Ejector Marks on Fairly Moderate .338 Wildcat Load

[Noobie]

Been trying to work up some loads for a wildcat .338 WM variant - larger case capacity. Tried a lot of different powders w/CCI mag primers. The deal is this - the primers aren't really showing much distress except a little roughness near the ejector hole. The ejector hole is rather large and the case head wants to extrude into it. Backed off until the extrusion marks are pretty much cosmetic, same primer roughness.
The barrel is a custom ultra match grade stainless from a very respectable maker, and they installed/headspaced it into an X-bolt. I sent them a brand new reamer. Note that the cases show no signs of stretching near the base so I doubt headspace is the culprit. Velocities have very low spread.
So one of my theories is that the chamber is so smooth and glassy that the case just doesn't have any friction to keep it from setting back against the bolt.
The other theory is that I switched to a wax case lube from the RCBS oil type lube, and the wax is obstinately clinging to the cases/chamber walls or is much better at lubricating things.

 

[338 dude]

Been trying to work up some loads for a wildcat .338 WM variant - larger case capacity. Tried a lot of different powders w/CCI mag primers. The deal is this - the primers aren't really showing much distress except a little roughness near the ejector hole. The ejector hole is rather large and the case head wants to extrude into it. Backed off until the extrusion marks are pretty much cosmetic, same primer roughness.
The barrel is a custom ultra match grade stainless from a very respectable maker, and they installed/headspaced it into an X-bolt. I sent them a brand new reamer. Note that the cases show no signs of stretching near the base so I doubt headspace is the culprit. Velocities have very low spread.
So one of my theories is that the chamber is so smooth and glassy that the case just doesn't have any friction to keep it from setting back against the bolt.
The other theory is that I switched to a wax case lube from the RCBS oil type lube, and the wax is obstinately clinging to the cases/chamber walls or is much better at lubricating things.

Load five cases clean them with alcohol after you're done and see if there's any difference

 

[243winxb]

RCBS oil type lube

Old School. New RCBS 2 case lube is water soluble. New maybe 10 years ago, if not longer.

 

[jessej]

Remove any oil/wax from chamber. Clean your brass.

Also sounds like Hornady or Norma brass. Soft like warm butter.

 

[parshal]

Number 5 on that list is my marker. If I can't get a 1-3x fired case back into the chamber after firing I'm at my max.

 

[Taylorbok]

Pressure Signs, Where do you stop?

Hoping not to start a **** show here. I am curious where you guys shooting the big boomers stop when it comes to pressure? Flat primers, Ejector mark, case head expansion, ejector swipe, heavy bolt lift. What is your method for determining where the limit is. Almost always in this sub peoples...

www.snipershide.com

Bolt lift seemed to be a pretty clear indicator after I dug into it. When I tested the higher loads the ES/SD was brutal so that helped with my decision to choose the charge I did.

 

[Noobie]

243WinXB:
Wasn't showing any of your list of pressure signs except the extrusion into the ejector hole at higher charges. That is about 1/8" diameter or so. That would cause a hard bolt lift just due to the brass sticking into the ejector hole.
Otherwise the fired cases fit right back into the chamber.
338dude and jessej:
Using hornady one shot case sizing wax. Not sure if it is soluble in alcohol. It says 'wipes off', but it also says that it keeps cases from tarnishng (i.e. doesn't all wipe off). Thinking of trying the old RCBS lube to see if that helps, in addition to cleaning the chamber with dry cotton cloth.

 

[can1010]

my guess is we are talking 338 win mag wildcat, belted mag case.
what did you change on the case?
how are you setting up your dies?
how much shoulder setback are you using? hope you are not using the typical die directions to screw down to the shell holder.
what is your case capacity, powders used, bullets, and velocities, barrel length?
you can get those pressure indicators for a couple different reasons not just over pressure.
the more info we have the easier it will be to help.

 

[338 dude]

243WinXB:
Wasn't showing any of your list of pressure signs except the extrusion into the ejector hole at higher charges. That is about 1/8" diameter or so. That would cause a hard bolt lift just due to the brass sticking into the ejector hole.
Otherwise the fired cases fit right back into the chamber.
338dude and jessej:
Using hornady one shot case sizing wax. Not sure if it is soluble in alcohol. It says 'wipes off', but it also says that it keeps cases from tarnishng (i.e. doesn't all wipe off). Thinking of trying the old RCBS lube to see if that helps, in addition to cleaning the chamber with dry cotton cloth.

It's like Frank's hot sauce. I put that **** on everything! Or are you talking about Hornady unique it is more like a wax. It also works well I just prefer the spray.

 

[MagnumManiac]

I will only say this, a stiff plunger ejector will often imprint itself on SOFT brass, even though the loads are perfectly within safe parameters. Have seen this so often, load UNTIL you see other signs in conjunction with the ejector marks. Depending on the the type of action, you may see ejector marks AND cratering, or flattened primers, or you may get sticky bolt lift with the one or other of above. If you get really stiff bolt lift, reduce the charge by 3%.

Cheers.

 

[Laguna Freak]

243WinXB:
Wasn't showing any of your list of pressure signs except the extrusion into the ejector hole at higher charges. That is about 1/8" diameter or so. That would cause a hard bolt lift just due to the brass sticking into the ejector hole.
Otherwise the fired cases fit right back into the chamber.
338dude and jessej:
Using hornady one shot case sizing wax. Not sure if it is soluble in alcohol. It says 'wipes off', but it also says that it keeps cases from tarnishng (i.e. doesn't all wipe off). Thinking of trying the old RCBS lube to see if that helps, in addition to cleaning the chamber with dry cotton cloth.

FWIW; I use the same wax in 30-06 x 150 gr & 300 WSM x 180, 200, 210 gr. All within close proximity to 2900 FPS. No such issues for me.

 

[Mark37082]

I agree that some ejector marks show their faces earlier depending on set-up. It's still a sign of pressure, but can occur way before some of the other signs such as heavy bolt lift. I was getting faint ejector marks below book max charge on Peterson brass. I chose to back off at this point.

 

[Noobie]

It's like Frank's hot sauce. I put that **** on everything! Or are you talking about Hornady unique it is more like a wax. It also works well I just prefer the spray.View attachment 489860View attachment 489861

Thanks for the pics. I have the one shot in a small tin of wax.

 

[Noobie]

I will only say this, a stiff plunger ejector will often imprint itself on SOFT brass, even though the loads are perfectly within safe parameters. Have seen this so often, load UNTIL you see other signs in conjunction with the ejector marks. Depending on the the type of action, you may see ejector marks AND cratering, or flattened primers, or you may get sticky bolt lift with the one or other of above. If you get really stiff bolt lift, reduce the charge by 3%.

Cheers.

I agree that some ejector marks show their faces earlier depending on set-up. It's still a sign of pressure, but can occur way before some of the other signs such as heavy bolt lift. I was getting faint ejector marks below book max charge on Peterson brass. I chose to back off at this point.

No cratering or flat primers. The primer surface appear to be a little rough adjacent to the ejector hole marks. BTW, these marks are from slight extrusion into the ejector hole, not from the ejector poking a hole in the brass base. Brass used was Norma. Norma is known to be soft.