Holey Primers in 357

[shell70634]

357 mag brass assorted brands, 125 gr JHP, 8.5 grains Unique, Remington 1 1/2 primers, velocity between 1150 and 1250 depending on which revolver i used.

Some of the primers were broken through by the firing pin. I used a model 19, a model 66, and a model 28. Didn't happen all the time. Didn't have any signs of overpressure.

Any ideas about the cause? I don't believe it was to hot. Maybe primer seating depth due to assorted brands of brass? It was a fun load but I'm just a little concerned. The holes were just large enough to make the crater black.

 

[P95Carry]

Well - all the revo's if earlier ones will have fixed FP - and I have had this occur with my M27 and M19 before.

Rem primers IIRC are sorta middle ground compared with hard CCI and soft Fed. I think with your loads, which are hardly full house, the problem is perhaps no more than the rapid primer set back against an FP which is still in fwd position briefly - before it retracts with trigger reset. The primer can of course only set back so far before recoil shield stops it, and then case rearward movement too pretty much ''reseats'' the primer.

I would not be overly concerned as you don't mention flow and cratering which as you know would indicate a lot of pressure and Unique is not that fast of a powder in that loading IMO to give any pressure problems.

I certainly have had it happen over the years - but in these guns do not let it concern me.

 

[tc300mag1]

You said the hole is just big enough to make the crater back how big is the crater.. pic per chance?

The load isn't a stout one so i don't thing it would be over pressure

 

[shell70634]

The holes are very very small. Just large enough to allow gases to make just the firing pin indentation dirty. Not overly deep. And none of the revolvers I fired them in have ever had this happen before. The brass is a mixture of nickel plated 357 mag. Don't know how many times they have been reloaded, but most are once fired by me.

I forgot to mention that i fired 100 rounds and probably had 20 with holes. That was the last of my Rem primers. We shall see if CCI does the same.

 

[tc300mag1]

It could very well be ya had some thin primers i don't use rem primers myself i use wither cci or winchester

 

[P95Carry]

Shell - so a 20% effect rate. But if holes real small then even more certain no pressure issues.

I used up my Rem 1 1/2's a while back but forget whether any issues. The CCI's will for sure be harder and like as not stop this from happening. I do tho if choosing, prefer to see this effect now and again, than suffer light strike effect and no ''bang''!!!

I can't see your brass choice having much bearing on this really.

Report back later when CCI's are in the frame.

 

[mc223]

I shoot a Ruger Gp 100 in 357 and had similar occurances with small pistol primers. The fix: Started using WSR primers.

 

[BluesBear]

Small rifle primers in handgun loads?

I certainly hope you are working your loads up very very carefully.

 

[mc223]

Same type and quantity of compound, just a thicker cup. Work just fine with good tight crimps. I do not use match or magnum as they could push the powder columb and projectile into the barrel without ignition. Which could be a problem.

 

[Bad Flynch]

This is a well documented problem and was mostly dealt with years ago. The older style primers, e.g. Rem 1&1/2 have very thin cups and will burn through with magnum cartridges. They were designed to work with .38 Special class cartridges. The small rifle were designed to work with the .22 Hornet and .218 Bee class cartridges (low intensity). The same thing happens with Remington small rifle primers (6&1/2, I think) and the .222/.223/.222RemMag series of cartridges.

Nothing is really wrong with the load, the primers, or the firearm

The solution was to produce a new small pistol primer and small rifle primer that had thicker cups that would not burn through. Remington produced a couple of new numbers: maybe 5&1/2 for pistol and 7&1/2 for rifle. These will not burn through. All one needs to do is get the right primer for the job and quit worrying.

Hope that helps.

 

[BluesBear]

I do not use match or magnum as they could push the powder columb and projectile into the barrel without ignition.

Let me me see it I've got this straight.

You think a magnum primer could push the bullet AND the powder charge far enough into the barrel to creat a blockage without igniting the powder.
But you think a standard primer would not push the same bullet/powder combination yet would still ignite the charge?

 

[mc223]

Yep. When using rifle primers in pistol loads. Could happen once, which would be exactly one time too many.

 

[shell70634]

Thank you all for the info.