CFE223 in cold weather??

[Idaho]

I have used CFE223 in one of my 223s shooting 75g ELDMs at chucks for several years. Temp extremes from the end of March to the end of July run from about 35 degrees to 95 degrees. The powder has done very well as far as accuracy although it is very dirty.

I ordered two new rifle barrels from Criterion in August and just got them at the end of December and of course I could not wait to get them mounted and start to shoot them. Well.......it has not been good. Velocities and accuracy are all over the map and I am using my hunting load that has given me exceptional accuracy for thousands of rounds. Temps have been from the mid teens to the mid twenties. A friend of mine, who used to shoot competitively, suggested that perhaps CFE223 does not do well in these cold temps. Hence this post. Does anyone have experience with CFE223 in cold temps?

He suggested that I try some of my other 223 hunting loads that use AR-Comp and 77g STMKs. I will do that tomorrow. I've also loaded up 5 test rounds with the AR-Comp and the 75g ELDMs. Hopefully I will finally know that this barrel can hold a group. It has the same twist rate and OAL as the barrels I use now. It is also chambered with the same custom reamer as my other barrels. I was really hoping to prove a good load with the CFE so that I can get busy stuffing bullets before chuck season gets here. (I have over 2000 rounds to load) Having fun now.

[Ernest T]

This chart supposedly shows the temp sensitivity of powders - the number to the right of the powder is the change, in FPS, with a change of temperature of one degree. I'm not really sure how much faith we should put into it.

9099

[Dave Hoback]

Yeah, I wouldn’t trust that one bit. Burn rates & temp sensitivity don’t go hand in hand like that. Meaning, we aren’t necessarily going to have a group of powders, numbered in order by Burn rate, and have them ALL be in the same Temp Sensitivity range. Powders just don’t work like that.

The other point, is just because one person has temp sense issues with a powder, doesn’t mean another person will. Yes, some powders are just typically known for temp issues, but it’s not carved in stone. I’ve actually been using BLC-2 for many years in my 223. It’s my favorite powder for it. Granted, I’m not loading 223 for extreme accuracy. My 223 is for AR15’s @ mag length. I might play here & there, loading them longer when I’m trying out different bullets. Just to see. But teeny-tiny groups is not my main agenda. So I’m not eye balling temp sensitivity with it like I do my 260Rem loads. Obviously, if your accuracy is garbage, you should try something different.

[Ernest T]

Yeah, I wouldn’t trust that one bit. Burn rates & temp sensitivity don’t go hand in hand like that. Meaning, we aren’t necessarily going to have a group of powders, numbered in order by Burn rate, and have them ALL be in the same Temp Sensitivity range. Powders just don’t work like that.

The other point, is just because one person has temp sense issues with a powder, doesn’t mean another person will. Yes, some powders are just typically known for temp issues, but it’s not carved in stone. I’ve actually been using BLC-2 for many years in my 223. It’s my favorite powder for it. Granted, I’m not loading 223 for extreme accuracy. My 223 is for AR15’s @ mag length. I might play here & there, loading them longer when I’m trying out different bullets. Just to see. But teeny-tiny groups is not my main agenda. So I’m not eye balling temp sensitivity with it like I do my 260Rem loads. Obviously, if your accuracy is garbage, you should try something different.

That's what I use too because its cheap and readily available. I think I paid just a little over $200 for 8 lbs last time I bought it. I've heard its pretty temp sensitive, but then so am I. I'm not out there in the middle of the afternoon in July nor early morning in January. I'd say the highest temp I shoot in is 90 and the lowest in the mid 50s.

[charlie b]

Yes, they can vary by temp. How much depends on the powder. Note that these are not huge changes. Varget is known as one of the least sensitive and shows 0.3fps per degree. So, a 100 deg change in temp is only 30fps (which is why I use it). Many people do not measure their powder precisely enough to get that low a vel spread on a good day.

Re15 is known to be one of the more sensitive ones at around 1.5 per deg. That would be a 150fps change. That is noticeable by most folks. It is also a concern if you load to max. If your load is ok at 50deg and you are shooting at 100deg you may be over pressure.

Precision shooters will have a DOPE card to show different vel or holds for different temps. Some will change their powder load a little based on weather predictions. Some benchrest shooters load at the range and might change a load based on the temp.

Is it enough to change your group size? Probably not unless your barrel is very sensitive to the vel change. You will know that from the ladder test you did when working up your load. If your 'sweet spot' is very narrow, eg 0.2gn, then a wide temp change with a sensitive powder might throw off your groups. Still not enough to notice unless you are shooting at paper or long range.

So, yes, wide swings in temp affect some powders more than others. FWIW, this is also a problem if you let your barrel heat up too much during a series. Then, if you leave a round in the chamber too long it will soak up that heat (takes a few minutes to do that). Also good to keep any open ammo in a shaded area instead of out in direct sunlight.

[darkker]

Let's follow up on Dave's honest reply, and continue giving actual information; instead of repeating Hodgdon marketing stupidity.

"Temp sensitivity" is 99% ignorance bearing it's testimony.
When a powder gets designed to be "insensitive", which is more accurately said as; when a powder gets designed to compensate for the primer. That is under very specific conditions, and it isn't necessarily the same, in any other set of conditions.

20 years ago, when Dr. Bramwell specifically pressure tested the "extreme" magic of Varget in the 223. It was a steaming pile of dookie, compared to H335.

