357 Sig help

R

rifleman0311

New member
I've had zero issues loading 124 gr but I recently bought some 147s and I'm having issues. I'm using a Hornady lock n load with 147 Rocky mountain reloading
7.5 gr 800x, 1.135 OAL, Winchester primers, mixed brass. Data pulled from Lyman 50th......out of 25 test loads 3 did not fire. They chambered but the trigger felt dead and mushy. I've never had this happen on reloads before. Attempted to fire all three and one of the two had light primer strikes on the primer, the other two didn't show the primer even striking, nor would they have because the trigger didn't seem to even initiate the firing pin. Thoughts?
 
Overcrimping .357sig with the FCD can cause case deformation resulting in some rounds that do not chamber. Compare the dimensions of the problem rounds with standards.

.357sig has unique intricacies. I found it best to flare as little as possible, not at all with some bullets and “crimp” even with the FCD only enough to remove that flare. Overcrimping can actually cause the neck to bulge away from the billet, reducing rather than increasing bullet hold.

Can you manually chamber and fire those rounds? I don’t have my 49th handy but Hodgdon shows 9.0 max load under 147gr. It could also be that 7.5gr isn’t cycling fully. Enough to eject, but not enough to get the slide all the way back so it’s got full momentum to chamber the next round.
 
I'm aware of the light flare, I tend to do as little as possible. All rounds passed the plunk test in my barrel and chamber fine. Could the primers be seated too deep? Thanks for your reply
 
Do the fail-to-fire rounds pass the plunk test?

What gun are you using?

Light firing pin hits could be a gun problem. It might be anything from the gun not being fully in battery, to a dirty firing pin channel.

Can't really seat primers too deep, unless the primers are short and the pockets too deep (and this is in extreme cases), but even then most all firing pins/strikers will be able to reach them.
 
Are you sure your pistol is going completely into battery?
First, I would look at the bullet seating depth. Some bullet styles have to be seated a bit deeper to avoid prematurely engaging the rifling and thus preventing the pistol from going completely into battery.
I would suggest buying a gauge instead of plunk testing. They only cost around $20 and will show you more than a plunk test will. For example, a plunk test may not reveal a bullet seated a hair too far out.
Also, I would never expand or crimp this round. I’ve had my best luck by simply putting a light chamfer on the case mouth and relying upon neck tension to hold the bullet in place. If you are worried about bullet setback, you could use a slower powder that fills the case more like AA#9. I’ve not been bothered by setback though, even when I load with faster low volume powders like Bullseye.
Good luck.
 
could be the firing pin, could be primers might be seating deep(doubt it), could be GSR scale inside the brass or polishing media plugging the primer hole.

I prefer CCI 500 primers myself used to use Winchester in the past.

Hey - I've got some .357 sig brass I can't find anyone to trade me for - got any .40 brass you're not using?
 
Attempted to fire all three and one of the two had light primer strikes on the primer, the other two didn't show the primer even striking, nor would they have because the trigger didn't seem to even initiate the firing pin. Thoughts?
Click to expand...

I'm no expert but that is one of two things . Either the gun is not in full battery or you have a trigger/firing pin problem . I don't see how you can have the gun failing to drop the hammer/let go of the striker and it not be a firearm issue . Now it could be the reloads causing the failure but again IMHO that would be causing the gun not to go into full battery .

Another thought and I'm not sure because I don't load the round but did do a lot of research on the 357sig because I want one . Is it possible you are right on the edge of to much crimp so the cartridge passes the plunk test by stopping on the case mouth . How ever when the slide slams home loading the cartridge . The case mouth gets pushed in deeper and the case is now headspacing off the shoulder creating to much head clearance ?? even that would not account for the trigger not working properly . In that case you should still feel and hear the trigger letting go and the click ??
 
As said already:
Clean fire pin channel
Use a good case gage (your barrel is pretty good for this, except for headspace.
 
Actually, it’s been long since proven that almost all .357sig ammo/guns actually “headspaces” on either the shoulder or, commonly, the extractor. Indeed, very many semi-auto handguns of all calibers actually headspace on the extractor.

We had a thread on it a few years back. I don’t think anyone who commented had a chamber short enough (or cases long enough) to headspace “correctly”. Searches on other sites will confirm the same with their guns.

The SAAMI standard indicates headspacing in the mouth, but I’m not sure there’s a factory gun made that does it.
 
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Brian , that's been my understanding as well except the part that the cartridge never headspaces off the mouth . I always thought you could choose which one you wanted to use . Interesting concept though , not to unlike shooting 40S&W in a 10mm I guess ??
 
357 SIG head spaces where

Where the 357 SIG headspaces is a hot button topic. I kinda go with the case mouth. This is contrary to what appears to be common sense. I'd look to COL and possible problems with the case mouth. The assumption here is the dies are adjusted correctly. It's possible to cut to the chase with a case gauge. My gauge is a Wilson that came from Dillon. The ker-plunk could be deceptive with a bottle neck cartridge that headspaces on the case mouth. I use Lee Sizer and bullet seater. The taper crimp dies is a Dillon. On all this YMMV. A hot button topic. Right on a minimum bell on cases. My handguns were a SIG 229 and a G23 with OEM barrel in 357 SIG-my everyday carry.

Addendum: I'd not fiddle with mixed brass in a high pressure cartridge personally. My brass is Starline. Also get a bunch of Winchester. May be good to see what head stamp is on the misfires. I never mix brass anyway.
 
