12-25-2023, 09:30 PM
6.5 Grendel, .223 Rem, and .308 Win all share most of the same powders, so a commercial canister powder formulated for their other main cartridges might make the most sense from an industrial standpoint.
For the hand-loader, CFE223 and LVR will deliver the fastest velocities with 123gr bullets, with relatively low chamber pressure compared to other powders.
Youre already well-compressed before you hit the SAAMI MAP, but getting faster speeds than anything else.
For example, under a 123gr SMK (which is a lot longer than a 123gr SST, A-MAX, or ELD-M) you max out at 31.2gr due to case capacity, not chamber pressure, because that load is 48,700psi per Hodgdons pressure test data.
CFE223 is one of the most forgiving powders you can load in 6.5 Grendel in my experience. I ran some pressure ladders with it 2012, and was very surprised at how high it let me go before I saw an excursion from the trend in .3gr of charge weight increments.
That was under 123gr A-AMAX. You have to increase the COL to get more powder in the case, which also reduces pressure until you can build up to it. With 2.275 COL, it allows you to reach much higher velocities akin to adding 4-6 of barrel length.
I was loading through a 16 AA barrel at the time, and easily got into the mid-2550fps region. I only mass-produce the 31.2gr loads though, which run in the 47,000-48,000psi range, maybe even less with a Hornady bullet.
Sierra Match Kings tend to have jackets that resist being driven into the lands more, so they build pressure faster.
The Hornady and Hodgdons load data should be referenced when working with CFE223, but youll be in the 28.4gr to 31.2gr load range under a 123gr SMK per Hodgdons.
Hornady lists the 120gr GMX copper monolith along with the other 120-123gr cup and core bullets, so 31.2gr is the limit with the GMX, not the 120gr ELD-M, 123gr ELD-M, or 123gr SST.
Chamber dimensions and rifling profiles will determine what you are able to do.
For the hand-loader, CFE223 and LVR will deliver the fastest velocities with 123gr bullets, with relatively low chamber pressure compared to other powders.
Youre already well-compressed before you hit the SAAMI MAP, but getting faster speeds than anything else.
For example, under a 123gr SMK (which is a lot longer than a 123gr SST, A-MAX, or ELD-M) you max out at 31.2gr due to case capacity, not chamber pressure, because that load is 48,700psi per Hodgdons pressure test data.
CFE223 is one of the most forgiving powders you can load in 6.5 Grendel in my experience. I ran some pressure ladders with it 2012, and was very surprised at how high it let me go before I saw an excursion from the trend in .3gr of charge weight increments.
That was under 123gr A-AMAX. You have to increase the COL to get more powder in the case, which also reduces pressure until you can build up to it. With 2.275 COL, it allows you to reach much higher velocities akin to adding 4-6 of barrel length.
I was loading through a 16 AA barrel at the time, and easily got into the mid-2550fps region. I only mass-produce the 31.2gr loads though, which run in the 47,000-48,000psi range, maybe even less with a Hornady bullet.
Sierra Match Kings tend to have jackets that resist being driven into the lands more, so they build pressure faster.
The Hornady and Hodgdons load data should be referenced when working with CFE223, but youll be in the 28.4gr to 31.2gr load range under a 123gr SMK per Hodgdons.
Hornady lists the 120gr GMX copper monolith along with the other 120-123gr cup and core bullets, so 31.2gr is the limit with the GMX, not the 120gr ELD-M, 123gr ELD-M, or 123gr SST.
Chamber dimensions and rifling profiles will determine what you are able to do.
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