12-20-2019, 10:35 PM
Some of the baseline assumptions in that comparison are wrong, probably from being transposed across different measuring systems (SAAMI vs CIP).
.223 Remington working pressure and SAAMI MAP is 55,000psi, whereas the CUP is 52,000.
You need to calculate the bolt thrust with even metrics for the cartridges to get relevant numbers in your comparison.
Last time I did this exercise, .223 Remington and 6.5 Grendel had very comparable bolt thrust.
Since the SAKO actions are one of the toughest ever built using the 3-lug design and Finnish engineering, tested in extreme cold conditions as a regular part of their processes, it's one the least ones that would worry me, especially chambering something like 6.5 Grendel with its low working pressure.
Generally with firearms, you're working with a factor of safety of 2, so the SAKO action is one of the best if someone wanted to push a little.
I used to run a very hot load through a .308 Sako 75 tri-lug bolt hunter that the owner had developed for it with the 155gr Scenar. That thing was a laser even with the shorter hunting barrel, and accurate as sin for such a lightweight rifle.
I've also had conversations with the Lapua engineers in Finland about some of the testing they did with a SAKO action and 6.5 Grendel pushed way above max working pressure using 123gr Scenar. They reached speeds that would scare you, with the Lapua brass coming out with loose primer pockets and deformation to the case head. Brass was toast, but no failures.
The Howa action is a copy of the SAKO L461 basically.
I'm not advocating exceeding book pressures, but the SAKO action will handle pressure well. With Grendel, it's better to let the projectile do the heavy lifting for you with energy retention, and allow yourself that nice sight picture throughout the shot.
.223 Remington working pressure and SAAMI MAP is 55,000psi, whereas the CUP is 52,000.
You need to calculate the bolt thrust with even metrics for the cartridges to get relevant numbers in your comparison.
Last time I did this exercise, .223 Remington and 6.5 Grendel had very comparable bolt thrust.
Since the SAKO actions are one of the toughest ever built using the 3-lug design and Finnish engineering, tested in extreme cold conditions as a regular part of their processes, it's one the least ones that would worry me, especially chambering something like 6.5 Grendel with its low working pressure.
Generally with firearms, you're working with a factor of safety of 2, so the SAKO action is one of the best if someone wanted to push a little.
I used to run a very hot load through a .308 Sako 75 tri-lug bolt hunter that the owner had developed for it with the 155gr Scenar. That thing was a laser even with the shorter hunting barrel, and accurate as sin for such a lightweight rifle.
I've also had conversations with the Lapua engineers in Finland about some of the testing they did with a SAKO action and 6.5 Grendel pushed way above max working pressure using 123gr Scenar. They reached speeds that would scare you, with the Lapua brass coming out with loose primer pockets and deformation to the case head. Brass was toast, but no failures.
The Howa action is a copy of the SAKO L461 basically.
I'm not advocating exceeding book pressures, but the SAKO action will handle pressure well. With Grendel, it's better to let the projectile do the heavy lifting for you with energy retention, and allow yourself that nice sight picture throughout the shot.
NRA Basic, Pistol, Rifle, Shotgun, RSO
CCW, CQM, DM, Long Range Rifle Instructor
6.5 Grendel Reloading Handbooks & chamber brushes can be found here:
www.AR15buildbox.com
CCW, CQM, DM, Long Range Rifle Instructor
6.5 Grendel Reloading Handbooks & chamber brushes can be found here:
www.AR15buildbox.com