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Metal God,

Theoretically you can choose. In reality, I’ve never seen a .357sig case long enough to reach the “mouth” of the chamber. My own personal experience is limited, only 3 barrels, but others have verified with the same results.

Easy enough to verify. Simply measure your barrel from the back of the hood to the chamber mouth and then check the length of your sized cases. You almost certainly not find one long enough to reach.

There's also no real debate about the original design. Some years ago I had an email from SAAMI about it. The cartridge *was* designed to headspace on the mouth. I'll see if I can dig up the email.

edit: I found the posts about it. I actually *called* SAAMI, not about the .357sig but about the term "case headspace", about which there was a debate. In that conversation, the SAAMI guy was absolutely adamant that the sig round is designed to headspace on the mouth. He was a little unpleasant about that particular fact and curtly informed me to "check the diagrams". In reality though, it's impossible for the vast majority of chamber/case combinations. Fact is, most guns don't headspace on the shoulder either, unless the reloader intentionally sizes them to. Most semi-auto handguns of all caliber/cartridges actually "headspace" on the extractor.


In regards to the OP, the more I think about it, the more it sounds like a gun problem. I can think of no reason that anything with the cartridge itself would cause the trigger to be "mushy". Being out of battery might prevent firing, but the trigger wouldn't just feel mushy.
 
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Headspace on the extractor? Wilson 357 SIG gauge.

Extractor: The best example of this function is with 45ACP. I found this out measuring once fired 45 ACP brass. Most of it was too short already. Figured this related to having the gun go off with anything that chambered.

357 SIG. Look at the Wilson case gauge if there is any doubt where the cases "headspaces." There is a step on one end and the case must be on a flat surface. What is the right term instead of "headspace."
 
Let me ask this then . Is it just assumed it's headspacing off the extractor rather then the shoulder . As I said I don't load the cartridge but do load several bottle neck rifle cartridges . I can't think of one where the extractors tolerances are so tight that the extractor catches the case before the shoulder bottoms out in the chamber .

When loading for bottle neck rifle cartridges , generally speaking you don't want the case sized from head to datum point . To be sized more then .005 shorter then the head space of the chamber . Now I've seen cases sized as much as .012 shorter then the chambers headspace but even then that seems like a pretty small amount of allowable variance from which the extractor can operate within to accommodate all firearms and ammo cases ?

How ever we are not talking about a cartridge that is supposed to headspace off the shoulder so maybe "If" the 357sig "is" headspacing off the mouth there is a large gap/clearance between the case shoulder and the chamber shoulder by design which would result in the case headspacing off the extractor if the case is trimmed to short and the chamber is to long ahead of the shoulder . It just seems like the natural next stop for the case after the mouth would be the shoulder and not the extractor ???? This in no way means it does or should just that it seems reasonable to conclude .
 
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J.G. Terry said:
What is the right term instead of "headspace."
Click to expand...

Ironically, that was the purpose of my call to SAAMI. There is no official term for what is commonly called "case headspace". SAAMI uses an alpha-numeric symbol that looks more or less like a railroad crossing sign to identify that dimension.

Metal god said:
Is it just assumed it's headspacing off the extractor rather then the shoulder .
Click to expand...

In general, it would be an assumption, but it has been measured in many chambers. Much like a bottleneck rifle cartridge, the sig round CAN be resized so that it headspaces on the shoulder. However, this requires intent on the part of the handloader. Most folks who are loading handgun cartridges do not make such measurements. Usually, the die is adjusted in the press to touch the shell holder, or even "cam over" on some presses. If the sig die is set up this way, it will almost always set the shoulder back far enough that the case will "bottom out" on the extractor before the case contacts the chamber.
I suspect that the same thing would happen with many bottleneck rifle cartridges although I've never tried. If the case was sized as far as the die could size it, as is the normal practice with handgun rounds, a great many rifles would also "headspace" on the extractor.
Additionally, since "bumping" the shoulder less also shortens the neck, there is some danger of reducing the already tenuous neck tension of the sig. I found this to be the case with my barrels.
 
Thanks for the replies everyone, so I checked the rounds again...they passed the plunk test however I didn't even realize on the range none of the three allowed to pistol to go into battery. How could 3 out of 25 fail to allow the pistol to go into battery when the majority of them did? Where should I start adjusting dies? Resizer?
 
I would start by measuring the suspect rounds to find out where they are out of spec. I go back to my original suspicion that the FCD is buckling the case. I’ve had it happen.
 
Case Gauge may be a good idea

Case Gauge may be a good idea: I have a strong feeling about case gauges. These gauges help identify problems in the early stages. In my case a 357 SIG is my carry gun. Normally, the gun is loaded with factory cartridges. However, reloaded cartridges are carefully assembled. As a result reloading equipment is used conservatively. This includes the Wilson Case Gauge. Gauges are also used with 9mm, 40S&W, 10mm and 45ACP. Voodoo reloading techniques on potential defense loads leave me cold-possibly literally. :eek:
 
rifleman0311 said:
Thanks for the replies everyone, so I checked the rounds again...they passed the plunk test however I didn't even realize on the range none of the three allowed to pistol to go into battery. How could 3 out of 25 fail to allow the pistol to go into battery when the majority of them did? Where should I start adjusting dies? Resizer?
Click to expand...

One more time: what gun are you shooting? We need all the information you can provide to help troubleshoot the problem.

If the rounds that failed to fire passed the plunk test, the next question is why they didn't chamber at the range. This suggests something was in the chamber that prevented them from going all the way in - or prevented the slide from going all the way forward.
 
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