Powder residue on neck and shoulder

[ohiohunter]

I shoot 53g H4831sc out of my 284. Shoots great then one day I notice powder residue on the neck and shoulder. Figured out its most likely due to low pressure and to up my load. Today I shot 54.2gr and still getting residue. My primers looked good so still room to go up, but is there anything else I can do?

I'm not 100% certain where my lands are, but I did however load an extra 0.005.

 

[Garycrow]

Generally powder residue on the neck and shoulders means a low pressure load, but it's not an absolute. I wouldn't use that as a means of determining pressure. A chronograph is the best way to tell if you're getting in the ballpark pressure wise. For the most part velocity equals pressure so if you're getting higher than predicted velocities then you've got higher than predicted pressures. Most other pressure indications like primers, case head expansion, etc. are notoriously unreliable. Absent a strain gauge setup on your rifle a chronograph will give you the best data.

 

[dkhunt14]

If the brass is hard and not annealed the case doesn't seal the chamber. The carbon then goes back the neck and shoulder. Matt

 

[yobuck]

If the brass is hard and not annealed the case doesn't seal the chamber. The carbon then goes back the neck and shoulder. Matt

Thats the first time ive heard that mentioned and it makes sence to me that could be
a cause of that.
Annealing is something many of us never did untill rather recently so that wouldnt be something weve noticed.
How often do you anneal Matt, and do you use the same schedule on both your match
and hunting guns?

 

[dkhunt14]

Thats the first time ive heard that mentioned and it makes sence to me that could be
a cause of that.
Annealing is something many of us never did untill rather recently so that wouldnt be something weve noticed.
How often do you anneal Matt, and do you use the same schedule on both your match
and hunting guns?

I anneal every firing. I have a machine so annealing isn't hard to do. I find it cuts vertical and makes sizing consistent. It helps maintain seating depth and seating pressure. It also aids in sealing off the chamber. There are other things that can cause it like very dirty powder or an oversize chamber. Usually if it goes clean to and onto the shoulder the case is too hard and doesn't seal off the chamber. Matt

 

[ohiohunter]

I do anneal, just not every time. I have a few hotter loads to see if it will seal, but I will anneal my brass and go back to my original load to see if the problem still exists. I also have one piece of new brass loaded w/ my original load to see how that fairs.

I'm shooting lapua brass and this issue is on my 3rd firing. I have annealed at least once, but I cannot remember between which firings... it may have been just before this last round.

 

[dkhunt14]

I do anneal, just not every time. I have a few hotter loads to see if it will seal, but I will anneal my brass and go back to my original load to see if the problem still exists. I also have one piece of new brass loaded w/ my original load to see how that fairs.

I'm shooting lapua brass and this issue is on my 3rd firing. I have annealed at least once, but I cannot remember between which firings... it may have been just before this last round.

Is it a factory gun or a no turn chamber and are you turning necks? The load sounds about right for a 6.5-284. I had a couple a few years ago and I believe that was about what I was shooting. I shot a lot of H4350 also because it shot better.
Cold loads will also do it but it doesn't sound like your loads are that cold. If a new piece of brass doesn't do it, then I would believe it is the annealing. Maybe you need to anneal a little harder. If you don't get them hot enough it doesn't anneal. If annealed properly you don't have to anneal every time. Usually every 3 to 5 firings. I just do it because I shoot competition and I have a machine so it takes almost no time and I get them the same every time. Matt

 

[ohiohunter]

Is it a factory gun or a no turn chamber and are you turning necks? The load sounds about right for a 6.5-284. I had a couple a few years ago and I believe that was about what I was shooting. I shot a lot of H4350 also because it shot better.
Cold loads will also do it but it doesn't sound like your loads are that cold. If a new piece of brass doesn't do it, then I would believe it is the annealing. Maybe you need to anneal a little harder. If you don't get them hot enough it doesn't anneal. If annealed properly you don't have to anneal every time. Usually every 3 to 5 firings. I just do it because I shoot competition and I have a machine so it takes almost no time and I get them the same every time. Matt

This is my fclass gun. I turn the necks. I'm not sure about the chamber as I picked this up used w/ about 100 down the tube.

