Recently I was sighting in for some factory loads Winchester Supreme 357 mag 180 grain gold partition in my S&W 686 and was pircing the primers on a few rounds out of 15 rounds fired 4 had pierced primers and the rest were flattened extensively some to the point of not being able to tell where the case stopped and the primer started. I stopped shooting the rounds and cased the firearm until I could figure out what was happening the firearm was extensively cleaned prior to range sesson. Eirlier in the life of the pistol about 8 years ago I experienced the same prob with some federal loads but realized that the cause was leading in the barrel due to shooting cast loads since then I have not used cast bullits. What could the prob be? is the wichester loads no for use in revolvers but made instead for the lever guns? or maybe I have a timeing problem with the cyl? to add info the 686 is a -4 model I was fireing single action as I was zeroing my 2x scope for hunting thanks James

the rest were flattened extensively some to the point of not being able to tell where the case stopped and the primer started............

That is a sign of VERY high pressures.......I'd quit shooting those loads.

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NRA Instructor

That's pretty serious as it's a sign of excessive pressure and I'd be contacting Winchester about because that is not suppose to happen to factory ammo. I'd also check the gun to see if the barrel and is excessivly fouled which can cause an increase in pressure.

What the gents already said.
Don't even let those loads in the same room with your gun.
Call Winchester and by ALL means, hang onto the spent brass. Does the box indicate a "lot number"?

I have some Aguila .357 ammo, that is like that. I will not shoot anymore of it.

If you had problems with the gun before and tracked it to shooting "cast bullets", I'd say that you have maintenance issues. It would take a huge amount of bore fouling to increase pressures in safe handloads to the point where they surpass flattened primers and go all the way to pierced primers. Of course, then again, the problem may not have been the bullets but rather the load or a broken firing pin or other mechanical problem. Does this gun have a frame mounted firing pin and/or is it one of the earlier 686's which was recalled because of the hammer nose bushing issue? I don't think that the 686-4 was part of the recall.

It would be very risky for the big W or anybody else to make pistol caliber ammo which is only safe for rifles so I doubt that's the problem. Also, loads which are that far above max pressure are usually EXTREMELY difficult to extract. They almost have to be beaten out of the cylinder with a dowel and hammer.



Bruce

Not sure on pistols but if you pierce a primer on some rifles, you need to replace the firing pin. The hot gases etch/sharpen the firing pin which causes more pierced primers.

It would be interesting to know if you have maybe a partial box or other ammo that you know has not had this issue available. If so when you fire this "known good" ammo what happens?

Temperature, Has the ammo that is doing this been placed somewhere very warm just before firing? such as on the dash heater vent or somewhere similiar ?

Firing pin nose smooth? or is it sharp or burred? sometimes they will seem smooth under the finger tip but if you drag your thumb nail across or around it you will find it scratches the nail surface.

Did you buy this ammo from a reputable place such as that it would be unlikely that someone swapped out ammo that was reloaded?

Good luck in your finding the fault of the issue

-2Sigs

Crud in the cylinder can cause setback issues and result in unusual primer readings. If you've been shooting a lot of 38spl, be sure to ream out any buildup in the charge holes. Regular cleaning won't always get it.

Hello James,

I would tend to agree with BruceM. In parallel to contacting Winchester, I would have the 686 inspected by a gunsmith. If you have seen the issue before, it think a visual inspection by a gunsmith you trust is worth the money. Perhaps contacting the S&W support people would also help. Safety is paramount is your particular case, specially with higher pressures of .357.

Good luck,

Guy -