Help! 357 mag question...

deadIce

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I got a S&W 686 in 357 mag, 6in barrel. I took it to the range the first time the other day. It fires the 38Sp rounds fine. But with the 357 mag, the hammer hit the primer so hard, it punched the primer right out of the casing :eek: . I was firing Winchester Winclean 357mag 125gr jsp.
This is resulting in a Large blast that escapes from behind the cylinder. I could feel the blast across my hands and on my face!! Not to forget the huge flames from the explosion coming out the side.
The question is, is this normal? I haven't owned a 357mag before and am wondering if this is how it is, or if I should take it by a gunsmith and have it looked at.

thanks.
 
Did this happen on just one round of .357? Maybe the primer wasn't seated properly and it was the powder that blew the primer out.......definitely isn't 'normal'.
 
I've got a 686 and have not seen this problem before. I would suspect soft primers otherwise you would have the same problem with the 38 special.

What ammo are you using?

I presume that the 686 is less than a -3 model
 
357mag.JPG

This is a picture of the round that had the primer punched out. I fired two more rounds of 357, the primer stayed in both of them but they are slightly ajar.

I fired 100rnds of 38sp with no problem. it does seem like the hammer is hitting the 38sp primers a little harder than i'm used to with my glock (in 40S&W), but they are still seated normally.
 
New ammo?

I'd say it is a problem with the ammunition... I'd contact Winchester and tell them what happened.

They might want you to send the rest of your ammo to them to inspect (or something like that).
 
Were the .38spec. loads really mild? I have heard of light-and-dirty .38 ammo causing a large build-up in the throat of the cylinder and causing pressure excusions. Never seen it myself; but possible, no?
Maybe next time you switch from .38s to .357s use a dry bronze brush to give the chambers a quick scrub, maybe a couple passes therough the bore too.
How does the inside of the frame look where the firing pin hole is? Nice and smooth?
 
A build-up of fouling from .38spcl will make it very hard to chamber .357 rounds. I've never seen it cause high pressure, especially this high. Check to see that the cylinder is timed right and inspect the bore. It sounds like pressure is really getting high. I would not fire any more of that ammo til you get this sorted out. Pick up a box of a different brand and try that. Or if you reload make a few of your own. Be very careful to go by the book when reloading .357,reduced loads can be dangerous. Keep us posted on your results.
 
I've shot that ammo lots out of my 686.......it's pretty hot. It's normal to have a pretty serious flame show out the muzzle and sides of the cylinder. Primers are usually flattened, but I've never pierced or blown one out.
Does your model have the firing pin on the hammer or is it the transfer bar type?
One thing that wear on magnum revolvers over time, and can be damaged by careless cleaning is the little hammer nose bushing......
 
CanadianPackRat said:
I presume that the 686 is less than a -3 model


Hi

You did not answer this question

586/686 and 586/686-1 are under recall. -2 and up are okay.

Swing out the cylinder and look at the frame to see the number. If you do have the affected numbers, look for a big M

If you have the M, it means it's been modified(fixed)

Sticker
 
I shot my 686 for the first time on Sunday. I've never fired .38/.357 before. I fired 158g .38, 125g .357, and 158g .357 out of it. The guy at Shooter's Choice said that the 125g was 'pretty snappy'. HOLY COW!!! I couldn't believe the difference.

Compared to the other rounds, the 125g .357 mag. was incredible.
 
I really think it's a bad lot of ammo where the primer wasn't seated properly, bad brass with a problem with the primer pocket, bad batch of primers or the powder charge got fubarred. Like someone has suggested here, call Winchester.....I've shot thousands of rounds through my 686 and have never had that happen with 'hot' loads.
 
Was the recoil any stronger with the cartridge in question compared to the other .357 magnum loads you fired? How about ejection? Did the fired cases come out easy or did they need some force to push the plunger?

I'm just wonderring if there was too much powder - I know they were factory loaded, but things happen, right?
 
Not to go off topic, but I played with a .357 back in Febuary. the .38's were great, But when i put in th .357's the fireball that occured was intense. And much louder everyone in the range stopped.

Kick ass Stuff.
 
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