Basic Rules For Reloading For AR-15's (.223 Rem, 6mmAR, Turbo 40, etc.)
After working with AR-15 for many years, and especially with wildcats, there are a few rules for reloading (of all AR-15 cartridges) to help guarantee flawless feeding and function. These rules are also posted on my website (on the “Info Page” at www.6mmAR.com).
Die sets are readily available for the 6mm Turbo 40, which makes it easy and convenient to get up and running with a Turbo 40.
Rule #1 Generally speaking, when you re-size cases when reloading for an AR-15 you need to leave a margin for error when you resize cases because it's not like a bolt gun where you can manually push down the bolt handle and chamber a round that's a little "fat" or sticky. In addition, an AR-15 extracts fired cases under pressure and the fired and ejected cases can actually be bigger than the chamber they came out of. For these reasons, when re-sizing brass, you need to bump the shoulder of the fired cases between .003" - .005" when resizing. A lot of shooters (particularly bolt gun shooters who are not familiar with semi auto AR-15’s) violate this rule and only bump the shoulder .001" - .0015", figuring they will keep all tolerances very close, hoping for better accuracy, only to find out they will get rounds that will not chamber properly and will jam in the gun.
Good magazines for the 6mm Turbo 40 are readily available (magazines to left and right) A .223 Remington magazine (center is shown for reference. The magazines for the Turbo 40 have much shallower side ribs near the rear of the magazines to accomodate the Turbo 40 cartridges that are larger in diameter.
Rule #2 You need to know at what OAL your bullets hit the lands and keep your OAL less than that for magazine feeding. If you just load bullets at maximum magazine length thinking they should feed in the rifle, you can be absolutely wrong! Especially with the 6mm bullet lineup, there is a huge difference in some of the ogives and bullet tips, some will hit the lands at a much longer OAL than magazine length and some much shorter than maximum magazine length. If you take a bullet that hits the lands when loaded at 2.185" OAL and load it at 2.260" (which is magazine length in an AR-15), the bullet will be .075" into the lands and the cartridge will not likely feed and chamber reliably in an AR-15.
Rule #3 Bullet tips vary, even in the same lot of bullets, so it is always advisable to leave a margin for error when you determine the OAL for loading bullets at maximum magazine length. If a cartridge is binding up in the magazine because you loaded it too long for it to freely move up and through a magazine, you are going to have feeding problems.
The above rules apply to not only the Turbo 40 cartridge in an AR-15, but all other AR-15 cartridges.
Great Lapua Brass Helps!
What makes the Turbo 40 cartridge possible is the widespread availability of great quality Lapua 6.5 Grendel brass. If you have ever handled and inspected Lapua 220 Russian or 6BR brass, the quality is evident, as it is with the Lapua 6.5 Grendel brass. The brass has a very hard case head and web area, with a well annealed neck and shoulder area. This well annealed neck and shoulder area, makes it easy for one to neck down and blow out the 6.5 Grendel brass to form Turbo 40 cases without any issues. The “icing on the cake” is the fact that the Lapua 6.5 Grendel brass is also readily available.
Die Sets and Magazines Are Available
Plain and simple, with a semi automatic AR-15, it is easy to shoot off a lot of rounds (magazine feeding, all you have to do is keep squeezing the trigger). From this perspective two other things are also required to run a successful wildcat out of an AR-15:
1. There needs to be die sets that are easy to use and readily available. In this case Hornady Mfg. “stepped up to the plate” and made die sets for the cartridge; and
2. There needs to be good reliable magazines that will feed the cartridge out of an AR-15. In this case, the commercially available magazines for the 6.5 Grendel are the “plug and play” solution.
The Turbo 40 For Varminting, Competition and Fun Shooting – What's Not To Like?
While the Turbo 40 cartridge started out as a means for high power shooters to gain a competitive advantage particularly at longer ranges and in windy conditions, what quickly happened is varmint hunters and long range shooters (fun shooting, tactical matches, etc.) quickly picked it up for the same reasons high-power shooters did - it offers “big gun” performance with 6mm bullets out of a smaller and more manageable AR-15 semi auto platform. What's not to like about it?