Is inconsistent soot on the neck of fired cases my problem?

Blaster01

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Sorry for the long winded post but I'm really really curious. So I've tried a couple different powders and a couple different bullets in my fierce 300 prc. I can shoot the factory 225s half inch all day. But I cannot find a solid load with handloads. Granted I'm new to reloading so it very well could be something I'm doing, I'm just hoping to check this off the list of possibilities. The first picture is what the neck looks like after firing every case on virgin, 1x, and 2x adg brass. I'm noticing that the soot on the outside of the neck is not consistent or uniform. Sometimes it goes down all the way to the neck shoulder junction and sometimes it does not. And it's spotty going around the neck. The 2nd picture is of factory hornady 225 eldm ammo. The soot on the neck looks more uniform and it's consistent like that on every fired case. Any ideas what's going on or if this is possibly a reason I'm not finding any accuracy with handloads?
 

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Soot deposits, or the lack of them is rarely the problem. Do you have a mentor? The fix, is a little long for a post. You need a systematic system for load development.
I have a guy that's been helping me quite a bit but our schedules haven't allowed us to link up in person yet. I've never actually met him but he's very knowledgeable. I have a system but I think I just don't know enough to know if it's right or not. I've loaded a few loads that shot half inch groups in other rifles. But nothing consistent yet.
 
One thing I noticed in the first pic is the taper on the case month. Looks like you have been over aggressive with deburring you only need to deburr the neck not taper it. Think of the case as a gasket that seals off the chamber so all the gasses and bullet goes forward. The second pic looks normal for a fired case. We would need a lot more info. Sometimes the wrong powder for a given application can cause soot to bypass on the neck a little also a light charge that don't properly seal the chamber can cause the neck to be sooty.

PS: I agree with the above post by TB
 
The soot is normal, as in its the small amount of blowback that occurs before the shoulder expands into the datum.

If you using handloads & then factory I would expect there to be some difference between the two.

However if you have excessive headspace then you will start seeing other problems like split necks, case head separation etc

How are you sizing your brass??
FL or NK?

Did you size the virgin brass or just shoot it out of the box?
 
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One thing I noticed in the first pic is the taper on the case month. Looks like you have been over aggressive with deburring you only need to deburr the neck not taper it. Think of the case as a gasket that seals off the chamber so all the gasses and bullet goes forward. The second pic looks normal for a fired case. We would need a lot more info. Sometimes the wrong powder for a given application can cause soot to bypass on the neck a little also a light charge that don't properly seal the chamber can cause the neck to be sooty.

PS: I agree with the above post by TB
Yeah I just realized yesterday I have been overdoing it on the deburring and chamfering. I have them both set up on an electric case prep center but I'm going to go back to doing it by hand. Maybe that will help.
 
The soot is normal, as in its the small amount of blowback that occurs before the shoulder expands into the datum.

If you using handloads & then factory I would expect there to be some difference between the two.

How are you sizing your brass??
FL or NK?

Did you size the virgin brass or just shoot it out of the box?
Full length with a bushing. I have whidden dies. And yes all of the virgin brass was sized before shot.
 
Full length with a bushing. I have whidden dies. And yes all of the virgin brass was sized before shot.
Ok, so how far back is your shoulder being sized??

You need to be able to measure this!

If you don't have headspace gauges imo they are a must have in handloading, as is a comparator.

It could be part of the reason your handloads aren't accurate but then the reason for that could be many things.

We would have to know everything your doing in your process to work out what the inconsistency is.

Ive heard that ADG Brass is very good which is always a good start.

How did you work up you loads??
 
Ok, so how far back is your shoulder being sized??

You need to be able to measure this!

If you don't have headspace gauges imo they are a must have in handloading, as is a comparator.

It could be part of the reason your handloads aren't accurate but then the reason for that could be many things.

We would have to know everything your doing in your process to work out what the inconsistency is.

Ive heard that ADG Brass is very good which is always a good start.

How did you work up you loads??
Shoulders are pushed back 2 thousandths. I have a comparator and use the .420 shoulder bump gauge that whidden sent me with it. I have been refining my load work up process but in short I shoot a ladder test over a magnetospeed. Either at 100 yards or 300 yards depending on how much time I have that day (two separate shooting spots and the 300 yard one is a lot farther away) I do that to get an idea of velocity and hopefully find a node but I haven't quite figured out how to pinpoint a node by looking at just the velocities yet. I also use the hits on target to help find the node. And then I shoot groups at various powder charges within that node or multiple nodes. And then if one looks good I do a seating depth test.
 
Reloading is a long education. I am still learning. I have never worried about soot on the neck but have wondered about it. Do know that if you get it around the primer hole you need to worry.
 
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