I think it is the brass hardening b/c the fresh brass only had soot on the neck not the shoulder. I ran my powder up to 54.8gr and no pressure but still residue on the shoulder. The thing that bothers me is this is only the 3rd firing on this brass, so only 2x through the sizing die. Why is it all hard already?

 

[yobuck]

unturned

Is it a factory gun or a no turn chamber and are you turning necks? The load sounds about right for a 6.5-284. I had a couple a few years ago and I believe that was about what I was shooting. I shot a lot of H4350 also because it shot better.
Cold loads will also do it but it doesn't sound like your loads are that cold. If a new piece of brass doesn't do it, then I would believe it is the annealing. Maybe you need to anneal a little harder. If you don't get them hot enough it doesn't anneal. If annealed properly you don't have to anneal every time. Usually every 3 to 5 firings. I just do it because I shoot competition and I have a machine so it takes almost no time and I get them the same every time. Matt

Just assuming your machine is the rotating design where you just add a pc and a pc drops off. Mine is a manual device that uses 2 torches and i also use 750 deg tempilaq on the neck as recomended by the maker of the machine.
Based on what your saying, you can adjust the speed of your machine?
Have you tried tempilaq and if so what temp rating would be best in your opinion? I have experimented with a 1 2 count after it turns black.
No doubt your chambers are tighter than mine also as mine are no turn hunting guns showing just slight resistance when inserting a bullet into an unturned fired case.

 

[dkhunt14]

I am not sure about why it is hard. Usually Lapua is good brass and is annealed real good. Maybe it is because with the mandrel and turning it helped harden it. If not maybe your clearance between the neck and chamber is great and you get lots of movement when the brass fills the chamber upon firing and then when you size it back down. If you work brass hard it gets hard.

It would be nice to know the chamber neck diameter and the loaded round diameter to see how much clearance you have. If you new who chambered it he should know. A lot of gunsmiths stamp the number on the barrel especially if it is a tight neck. Matt

 

[ohiohunter]

My fired brass measures 0.320" and my brass thickness measures 0.015"... that puts my loaded neck diameter at about 0.314"

I'm going to clean up my brass and anneal it for a little longer. I anneal on a friends machine so I'll pay a little more attention on how long the case is exposed to heat.

 

[dkhunt14]

Mine has 2 motors on. One is a small motor that spins the case and the other is a stepper motor that turns the other motor and case into the flame. The stepper is controlled by dip switches. The times are 1/4, 1/2, 1, 2, 4 and 8 seconds. They can be added up and for the time. Like 2 and 1/4 and 1/2 is 2 3/4 seconds. You set the case in a holder and push a button and the motor holding the case starts to spin while the stepper motor turns it into the flame. When the time is reached the stepper turns it back out the flame and turns it upside down and shakes it so it comes out. It then goes back to the start position and you set another case in it. I use Mapp and a Mapp gas torch. It takes about 2 seconds to do a WSM. I am thinking of switching to propane because the time is greater and if you are off a 1/4 second it won't get as over heated like Mapp does. I watch the flame and when a case goes into the flame the flame is blue and when the case gets hot the blue turns to yellow and walks around the case. When the yellow gets to the back it is done. If you have the lights off it would just start to turn a light orange. I also put the heat more on the shoulder and not on the neck. I want the shoulder and upper body annealed some. When they are done it looks just like a Lapua case from factory. Matt

 

[DocDoc]

Ohio, are you sure of the loaded diameter? If the neck wall is 0.015, times 2 plus .264 = loaded 0.294 approximately. A 0.320 fired diameter seems awfully big and necking it down to hold a 0.264 bullet would be a lot of work hardening.

 

[ohiohunter]

Its a 284.

I loaded up some virgin brass and no residue, so looks like the brass may in fact be a little stiff. I'm going to anneal tonight w/ some extra heat and see what happens.