Pierced Primers W/29-2

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My 29-2 (bought new in '75, fired maybe 10K rounds) pierces primers, about 1 in 50. I have replaced the firing pin (hammer nose, IIRC) as it had a little crater in the tip, probably from the hot gas. Back to the range, same problem. This happens with whatever load I am using; 231, Trail Boss, Unique or 4227. CCI 300 or 350 primers, as appropriate.
I don't load super hot, usually 1000-1100 FPS.
Talking to other 29 shooters at the range, they say it never happens to them.
Any ideas?
Is this something I could maybe fix, or does it need to go back to S&W?

primer.jpg
 
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Maybe this should be in the reloading forum, but I'll offer my thoughts on it here.
I have had similar trouble lately with some CCI primers, which was a suprise to me since they have notoriously hard cups compared to some others.

I don't know which primers you are using, or how long this has been going on with your gun/loads, but with all the shortages that have been going on, and the fact that alot of guys everywhere are having trouble with certain components, and ammo like .22 LR ammo, I have to wonder if it is related to the QC of some of the companies right now who are rushing to meet the demand.

One thing you may try is to expose the firing pin tip, and polish it lightly with some 600 grit emery cloth to remove any small burrs that may be there.
 
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Nothing that needs to be fixed, just use different primers. It is a matter of ductility, or lack thereof, due to the metal being too hard. Same happens too often with Remington frequently. I have never had a pierced primer in many thousands of Winchester and Federal, a few hundred with Remington, and haven't used any CCI for over 40 years.

From the one on the right there is some erosion on the firing pin caused by gas leakage through the primer. Polishing the pin tip will help how it looks, but won't affect the primer failures.

To be strictly correct, that is not a "pierced" primer, it is a cracked one. There is definitely no issue with pressure in that load.
 
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Pierced Primers??

My first step would be try Mag primers on your next 100 loads. You may want to back down your charge a little, although I don't think that it would really be necessary. Powder Valley has Wolf Large Pistol Magnum for I think $25.50 per K + HazMat +shipping. It pays to bulk order, to make the most of the HazMat fees.
I load mostly 2400,H-110, and WW-296, and use Mag primers in all loads. I shoot a Ruger SRH, and have no primer problems with Wolf.
A word on Wolf--be sure to FULLY seat all primers. On some brass they are tighter than WW or CCI.
With the looks of your fired cases, to me it looks like too much main spring pressure?? I would think you may take a screw driver to the range and try backing off of the main spring strain screw 1/2 to 3/4 of a turn on your next trip out.:)
 
Hmmm curious!

I've loaded probably 6000 - 7000 rounds over the last 6 months

I've used what ever brand of primer I could get my hands on, CCI, Fed
& Rem and I've never seen "pierced" or "cracked" primers.

I wonder if the caliber has anything to do with this. I load .38 spl & .357 mag.
 
The illustrated one is a CCI 350 Magnum primer. Had the same with CCI 300s and Federal LPs. This is leading me to believe there's a problem with the gun, that's why I posted here instead of reloading forum. I'm using the same reg. primers in 45ACP and 44 Special and have NEVER had one fail in 1000s of rounds in those applications.
 
If there are no issues with the hammer nose bushing itself, I would look at the length of firing pin protrusion thru the bushing when fired, especially if this is a new firing pin, rivet, etc.. Incidentally, you did re-install the hammer block correctly when you had the gun apart to repair the hammer-correct?

:)

Bruce
 
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Do NOT feel alone. I have seen this with different firearms with less then hot loads over the years (.38, .40. 45 ACP). I am not going to say "don't worry" because I do not fully understand it myself. But. I have chronographed rounds that exhibited this piercing along with rounds that did not and there appeared no difference in velocity or accuracy and no signs of pressure (can't afford strain guages).

That said, I do not figure it to be a firearm problem or a load problem but, rather, a primer hardness variation....?

WILDPIG
 
I'm with BruceM on this one.

Check firing pin protrusion.
 
I'd double check the bushing myself. The 586 had problems with that the led to a recall on the series.
 
That does look like a rather deep firing pin indent. One thing sometimes overlooked is cleaning primer pockets occasionally. You mentioned around 10K rounds fired. If you use the same brass and is reloaded many many times without cleaning the primer pockets there can be (and usually is) a build up of crud in the primer pocket and this can cause the primer to not seat all the way. Not sticking up so far it would cause binding, but enough to cause deeper firing pin indent. So if you have a lot of older brass you are reloading, and haven't cleaned the pockets recently, check that possibility.
 
High primers ahouldn't an issue. I also load for an M1, where high primers are %^$@$#, so hand prime and inspect each one. I have about 600 cases now and rotate them also.

I have always kept the mainspring adjustment spring tightened all the way. I'm going to back it off some (maybe 1 turn?) and see if that lightens things up.
 
If there are no issues with the hammer nose bushing itself, I would look at the length of firing pin protrusion thru the bushing when fired, especially if this is a new firing pin, rivet, etc.. Incidentally, you did re-install the hammer block correctly when you had the gun apart to repair the hammer-correct?
Bruce

Thanks, Bruce. Hammer block seems OK. Is there a specification for firing pin protrusion? I'll measure it today.
 
The mainspring screw is supposed to be tightened all the way. Do not back it off. That may only lead to misfires on the "good" primers.

I think Bruce may have given you a good place to start. Check the firing pin protrusion. You may have just gotten a gun with one longer than spec for your model. That is a relatively easy fix if that's the case. If you don't have any way to measure it, take it to a gun shop that has a model very similar to yours (N frame of pre mim design) and check it against that one.
 
If I weren't on the road I would check my manuals for you. If you live near a decent sized book store see if they have Patrick Sweeney's gunsmithing for pistols and revolvers there. I seem to recall it having the firing pin protrusion specs listed in the smith and wesson chapter.
 
As close as I can measure the 29-2's firing pin protroudes .050". For comparison, my 14-4 that's never pierced a primer measured .055".

The bushing in the 29 appears to be ever so slightly recessed, not flush like that of the 14, which has seen MUCH less service.
 
Yep, the firing pin indents look especially deep. Generally, if the hammer nose bushing is set back into the recoil shield, the primers will extruded back into that recess, making it difficult to open the action. So, while it's good to check the bushing, the firing pin protrusion seems really long.

Bruce
 
I had this problem with my Ruger Super Blackhawk back in the late 60's and cured it by using Rifle Primers. They have (i believe) a thicker cup. End of trouble forever. No mods to gun.
 
I had this problem with my Ruger Super Blackhawk back in the late 60's and cured it by using Rifle Primers. They have (i believe) a thicker cup. End of trouble forever. No mods to gun.


That may work in some guns, but rifle primers are hotter and can raise pressures to dangerous levels, not to mention that they have a deeper cup, and may not seat al the way home, whivch in turn can cause high primers. That isn't something to be taken lightly! If a primer is high, and gets set off while the round is not in alignment with the bore.......:eek:
 
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primers

had a 25-5 that did the pierced primer thing. backed the strain screw off a bit and end of problem. since then, i shortened the screw a little and haven't had any problems-about 20 years and 3 or 4 thousand rounds
 

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