The 6.5-06 Ackley - Fast and not quite so furious...

The super-fast 6.5mm cartridges have made their way into the mainstream hunting conversation. The 26 Nosler arrived in 2013 and was hailed as the flattest shooting cartridge ever. This, obviously, comes at a price. To get the extreme velocity of 3,200 fps+ from heavy for caliber, 140 grain pills, the 26 can use up to 88gr of powder. This is over 35% more powder than the 6.5-06 Ack uses to produce only slightly slower results. This results is a significant increase in barrel life by using the hyper-efficient Ackley cartridge over the brute strength of the Nosler cartridge.

The round can be made from basically any long action cartridge in the 30-06 family with a 17 degrees shoulder. The reamer designs of Ackley's allow for few thousandths of the neck/shoulder junction area to be jammed into the chamber, which in turn holds the head of the case against the bolt face during fireforming. The two easiest options are necking up the 25-06 or necking down a 270 Winchester. Both options have their strong points.

This few thousandths of jam make it possible to shoot mild fireforming loads as we did at first. A 140gr Hornady SST with 47 grains of IMR 4350 inside a 270 Win FC case worked fine and produced similar speeds as would a 6.5 Creedmoor would have with the same bullet. These rounds had no horizontal point-of-aim shift and could be used for fun or even the short shots in a match. They produced unbelievable accuracy as well. See below:

Unfortunately, the jam eventually began to grate on my nerves as it was significant enough that is seemed to scrape all the grease from the bolt lugs each shot and I could even detect a little bit of bolt lapping and maybe even some galling. Some I decided to go down the rabbit hole of bullet-less fireforming. If you'd like to follow me down that rabbit hole click here to see a whole 'nother blog post on that and we'll see hole deep it goes.

We just got a Remington Varmint barreled version of the 6.5-06 AI and we were able to get to the range and put in some time over the chronograph. Below are the results: Pressure signs in bold.

130gr Berger OTM Hybrid

N560:

56.0 - 3013

56.5 - 3028

57.0 - 3035

57.5 - 3103

58.0 - 3110

58.5 - 3140

58.8 - 3166

59.0 - 3201

H4831:

57.0 - 2945