This avenue of research is all about developing a next generation caliber for intermediate carbines. The 6MM Riggs is based off of the 5.45x39 Russian's ballistic capabilities and bullet shape while retaining the 5.56 Nato case that we all know and love. The natural question is why. Why do we need yet another carbine caliber?

Whether you're a fan of .300 AAC, 6.8 SPC, 50 Beowulf or any of the others out there, they all have the same issue. They are all designed for CQB applications, or have their own funky cases that mean we have to get new mags or uppers or both.

The benefit of 6MM Riggs is it's backwards compatibility with current platforms. The total length and case diameter mean that using standard AR mags is perfectly fine. The projected weight is around 80 grains which is just slightly heavier than top end .223 match cartridges. This means chamber pressures can remain within safe limits for an AR bolt without sacrificing range. All of this adds up to a very cool reality. Changing over to 6MM Riggs will only require the changing of feed ramps, chamber, and barrel.

The bullet itself is 5.45x39 scaled up to 6mm meaning its BC will be almost identical and its terminal ballistics should show a drastic improvement over 5.56.

Who is this for? Its for everyone. 6MM Riggs has good potential in, precision shooting, military, law enforcement, and small game hunting applications.

If you want to see it made into a reality however, HKT can't do it alone. Bullets have to be turned, cases modified, rifles manufactured, and ballistic tests performed in order to bring the 6MM Riggs to market.

Please consider supporting this project either by donating or helping to spread the word about this project and other research ventures available on here. .