WARNING - 4955

[Calvin45]

I will not be touching this powder with a 10 foot pole from here on out. Thank God they've discontinued this particular enduron powder, imr 4955. This stuff is downright scary. Freaking dangerous. Just wanted to beat a dead horse for y'all.

Got to do some shooting to test a bunch of different loads for velocity data.

I was shooting with my beloved old savage 99 in 243 Winchester with the old school Barnes x (not tsx), 75 grain, hbn treated.

I have never seen a powder go from mild cratering to a siezed action AND TOTALLY BLOWN OUT PRIMER over an increase of one grain of powder. Except with 4955. I gave it another chance after this exact same thing happened in a 300 win mag about 7 years ago…

I was taking notes and chrono readings - Winchester headstamps, fed large rifle primers.

45 grains - nowhere near enough pressure, sooty looking, very rounded primers, only 3140 fps. Went up to 49.

49 grains - no pressure signs AT ALL. 3452 fps.

50 grains. Slight cratering, no pancaking of the primer, no shiny spots on headstamp. Easy extraction 3469 fps. Note - only 17 fps change from 49

51 grains - case failure - wouldn't extract, had to "manhandle" the lever violently to get it open. Primer COMPLETELY BLOWN OUT THE BACK OF THE CASE. SOOT EVERYWHERE. And the real shocker: 3631 fps!!!!!

Went from very minor cratering to a failure to hang on to the primer over one grain increment. Increased 17 fps from 49 to 50 and increased 162 fps from 50 to 51.

WHAT THE HECK!!!!!

Any of you ever see anything like this ever?

Also again, fair warning, if you own this powder be so freaking careful. It's a disaster waiting to happen. I'm honestly shocked I haven't heard more about it.

Had nothing to do with the bullets, brass, gun…used the same bullets with 4 other powders and didn't see any funny business like this working up.

Just weird.

And scary.

 

[3chester]

Case too long maybe?

 

[asd9055]

I believe ALL Enduron powders have been discontinued. My thinking is, from pictures I ahve now seen is various forums, it was unstable on the shelf. But that is just my opinion. No facts

 

[Calvin45]

Case too long maybe?

I did wonder about that too but verified that it wasn't. Good thought tho.

As I mentioned, I had this happen once with a .300 win years ago and assumed I must have done something wrong. But it's never happened likenthis with any other powder in any other load where it goes from no tRouble to big trouble in such a short window. It's like someone who doesn't know how to give good instructions when you're backing a trailer or something haha

"You're good…you're good…keep going….oh shoot you hit someone's car…"

Except it's "you're good…you're good…keep going…okay you froze your action and popped a primer"

 

[Calvin45]

I believe ALL Enduron powders have been discontinued. My thinking is, from pictures I ahve now seen is various forums, it was unstable on the shelf. But that is just my opinion. No facts

Yeah I know they're discontinued and am not pleased about some of them. 4451, 7977, and 8133 are, or were, awesome and stable on the shelf in my experience. We've discussed this possibility in the past on other threads haha, I personally do not believe they were unstable based on two or three individual pictures or accounts on the internet. If they were unstable for real you'd be hearing a lot more chatter than that.

 

[asd9055]

I agree with you that people were happy with results with those powders. But I have seen a few pictures of different powders in three different forums where the lids dissintegrated. Necxt thing I knew they were discontinewed.
My thougt is, from experienced in other industries, if you stop making it, you don't admit fault/responsibility and can always blame it on other factors. If you recall it, you open your self up for more liabilty, Again, my way of thinking, no facts.

 

[cape cove]

@Calvin45
I had just about the same thing happen to me in my 7/08 with StaBall 6.5. In my case there was no cratering. All good then 1 grain more and blown primer semi frozen bolt. Hard to read pressure when there is no signs.

 

[Calvin45]

@Calvin45
I had just about the same thing happen to me in my 7/08 with StaBall 6.5. In my case there was no cratering. All good then 1 grain more and blown primer semi frozen bolt. Hard to read pressure when there is no signs.

Dang. Good to know. Saw some 6.5 staball at my lgs. Was tempted. But a little voice inside just said "don't" haha. I think it might have been @ButterBean speaking telepathically

 

[Koda_]

49 grains - no pressure signs AT ALL. 3452 fps.

50 grains. Slight cratering, no pancaking of the primer, no shiny spots on headstamp. Easy extraction 3469 fps. Note - only 17 fps change from 49

51 grains - case failure - wouldn't extract, had to "manhandle" the lever violently to get it open. Primer COMPLETELY BLOWN OUT THE BACK OF THE CASE. SOOT EVERYWHERE. And the real shocker: 3631 fps!!!!!

I thought velocity plateaus were a sign of pressure?

You went a full whole grain and only gained 17fps then jumped another full whole grain?

 

[Calvin45]

I thought velocity plateaus were a sign of pressure?

You went a full whole grain and only gained 17fps then jumped another full whole grain?

Yep. I've heard mixed things about plateaus.

As this was just for the purpose of finding velocities for different powders and then I'll fine tune the right one once I settle on it, I don't mess around with smaller increments than that. By no means a novice at this, loaded many different powders and bullets in about a dozen cartridges and this particular powder has now done this twice and all others I've tried have done it exactly zero times.

I've seen velocity plateaus that signified the existence of "nodes" waaaaay below max pressure as well.

But good point. I did find it a tad suspicious.

 

[Calvin45]

I will post my findings for this bullet and the five powders tried today in another thread. Just in case it's of benefit to anyone down the road. I know they haven't made this particular bullet for a long time…that's exactly why I want to share my data! If I still managed to get my hands on some there are no doubt others out ther haha, and I couldn't find any data for this one. You certainly can't just use ahy 75 grain 243 data for a solid copper with no relief grooves! The HBN treating did seem to be a good thing regarding fouling and evening out the numbers for the other powders. Dug Some of the bullets out of the snowbank they were fired into. Like what I saw. Good strong rifling, no sloughing off of the copper from the groove portion…and they opened up and shed their petals some haha.

 

[cape cove]

Did you ever run your load and particulars with Quickload to see what it says.

 

[Calvin45]

Did you ever run your load and particulars with Quickload to see what it says.

Don't have quickload, would be interested to know but also know that some of these new "superpowders" with the copper erasers, temperature insensitivity additives, multiple bases, progressive burn rates, etc… can be tricky to pin down for a burn rate. Don't always act the same. The older I get the more I'm rediscovering the merits of boring old single base powders haha.

Didn't get to the same velocity but old reliable imr 4064 behaved itself wonderfully haha

 

[Koda_]

Yep. I've heard mixed things about plateaus.

As this was just for the purpose of finding velocities for different powders and then I'll fine tune the right one once I settle on it, I don't mess around with smaller increments than that. By no means a novice at this, loaded many different powders and bullets in about a dozen cartridges and this particular powder has now done this twice and all others I've tried have done it exactly zero times.

I've seen velocity plateaus that signified the existence of "nodes" waaaaay below max pressure as well.

But good point. I did find it a tad suspicious.

What general velocity should a 75g bullet get from a 243 caliber rifle?