CFE223 ok/optimal for .308? Temp sensitive?

[Thebigbaby]

Hunting Montana in November. Plan to do load development the next couple weekends for my AR-10. Have several pounds of CFE223 so rather use that, then go out and buy Varget.

Thoughts?

 

[Bluefish]

I have had good luck with velocity using cfe223 is similar sized cases. It is temperature sensitive, more so from 60+than below 60. I just do testing in cold as that’s the conditions I shoot. Similar to varget sensitivity in the cold. Likes pressure to get best SD and ES.

 

[Thebigbaby]

I have had good luck with velocity using cfe223 is similar sized cases. It is temperature sensitive, more so from 60+than below 60. I just do testing in cold as that’s the conditions I shoot. Similar to varget sensitivity in the cold. Likes pressure to get best SD and ES.

Just to make sure I understand you correctly, if I’m doing load development in warm weather and hunting in colder weather, no need to worry?

Hotter loads with CFE223, I’ll get better SD & ES?

 

[Bluefish]

Just to make sure I understand you correctly, if I’m doing load development in warm weather and hunting in colder weather, no need to worry?

Hotter loads with CFE223, I’ll get better SD & ES?

correct, develop in warm and shoot in cold is safe, but the loads may be 50-100 fps slower. Above 60 deg, change in velocity is around 2 fps/deg, below 60 it’s .5 or so. It’s a ball powder which tends to be more sensitive than stick.
I found that SD and ES get better at higher pressures. I have used it in lower pressure cartridges and you can see them improve as pressure comes up. I started to use cfe223 as it is readily available and offers good speed. I use it in 35 whelen as well and some of the newer data shows it achieves good velocity with heavy bullets.

 

[Thebigbaby]

Thank you.

I loaded up the ladders today. 178 ELD-x bullets, federal large rifle primers, federal once fired brass. 46, 46.5, 47, 47.5 and 48 grains of cfe223. 2.8 coal. 1:10 16” Faxon barrel.

Hopefully the next few weekends I can find some time to see how they do and I’ll report back.

 

[rcook10]

I prefer consistency (read accuracy) to a little extra velocity at long ranges. My CFE loads can range to more than 100fps of variation between freezing and september/early october peak temps. They shoot well but the variability is not worth the trouble for long range. For shooting inside 2-300 yards the velocity is worth it, especially for my mono loads. My 223 62gr ttsx load gets me to 3150fps out if a 22” barrel.