Blew a Primer _ Analysis

[Edd]

Well you might want to keep it zipped until you know what you're talking about!!
This isn't your first rodeo (mouthwise)

I know what I'm talking about, pressure. And I do expect someone to get hurt and I I do hope I'm wrong.

 

[WildRose]

Phorwath having shot a lot of RL26 in the 7mm STW, 300wm, 300 Rum and a few others with your case size and projectile weight it seems you should be within, or very close to safe pressures.

I am however unfamiliar with the bullet you are shooting so I wonder about bearing surface compared to say the Peregrines and Barnes TTSX. Do these have the same cannelure grooving or are they slab sided?

I've found the grooved monolithics run much faster and at lower pressures than those that are slab sided.

 

[WildRose]

I know what I'm talking about, pressure. And I do expect someone to get hurt and I I do hope I'm wrong.

Then what exactly do you recommend?

 

[Edd]

Then what exactly do you recommend?

Less pressure.

 

[Pdvdh]

shot those bullets in my 300 win mag with rl-26 they did pressure up quicker than I thought they would 73.0 gr hit 3017 fps definite ejector marks primers loose and brass is done on three firings

Interesting. I'll learn more after a few more field trips and firings.

Will start with a little less powder, and then venture forward again. But I may wait until I get some new parent cases manufactured by RWS.

 

[MudRunner2005]

Those are all possible causes but given the fact that it just happened to both of us with different powders, bullets, etc, I would say there is a 90 percent chance it was brass! I have 1100 rounds with no issues until I used a new lot of brass this fall.

Oh, my bad Rich, I didn't see where you had the same issue. Yep, that does sound like a brass issue.

 

[MudRunner2005]

I'll take a few more measurements on the fired casing. Will double check some things to the extent I can. I'm confident the case length wasn't excessive, but will measure the fired case length to establish the certainty of it.

Higher pressure should have yielded higher MV, no? The LabRadar confirms substantially less MV on the case with the blown primer. The reduced MV is in line with the reduced powder charge and the anticipated lesser pressure.

This is why I initially, and tentatively, point the finger at the Hornady casing.

Yeah, after hearing of Rich having the same problem, it sounds like a brass issue. I was just tossing out different ideas and scenarios for others incase they also have a random primer blow, when they shouldn't be over pressure.

 

[Pdvdh]

Yeah, after hearing of Rich having the same problem, it sounds like a brass issue. I was just tossing out different ideas and scenarios for others in case they also have a random primer blow, when they shouldn't be over pressure.

Appreciate your insights and the effort to help with the troubleshooting process.

 

[elkaholic]

Oh, my bad Rich, I didn't see where you had the same issue. Yep, that does sound like a brass issue.

No problem mud! At least you were being constructive with good intentions!

 

[MudRunner2005]

No problem mud! At least you were being constructive with good intentions!

That's all I ever try to be. But sometimes folks take it wrong.

 

[elkaholic]

I know what I'm talking about, pressure. And I do expect someone to get hurt and I I do hope I'm wrong.

Of course it was PRESSURE DUH! If the loads we're far below max safe loads that we BOTH shot previously and his velocity was also down, does that make sense to even you that it might just be something besides an overload?? What is really offensive is your insinuation that I do things without caring about anyone's safety, and I don't know how else to interpret it? Even if that was the case, your comment was made with no foreknowledge of what a safe load is or isn't! Maybe we should load to 308 velocities so your interpretation of safe pressure is satisfied! The reason I said
this isn't your first rodeo is you have a history of this, and I for one, and fed up
with it!

 

[WildRose]

Appreciate your insights and the effort to help with the troubleshooting process.

I finally got my hands on some RL17 so I'm going to start reloading for the .375 Ruger probably this week. On top of the 80 or so once fired cases I have from shooting factory Hornady ammo I picked up another hundred new Hornady cases. If I see any of the same issues I'll let you know.

 

[WildRose]

Less pressure.

Why don't you tell us exactly what pressure he's running since you seem to so sure that's the issue?

 

[Pdvdh]

I finally got my hands on some RL17 so I'm going to start reloading for the .375 Ruger probably this week. On top of the 80 or so once fired cases I have from shooting factory Hornady ammo, I picked up another hundred new Hornady cases. If I see any of the same issues I'll let you know.

Nice. Yes, please let me know if you see any sign of soft case heads. I may be moving to the 8X68S RWS brass, but in the interim period, it'll be the Hornady 375 parent casings.