reliable accuracy that, depending on the ammunition quality and bullet type can range from 0.8 to 1.5 MOA at distances of up to 500 m. Bullet groupings are somewhat wider but still acceptable even at longer ranges.
Service Rifle – close enough
Free floating barrel is completely a handguard with four Piccatiny rails for mounting additional accessories. Unlike the lighter 516, that uses gunstock, handguard and other Magpul MOE series elements, this new rifle uses MIAD handguard, and ACS adjustable stock. Comfortable, light and fully adjustable, this stock allows the shooter to choose the most comfortable aiming position. In addition, the front handguard can be easily removed during regular weapon maintenance.
Firearm of this caliber is not a usual weapon in 3-Gun practical shooting disciplines. Ammunition costs make many shooters forego the “Heavy Metal” division to which this and other high-caliber rifles belong to. This may seem like an ideal reason for SIG-716 to find its way into regular use of some armed service in the USA. While the guns of this company enjoy a measure of prestige, longarms in USA usually come from domestic manufacturers and omnipresent “Heckler & Koch”. This gun was made with the intent to be adopted as a competition rifle by members of various police and armed forces in the US. And that is just one step from it being introduced in full service use, because most police organizations in the US chooses their own weapon and pays for it from their own budget, this definitely makes it an inventive way to break into a specific market.
The rifle is equipped with fully adjustable flip-up mechanical sights. They are however only a backup for modern optic-electronic devices available. All commands function easily, stopping in the final position, but without loud “clicking” that could reveal a hunter or a soldier. Obviously, a lot of care has been given to details, improving the overall impression of the weapon.
It is possible to get much cheaper AR-10 or SR-25 weapons that are very accurate at distances of 100 m, making bullet groupings of less than 1 MOA, but you would need a select, often expensive, ammunition to achieve that degree of accuracy. At longer ranges, grouping diameter grows disproportionately. On the other hand, SIG-716 offers high, and consistent accuracy even at distances larger than this weapon is commonly used for. In addition, many users sing praises to the comfort and reliability; main cause of firing interruptions for SR-25 model were the clips that SIG delivers with the rifle. Although US Navy has banned the use of polymer clips, it has been shown that Magpul model for .308 Winchester was an excellent choice.
Considering the reputation of this famous company, new 716 model can be expected to do very well.
Sorry meant the precision model marksmen since they just did release a 3-gun and something like the marksmen with 18" barrel and upgraded longer rail with longer rod system and of course the double spring ejector in the firing bolt. Also was wondering if my feed ramp is just the polished gen1 since my BCG seems to be instead of polished and angled more by sig like the gen2s and up. Any help would b great but pretty sure im going to have to call Sig and figure it out. Thank again for the awesome video and showing what this system is able to do and it runs better, cleaner, and cooler!
I def still love this one even if not the new BCG!
Love the video but noticed it looks like u have the new double spring ejector by SIG? How would I go about having sig "fix" this on mine bcuz I and other have got the new "Gen2", I think thats what it's considered, or whatever new gen# SIG716 with the new logo ( SIG in a circle) but still got the old BCG with just 1 ejection spring instead of 2. I want the 2 bcuz have been told and read numerous times that with the 308 u really need that 2nd for helping the ejector last. I'm going to mainly hunting but wants to get into some competition shooting finally bcuz not sponsored and thought this was the PERFECT choice, now I'm wondering if I should have waited for the Marksmen to get released? What r ur thoughts on what I should do, send the gun to Sig, see if JP enterprises BCG or PWS would work better? I've lays wanted the Sig716 since I saw it over a year or more ago and saved almost as long to get it since was more a dream while worked on my 556 i own as well but by PSA.