Help - ruptured primers

[savasyn]

Hi all,
I've been loading .44 Magnum for a short while and haven't really had any problems other than the one time I failed to heed all the warnings and downloaded(half a grain) some rounds with Win296 which resulted in ruptured primers. Needless to say, I promptly set everything back to 23gr of 296, which is the bottom of the safe zone with 240gr bullets and where I had been loading previously.

Today I look out a bunch of loads that I know were set at 23gr and eight of 60 rounds fired had ruptured primers again. Now I'm confused as they mostly work as expected but those eight definitely popped. As I understand it, the danger in downloading 296 is that you get a pressure spike due to uneven burning, so perhaps I'm not crimping enough and the bullet is moving too easily causing the same problem given that I'm running at the minimum load already.

I'm hesitant to up my load a bit in case that is not the problem and things get worse. I'm not seeing any signs of over pressure on the other, non-ruptured cases.

What else should I look for to help diagnose this problem?

This whole batch was loaded with the following components: new Starline brass, Hornady XTP 240gr JHP, 23gr of Win296 and Winchester Large Pistol primers. Press was a Dillon 650.

The only other thing I can think of is that this batch of brass might be bad. I've loaded hundreds of this recipe with used brass and never had an issue.

Any help would be greatly appreciated!

Thanks!

[wtkaiser]

If I were facing this, I would disassemble anything left over in that batch, put it back in the containers and start over again. I know nothing of Dillons. Also, you should always use large Pistol Magnum primers especially now with the weather getting cool. 296 is just re-packaged H-110, and I've always used magnum primers for it (although the Win LPs do say standard or magnum loads).
Could also be that your powder got wet somewhere along the line.
When the "downloaded" cartridges went off, was there any sort of a hangfire (delayed ignition of powder) or flat out misfire? I had some 7mm rem mag that I loaded with standard primers when I first started out loading, and the hangfires were rough on the old shoulder....
These are my first guesses, but I am NO authority on the subject. Keep us informed if you find anything

[Chief-7700]

Are you roll crimping the bullets?

[mrkubota]

check your firing pin too..... you may have eroded it to a sharp point from the previous primer failures.

[Pete1979]

Seating depth?

[savasyn]

Thanks for the responses guys!

I had not previously considered using Large Pistol Magnum primers as the Winchester ones say they are for normal and Mag loads. Worth a try though I guess.

The downloaded failures I'd previously experienced did not hangfire at all but they had an odd sound that alerted me to the problem. I did not hear that this time at all, they all sounded the same. The only anomaly today was one(1) round that had no noticeable muzzle flash which is really odd considering this powder coming out of a 2.5" barrel. I stopped and everything but didn't notice anything weird at the time.

Yes, I am roll crimping into the cannelure. I'm questioning if I'm rolling enough now.

As far as the firing pin being worn, one of the guns used was brand new, first time fired. Additionally the rupture happens at the edge of the primer and not at the firing pin strike. As a picture is worth a thousand words, here's what they looked like:



For comparison, here one of the non-ruptured ones:

[sequoia_nomad]

Wow. Maybe the flash holes are slightly blocked? That's an odd one.

[Dark Mod]

I understand this underloading problem is quite common with W296/H110, and is almost as dangerous as overloading. If your seeing pressure signs i would definatley start making changes, if your at Min load i would just try working up a new load, maybe shoot for something in the middle.

Adjusting the crimp probably will help too but since its not an exact science id find a more scientific way to stabilize pressure using more powder

[ojisan]

I would look and see if there is a burr or something somewhere in the primer feed that is gouging the primer.
Maybe pop out one of those holed primers and check it to see of the hole (crack?)goes all the way down the side of it.

[Bill Steele]

I have loaded thousands of .44RM with Winchester LP primers and never seen anything like what you are experiencing. I do have to say, the WLP cups are not the hardest around, not as soft as Federal, but on the softer side for sure.

I have downloaded H110 below book levels and gotten very poor results (erratic velocities, unburned powder, etc.) but have never seen anything that looks like over pressure signs. I believe the admonishment from Hodgdon to not download H110/W296 below 3% of book levels is more from a poor burn result standpoint than some of the urban legend stuff about flash over, pressure spikes, shaped charge effects, etc.

I would give Olin a call and see if they have any ideas why their primer cups are failing. I bet they would want to know about your experience.

You might also give Hodgdon a call and see if they think downloading the W296 could cause this problem.

One final area I would check is to see what the flash hole looks like in the rounds where the primer failed, compared to brass that has not given you problems.

[kurac]

The only thing I would check would be to see that the brass was full length sized before loading and that the primers were seated below flush.

[savasyn]

I would give Olin a call and see if they have any ideas why their primer cups are failing. I bet they would want to know about your experience.

You might also give Hodgdon a call and see if they think downloading the W296 could cause this problem.

Not a bad idea, once I have some time during the week I'll give that a try.

The only thing I would check would be to see that the brass was full length sized before loading and that the primers were seated below flush.

Yes, they were definitely sized before loading. I run them through my Dillon so they go through all stages in the press.

As far as primers being seated, I suppose it possible that these weren't fully seated. I loaded about 200 in that batch, so it's possible a handful didn't go all the way in. I do check every round after loading to make sure nothing is obviously wrong and high primers is something I check for. Perhaps these were flush but not actually fully seated in the pocket.

I'll go through and check the remainder of this batch just to cover that base.

[savasyn]

I have loaded thousands of .44RM with Winchester LP primers and never seen anything like what you are experiencing. I do have to say, the WLP cups are not the hardest around, not as soft as Federal, but on the softer side for sure.

Are CCIs harder than Winchesters? I've only used WLPs but can get CCIs locally as well.

[Bill Steele]

Maybe just a bad batch of primers?

Are CCIs harder than Winchesters? I've only used WLPs but can get CCIs locally as well.

Yes, CCI and Wolf are harder than Winchester.

But honestly I have loaded Winchester primers in .44 loads hot enough that the primers flattened like sequin on a woman's dress and never had one split like you are seeing.

[Sheldon]

It maybe just be a bad batch of primers with faulty cups.