CFE223 on 308 - Radically different start and max

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Holderofthehorns

Holderofthehorns

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Finally, a first post.

OK. I've been reading as much of this forum as I can in the last few weeks, as I am a noob reloader.
I have only 1k 9mm completed and learned a lot there. The 9's shoot just fine.

Now for the .308!
I have lots of once fired Norma brass. Fired in my own rifle. 26" Rem 700 Varmint
It is all cleaned, de-primed, trim (checked only, all OK) neck sized only and now re-primed.

Load data:
Using SMK 168 HPBT
Lyman 49th has no info on CFE at all on the 308/168 page.
Hornady 9th offers Start 38.3 grains and Max at 45.7
Hodgdon website Start 46.6 and Max at 49.0

So, confusion enters here. Hodgdon Start is above Hornady's Max. <==
Who should I trust? Or should I just ladder up from 38.8 in 1 grain steps until 49, (checking for pressure signs)?

My next step is measuring the powder.
The question is: Would you start at 38.3 or 46.6? The lower may not be the safer.

Thanks in advance for any answers.

HolderOfTheHorns
 
Use Hodgdons data, start at about 47 and work up .5gr increments to where ever you want to stop. Take that best load and fine tune +/- .2gr and reshoot, and your done. Hornady's data is way too low.
 
Is CFE223 an ball powder?

I don't know how you'd get 49g of anything in a .308 case and have any room left for the bullet
 
Holderofthehorns said:
Hornady 9th offers Start 38.3 grains and Max at 45.7
Click to expand...

To be fair to Hornady, they don't, of course, list data for the SMK since it isn't their bullet. But for the 10th edition of their manual in their 168 gr bullet category for the .308, the max is 47.2 gr of CFE223. (That's actually the max in the 9th edition also - 45.7 gr is one slot below their max.)

ETA:
Be very careful if you choose to approach 49.0 gr. Your rifle and the rest of your components are NOT the same as the Hodgdon folks used when they worked up their data. You could end up over SAAMI max pressure even before you get to 49.0 gr. You probably already knew that, but I thought it worth a mention since you are relatively new to reloading...
 
Last edited:
I don't know how you'd get 49g of anything in a .308 case and have any room left for the bullet
Click to expand...

CFE223 is incredibly dense...more than most powders. I have no idea though, what the load in 308 should be.
 
Good answers, Thanks.
Hodgdon did make the powder.
The "new guy" ain't going anywhere near max 49.
I think I'll start at 46.5 and ladder up to 48.5
Should I get a node or two I'll focus on the lesser node.

Thanks for the advice and mild correction. Hornady does not say SMK, but has a whole catagory called "168".
 
Nature Boy said:
Is CFE223 an ball powder?

I don't know how you'd get 49g of anything in a .308 case and have any room left for the bullet
Click to expand...

Yes, 49g fits. But that is the about limit without compressing. Might squeeze another .3 or so. <== I don't need to go there.
 
The Hornady data is probably low to maintain safe pressures for all their bullets, including the bonded bullets and solid copper.

The Hodgdon data is specific for the SMK. They have separate (much lower) data for the 168 grain Barnes copper bullet. Bonded and solid copper bullets usually need lower powder charges than the thin jacketed, soft core of the SMK.

Start at the min, work up carefully, watch for pressure signs, favor accuracy over speed.

CFE 223 is a good powder for a new reloader. I have not experienced sudden increases in pressure with small increases in powder charge.

A chronograph can also be really helpful for a new reloader - stop when you get to the velocity listed for the max charge, even if you are not to the max powder charge yet. There is no free lunch. Higher velocities come from higher pressures, and seeing high velocity as a pressure sign is much easier for new reloaders than seeing signs of pressure in the brass.
 
Another thing you can look for with a chrono is that near max the curve flattens out. You get less of a velocity increase with more powder.
 
Holderofthehorns said:
Yes, 49g fits. But that is the about limit without compressing. Might squeeze another .3 or so. <== I don't need to go there.
Click to expand...
There is something fishy with the online data and I personally wouldn't trust it. Note the first list shows a compressed load yet not the lower one.
36943527255_7657a44a89_z.jpg
 
Load Master said:
There is something fishy with the online data and I personally wouldn't trust it. Note the first list shows a compressed load yet not the lower one.
Click to expand...

The SMK is about 1.215" long and the TTSX is about 1.418", so with both seated to the same COL of 2.800", I think we have the answer...
 
climbnjump said:
The SMK is about 1.215" long and the TTSX is about 1.418", so with both seated to the same COL of 2.800", I think we have the answer...
Click to expand...
Maybe I'm confused. If the TTSX is 1.418 - the SMK, 1.215, doesn't that mean if the COL is the same on both that .203" more of the bullet is into the case volume, reducing the available area for more powder as shown? I don't get it.

Update, now I get it.... Dua moment in my head. I had it reversed.
 
I saw both of those Hodgdon charts, seemingly similar with way different charges. Bullet length difference is the answer (posts 12 & 13 above).

Well, since I'm using SMK 168's I did use that SIE HPBT data above. Loaded 0.1g increments from 46.6 to 48.5 Bet I find a node in there somewhere.
Now I need an hour at the range.

I really enjoy reading this forum, as folks usually show the thinking behind the decisions. The "why" is important to understand.
 
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