Chrono data: CFE 223 in 223 Rem w/ 50-grain bullet

B

brians356

Beginner
Dec 3, 2012
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DrMike asked me to publish my results for CFE 223 in 223 Rem.

(Velocities from Chrony Beta Master @15 feet. Average, extreme spread for 3-shot groups.)

Rifle: Rem 700 VS
Barrel: 26"
Ambient: 60 f.

Cartridge: 223 Rem
Case: RWS
Powder: CFE 223
Primer: BR-4
Bullet: TNT 50-gr
BOAL: 0.69"
Jump: 0.020"
COAL: 2.34"

Chg_ Avg_ES
28.5 3330 11
28.7 3350 84
29.1 3393 28
29.3 3434 72
29.5 3470 76
29.7 3486 61
29.9 3501 24

Notes: Mild bolt lift resistance at 29.5 and progressed moderately to 29.9. Primers appeared normal. No loose primers.
 
These are preliminary groups, looking at velocities and vertical POIs, vertical dispersions, velocity deltas and ESs mostly. (Following Erik Cortina's approach, thread active over on accurateshooter.com). I haven't started tuning seating depth.

In light breezy conditions, not worrying about horizontal, groups overall could be classed as 3/8" to 5/8", the best being 29.1 gr where three bullets only left two holes touching side-by-side (i.e. "lazy 8").

Based on POI shifts and velocity changes, I am going to fine tune around that 29.1 @3400 fps.

Any observations on my data vs the QuickLoad data you sent me?

FYI without trying to settle the powder (it will), the 29.9 gr pretty much came up to the base of the flat-based TNT, which as seated is only engaging slightly less than 1/2 the neck.
 
I believe you are correct to focus on the 29.1 grain load. Adjustments in seating depth may just give you slightly improved accuracy. It seems apparent that you won't get a lot more velocity out of that particular load. Looking at your data, that particular load has a very good ES (and presumably a low SD) with the 29.9 grain load being marginally better, if at all. Most of your loads show good technique. Were that my rifle, I believe I would do precisely as you suggest and focus on a good load that has no obvious pressure signs. That is still a good velocity that should work well in your rifle.
 
Yes, seating depth tuning will be for accuracy, but of course if I seated the bullet a lot deeper (not going to happen) it would reduce net case capacity, and so could change the velocity-related responses as well.

More fun to come ...
 
Here's what boggles my mind:

Hodgdon's published data, and also an article by Steve Gash about CFE powder they published in their 2013 reloading annual magazine, both are waaay more optimistic than my results:

Hodgdon Manual (Speer SP 50-gr, 24-in barrel, WSR primer):

28.5 gr -> 3505 fps


Steve Gash (TNT 50-gr, 22-in barrel, BR-4 primer):

28.0 gr -> 3444 fps


My results (TNT 50-gr, 26-in barrel, BR-4 primer):

29.1 gr -> 3393 fps

How to reconcile my missing velocity? It's not just the chrono (could be reading low I suppose) but I don't encounter any pressure signs until 29.5 grains, and they are mild signs.


Also, Hornady publishes (V-max 50-gr, 26" barrel, ?? primer):

28.8 gr -> 3300

... so Hornady is more in line with my results.


Your QuickLoad data for my components suggests 28.8 gr -> 3428 from 26" barrel, which is about what Gash saw from only 28.0 gr from a short 22" barrel!

The data are all over the map, which suggests, to me, that, at least with lighter .224 bullets, CFE 223 is somewhat erratic and sensitive.

Any thoughts?
 
I've seen posts where people believe its a twin to blc2 but w/the cleaner additive.
I've just started playing with it in 7-08 and when I use blc2 as the powder in quickload my results are really close.
If it truly is a specialty powder some of these news ones seem to react different in different cases.
I guess all one can say is watch the chrono and see what's going on!

As far as how different people and guns are getting different results that's the nature of reloading. Differing brass capacity, freebore, chamber dimensions, throats, barrels.....all create differences. Sometimes all the differences cancel each other out...sometimes they keep going in the same direction and make a huge difference.
Just this last week I had an unpleasant deal w/what happens when you change lot numbers on powder. I was loading 58 grains re19 under a 180 bt for a super accurate but mild load of 2640 fps in my budfies 3006. I was getting low on powder so picked up another pound. Now w/the same brass bullets and primers my speed dropped to a anemic 2550 and accuracy is gone.....aaaaarrgh.
 
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