Starting load and hard extraction

wce323078

wce323078

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So I started to work up a load for my rifle in .308 using CFE-223 powder Hornady 168 grain BTHP match bullet. So with a starting load of 41.0 of CFE-223 I was getting hard extraction, and case was blacken all around the neck.
By the way military case IK. I seem to recall that this might be considered normal if not enough pressure to force the case to expand to fill the chamber. Load info came from Hornady book and was about half way up the chart at around 2300 fps.

On the Hodgdon site that is starting load. their starting load is for Barnes bullet.
for sierra hpbt it is 46.6.
Big difference in starting loads.

so with no signs of pressure Etc. I am good to go?
 
Is this the same barrel you have issues with in the past?

Hard extraction with a starting load is not something you want to have.

Consider a factory name brand brass just to make sure you aren't creating another problem. Also confirm the length of the throat in case it is overly short.

Always check fired case clearances... Assume nothing, check everything.

Jerry
 
If I read your post correctly, you're using military brass which is typically thicker than commercial .308. If you're using .308 data, you may be getting higher pressures than you think.
 
Mystic no different rifle same make. I measured the cases at the case head web area just above extractor grove .470-.471 actually half way in between and neck measured .344, .342 .342 this is with a proper mic.
Factory case same rifle FED. .469/470. .469/.470 neck .344 .344.
factory case Nosler .469/.470 .469/.470. neck .344 .344
Primers on all cases look normal and all look exactly alike.
I haven't measured the throat on this one yet, I will do that. one thing I just noticed is all cases show black on the neck Factory just the top 1/8 and the reloads most of the neck ends about 1/16 above the shoulder flare.

So just after I had the hard extraction I went back to the factory cases ( the ones I measured above no hard extraction) That made me think powder/gases might have had something to do with it as that seems to be the only difference between the two. But what do I know.
 
Well - You are using military cases:

1) Likely once fired in a military chamber, and possibly oversize at the base. Hard to resize at the base, giving extraction issues. (Poster above asked if you had difficulty chambering as well ....)

2) The soot ring implies low pressure. However, military brass can have a lower case volume, which will cause a pressure rise. Common rule of thumb is to reduce loading by 5% over book values.
 
STay with the brass that doesnt have issues... learn the min/max of this rifle. Learn what is the proper shoulder bump to work for this rifle.

Once you have a firm understanding of how to reload for it, by all means try the military brass again.

Without experience, it gets tough trying to debug problems all the time.

Jerry
 
What is the actual velocity? I've got a few rifles that don't make it past the starting loads, but the speed is there.


Sooty necks can mean low pressure but can also mean hard necks.

What part of the extraction is hard?Hard bolt, lift, hard camming on the primary ramp, or everything opens up but its still a ##### to drag back?
 
I cleaned some brass with a brass wheel and sandpaper one time and it felt fine but stuck in chamber like yours . Maybe polish the chamber ?
 
Soft brass like hertinberger has less spring to it and has been slightly harder to extract even with loads running the proper speed and pressure.
 
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