"But Darkker... I love Varget, and I can shoot MOA all day, err-day!"

I'm sure you can, as I said in the beginning; temp stability is so far over blown...

Powder fouling:
"Clean" powders, especially the 'extreme tactical' flavorings, aren't actually clean. The coatings used on those extruded powders create "Hard Carbon" fouling. Really nasty stuff, that most old tyme cleaners won't touch.
The alternative, is some combination of Tin/Bismuth compounds, which tie up various fouling including copper. Despite the Lies printed by Hodgy, this is 1901 French technology; and can be read about in Hatcher's Notebook.
The tie-up products are very pronounced, and very easily removed. Without knowing they were using it, people have been using CFE powders in the US, since 1935. WC846, WC844, WC748 for just a few examples.

Burning rate charts.
Besides politicians, they are the second most useless item available publicly. Powders change burning rates, based upon case volume, operating pressure, and geometry.
A burning rate chart, ignores that. It is based off a single combination used as the standard. The only ones in aware of as publicly stating their standard, is Norma. They use a 308 with 145-147gr ball projectile; with something like 38gr charges. Then they load that combo with every different type of powder (but same charge amount), and judge which one is "relatively speaking" faster or slower. In case anyone is wondering, no they're isn't a gun large enough to withstand 38gr of Bullseye in a 308 case. Things like that, get "calculated".... You know: pretend powders don't change burning rates, and calculate what they would do, if they didn't do what they actually do.🤣🤣



Cheers

[8mm RUM]

HUMM?
We use it in some of our "smaller" cartridge's 223, 222, and 17 Hornady K I believe.
Any where from 100* to -20* never noticed an issue. I think Varget is a better choice, like stated but it is cheap and on the shelf.
We do run at the top of the load information.
So what ever.

[Blue Avenger]

Works well in .308 Palma case also.

[Whynot]

Maybe I'm just repeating hodgdons stupidity... but anyone that owns a chronograph and lives in a area with extreme temperature swings can verify that temp stability is not just BS marketing... (although they definitely do use it to market- and make some claims that are questionable.)

Lots of things still go into it- single base vs double base- size and shape of powder kernel, case capacity and design- ignition etc. But some powders are influenced more by temp changes (or they exhibit it more at the temp changes that occur in nature). It is also very common to work up a load in cold temp that is over pressure in hot temps- CFE 223 did this with me shooting 60 vmax bullets in a 223-. I have also worked up a load in wintertime with a temp stabile powder that did not cause the same issues in the summer.....

If it is all marketing then I need a new chrono because it has bought into the hype.

*side note- all for Varget getting run down on forums- maybe then the price and availability will return to normal.

[charlie b]

I have not measured H335 or CFE. But, I have compared RL15 and Varget and measured about the same velocity difference as above. Got about the same group sizes, just different velocities.

[gbflyer]

If the current barrel doesn’t like the powder/bullet combination, all the loading success of the former barrel won’t help. Time for a new combination. If that doesn’t work you have a dud barrel. Happens.

[CFJunkie]

I think charlie b is on to something. Measurements give much more accurate results than opinions.

Temperature's effect on velocity with some powders might matter if you are trying to achieve a precise exit time, but I don't think velocity, per se, is a big factor effecting accuracy if you are not right around a harmonic node.
Velocity might impact POI a bit, but it shouldn't impact generic accuracy, as long as you are far enough away from a harmonic node.

But if you move away from a harmonic node by more than 20-30 fps, you might see as much as 0.020 in group size increases.
If you change 100 fps, you could see more like 0.050 inches in group size growth on average.
That isn't much change, so many might miss the difference, especially if measurements are being made by comparing to the sizes of nickels or dimes.:smile-new:

I know many of you don't consider exit time a contributor to accuracy, and interestingly, the many of the same don't think velocity is a factor either.
I base my comments on hundreds of groups shot with about 7 different rifles in 3 calibers that were recorded with measurements of just about everything.
I admit that I am anal about data and spend lots of time analyzing my results.
No apologies for that, but I realize that most people don't have that interest.
I just have been doing it for well over 50 years, so it's more like a nasty habit.

[Idaho]

Update. After several days of shotgun patterns out of my 223 a friend of mine, who used to be a competition shooter, suggested that I try another powder. I still have leftover 223 rounds from another of my chuck rifles. They are loaded with AR-Comp pushing 77g Sierra TMKs and have been very accurate. I took 10 of those and five Lapua cases that I loaded with the 75g ELDMs and headed to the range on Saturday. Note that on Friday I had cleaned the barrel after I got home.
I did not have any fouling shots and the first 5 rounds from the clean - cold barrel made one ragged hole at 100 yards that measured under 1/2 inch! I then shot the 5 rounds loaded with the AR-Comp and the 75g ELDMs and got similar results, 4 bullets in one bughole with one not touching. Still under 3/4 inch. So, as far as I'm concerned the problem is the temp sensitivity of the CFE223.
So now I will wait for warmer temps to verify that the CFE loads I've used for the last 3 years will once again work in the new barrel.
Oh, the range that I shoot at is at my friends house. I let him shoot the last five of the 10 leftover from last year. He enjoyed seeing bullet holes exactly where he aimed. I love it when a plan comes together.

[charlie b]

Those are two of the three best bullets I fired in my .223. The 77gn SMK's are the other one. I used Varget in mine.