What do you think of a

[LRRPF52]

If you go to 6mmar.com you will find load data for both the turbo 40 and hagar. There are loads that push 105 gr bullets in the 2800-2900 fps range for both cartridges. The 6mm ar turbo 40 can use lapua brass, the hagar brass is from hornady.

The mystery to me is why we have to be careful to keep pressure down in the grendel to avoid breaking our bolts but the 6mm cartridges are able to come close to the performance of a 6mm BR in an AR cartridge. Why don't the 6mm AR and hagar cartridges have the same pressure limits as the grendel?

I think the MAP of the Hagar is a bit high at 55,000psi. It should really be down at maybe 52,000-53,4000psi because of hoop strength.

If you look at Hodgdon's data for 6.8, they don't exceed 54,000psi, whereas Accurate Powders has data going up to 58,850psi. Nobody ever took real ownership of the 6.8 in its development, so it's all over the map when it comes to working pressures.

The thing I like about the Hagar is that Hornady makes brass for it, and chose to address performance with more case capacity, rather than ramping up pressures over 55ksi, but I would still look for loads that keep the peak pressure down. For mag-feeding, it's limited to the shorter weight 6mm pills, and hi-power shooters will have single load COL lots for the longer distances, pushing the 100-107gr pills.

The full potential of a cartridge like the 6mm Hagar would be realized in a slightly longer action with the ability to load to 2.420". They have clipped magazine loads at 2.340", getting in the 2700-2800fps range with 105's from a 28" barrel. That's where you cut out the front wall of the magazine so the tips can clear it, and allow longer COL.



The 6mm AR's allow you to load the long bullets and feed from the mag.