Home Forums Reloading Big Game Rifles Primer leak question

Is a primer leak always caused by excess pressure? I had a rifle rebarreled to 6.5 creedmoor so I've started handloading for it recently. I used noslers data to work a load with 130 accubond. The max load for H4350 is 43gr, fed 210, 2865 fps with 24" barrel. I have a 22" barrel and it took 42.5gr, 210M primer to get an average of 2740 fps. I bumped the load up to 42.7 gr, but switched to WLR primers and the avg was 2775 over 11 shots (2760-2789). Out of the 11 shots 2 primers leaked/pierced, I've never had this happen in 16 years of handloadinig and I didnt think I was getting into over max pressures. I just recently upgraded from an old shooting chrony beta to a prochrono. The other 9 primers look "normal" to me. Could the primer switch have caused a pressure spike. I think the velocities are accurate because the groups at different distances are close to my ballistic program. Both the primers have pin holes near the edge. This was the 4th firing on this brass, some had heavier charges than others working loads for different bullets.

It could be the primers, there are some bad WLR lots out there.

Bad Winchester primer lot numbers as collected by John Barsness:

CLL555G
DAL594G
DFL717G
DHL766G
DNL 837G
DNL836G
EAL234G
GDL225G
GEL250G
CAL401G

Mathman
thanks, I just checked and my lot # is EAL018G. When I first got the rifle back I ran a box of the federal match 140 amax ammo over the prochrono and it avg around 2650 from the 22" and its rated at 2700 from 24" so I have some confidence in the prochrono.

I have had a few of these primers leak and not with high book loads.

When using CCI i have not had this problem.

Lot numbers?

Yup, it's your Winchester primers. I have about 5K of WLR that do this, no other brand I've used does it. Will have to check on the lot number.

It's different than a loose primer pocket; if you deprime them and look closely, you'll see that the leaking primers are actually cracked up the side of the cup, and high pressure gas leaked through the crack.

When I ran into this with WLP primers in the 10mm a few years ago, Winchester sent me a gift card to buy more Winchester primers. I've encountered it enough with different lots though to wonder if it's common to all Winchester large primers, regardless of lot #.

Yondering,
you are right. I deprimed then cleaned the cups up with some steel wool and there is a crack running up the inside to the pin hole. Now the question, is the crack caused by excess pressure or a problem with the metal. I dont think that load is above max safe pressure at 2775 fps in 22" barrel. I think its approaching it but shouldnt be above.

I had primer leaks such as those pictured in .30-06 loads for an M1 Garand that go about 48 to 49 Kpsi.

They did not leak in the .45-70 loads I had put together that were loaded to the 28 Kpsi region, but I changed them out.

Now the Standard Deviation in those loads have went to hell with the new primers I used.

I suspect the material for the primer cups was not propery annealed prior to forming.

Winchester's displayed some real shoddy QC as of late, with inconsistent brass and leaky primers.

I wonder how they've been doing with the QC on their powder and bullets?

Now I have 2 divots in my bolt face from the leaks so I think I will avoid this lot of primers. I bought 300 of them and only part way through the first pack. I'll go back to the fed 210.

I had the same thing with some "starting" loads in a . 270 and WLR's. I tried some even lower charge weights and still got those little pinholes. About that time I started seeing other reports of primer leaks so I finally figured out what the problem was. I was really questioning my reloading procedures 'til then.

I have had a similar problem w Winchester primers. Haven't had it happen with fed or CCI primers. No more winchester primers for me.

Last year I had primers that looked exactly like that. WLR large rifle. Mine were not on "list", but I sent them back to Winchester. Stress cracks. They paid for a new bolt and new primers. Mine were starting loads.

I had Winchester primers do the same to me in the fall.

Anyone who had this problem please post the lot number if you can.

I've still got about three thousand WLR primers, but damned if I'll use them. Not listed lot numbers but I'm not going to take the chance again.

The lot # from the ones I had: DAL594G


Thread:

http://www.24hourcampfire.com/ubbthreads/ubbthreads.php/topics/9603533/What_causes_this?#Post9603533

I had similar problems with Winchester primers cutting my bolt faces. Winchester has yet to pay for any of my damaged bolts but sends me a "coupon" to replace the primers once I send them in. Unfortunately I purchased the primers when the "shortage" was in effect so was stuck with the amount I purchased. I still need to go through them and see if I have any of the bad lots or need to add a few to the list.

lastaround,

The list of lot numbers is by no means comprehensive. It was what resulted from a Google search of reports on the Internet.

The one thing the search did NOT find was any similar reports of leaky Winchester Small Rifle primers.

So about what vintage are these leaky primers? I ask because I stumbled on a pretty good stash of Winchester primers, 35k to be exact. All of mine are the old orange and white boxes. I hope they were produced before things went south.