Going back to an M&P!

[Georgian]

Hey yall. Back in December, I decided to try the P320 Carry, my first and only Sig. I fell in love with the gun, it is accurate and easy for me to shoot well. I shoot quite a bit of steel case 9mm, and have quite a bit on hand. I expect any handgun I own to be able to shoot it in an emergency and at the range. The P320 ran the steel case at first, but over the last few months, it has began to completely choke on steel. Although I ensured the extractor and it's components were consistently cleaned, the P320 no chokes on every other round of steel and fails to extractor every time. I installed a Lone Wolf extractor hoping this might solve the issue, but it did not. I also ordered completely new extractor parts from Sig to replace them all, but decided I no longer trust this gun with my life and do not believe sending it back to Sig would solve anything, as they will only tell me not to run steel.

As a result, I made the choice to go back to an M&P, as the GEN 1 and 2.0 I've had over the years never malfunctioned with any type of ammo I ran through them. I now have a M&P9 2.0 FDE with the Truglo FTX sights on the way and plan to provide a complete range report.

 

[Saudade]

Plenty of people shoot steel through their 320s without issue. Perhaps you should ask in a Sig specific forum. I have a 320 Compact, a few M&Ps and other striker pistols. I never run steel in any of them.

Nice pickup on your new M&P and Welcome.

 

[Georgian]

I have attempted to diagnose the problem with other Sig owners, and none can offer any insight other than don't feed it cheap ammo. That argument does not hold water with me. I understand that steel case ammo is looked at as been lower quality and in the past maybe it was. I have shot case after case of the stuff and have seen good accuracy and reliability with it out of Glocks, M&Ps, Rugers, and even SCCY handguns; some people believe it is dirtier than other types of ammo, but I personally have not seen that. When I have to pry a stuck casing out of a handgun with a reputation like Sig, something is wrong. Some people may be able to live with the fact that their gun runs fine only with brass or they only intend to feed it with brass, but if I need to use any kind of ammo in an emergency, I want to be able to depend on my gun cycling that ammo.

 

[OldGoat]

Steel based shells whether handgun or shotgun can and do create cycling problems! The trapshooting forums report lots of extraction problems with steel based shotgun shells and I can testify I have, too. Apparently, steel cases expand and/or corrode barrel chambers in such a way that they cause cycling/extraction problems. Loose/oversize chambers seem to tolerate steel cases better for the most part. Polishing and/or lightly honing out troublesome chambers seems to help.

 

[Boxer9]

I don't shoot steel case in anything. I don't shoot aluminum in anything either for that matter.

You only run cheapest gas in your car or motorcycle? We aren't just talking about price here.

 

[Georgian]

I've never had any vehicle I've ever owned break down from 87 octane, but then again I've never owned a Cadillac. I wouldn't call the P320 a Cadillac needing high test, just a combat handgun that should feed within reason anything that is SAAMI spec or factory built ammo.

 

[Ruger Nut]

I've never had any vehicle I've ever owned break down from 87 octane, but then again I've never owned a Cadillac. I wouldn't call the P320 a Cadillac needing high test, just a combat handgun that should feed within reason anything that is SAAMI spec or factory built ammo.

I shoot A LOT of SCA thru my P320 without a hiccup. And, it's only 3 months old. You should send it back to SIG and see what the problem is. It can't hurt anything.
As a matter of fact, I shoot SCA thru my Rugers, Glocks, S&W's, etc. And, I have no problems with it in ANY of them. I even shoot SCA thru my AR-15's. SCA is no dirtier than any other brass ammo.

 

[Georgian]

I initially intended to send it back to Sig, but I read an article reviewing the P320 Carry and their test gun wouldn't run steel out of the box. Here is the article: Sig Sauer P320 Review and Dirt Test [2019]

I contacted the author of the article and asked if they ever contacted Sig about the matter. He said he was told that the official company stance was not to use steel in their guns.

 

[lrrifleman]

Georgian, I realize that some U.S. ammo manufacturers are introducing steel case ammo, and that is most likely SAAMI spec, but I have read that ammo coming from Europe and the former Iron Bloc isn't.

From talk in the pits at various matches and numerous years at Camp Perry, much has been discussed about shooting steel cased ammo in our target rifles. What I have learned is that steel cased ammo requires it's own cleaning regiment much like corrosive ammo. Apparently the sealant on the bullets creates a severe "super glue" effect after repeated use of steel cased ammo, and contributes to the non-contracting steel cases not readily extracting from firearms. I would suspect that the chamber of your P320 has a significant build up of the case sealant that is causing your extraction problems.

 

[Wavygravy]

Why use steel case ammo and complain about the pistol? Use brass.

 

[walnutred]

I have several firearms that were designed with steel case ammo in mind and zero experience SIGs, so take this for what it's worth. To me it sounds like you are getting varnish or other case coating/lubricant build up in the chamber. If one of my firearms was getting balky with steel case ammo the first thing I would do is thoroughly clean the chamber and barrel with carb cleaner and a good brush. Among other things carb cleaner is designed to help soften and remove varnish.

 

[younggun456]

I once had an issue with some steel ammo in my P320. A friend of mine said he heard of the issue and advised me to dump the box of ammo on a piece of cardboard and put a few drops of gun oil in the rounds and roll them around. After I did that I didn't have anymore issues

 

[seldon14]

I don't shoot steel case in anything. I don't shoot aluminum in anything either for that matter.

You only run cheapest gas in your car or motorcycle? We aren't just talking about price here.

I do. I don't own any vehicles that won't reliably run on 87 octane.

 

[Ruger Nut]

I once had an issue with some steel ammo in my P320. A friend of mine said he heard of the issue and advised me to dump the box of ammo on a piece of cardboard and put a few drops of gun oil in the rounds and roll them around. After I did that I didn't have anymore issues

Hmmmmm, interesting!

 

[Boxer9]

A lot of cars will run on lower octane gas, the knock sensor will cover your butt for a long time among other things. Guns don'thave those unfortunately. My point was, obviously, that when you run the cheapest junk you can get, it often affects performance. It doesn't have to be a Cadillac or high end sports car to need decent gas. Doesn't mean you have to put premium in it. I bet you wouldn't put old or gas with water in it just to save a few bucks, but often people do when they look for the absolute cheapest gas around.

A lot of people use cheaper ammo in their pistols, you can get factory new brass ammo pretty cheap. Even that has issues sometimes, far more rarely in the scope of how many use it, but sometimes. Steel ammo is probably the cheapest stuff you can buy, pretty dirty too. Some guns run it and some not so well.

Brass is literally a few cents more per round, but its your gun, so run whatever you want, if itll run it.

 

[Boxer9]

By the way, the Sig 320 X Carry has a Match barrel.

 

[sandog]

Georgian, you say you don't trust the Sig, but you aren't going to be using steel case as carry/self defense ammo are you ?
You just run it for practice/range ammo ?

I used to avoid steel in my rifles but have eased up on my dislike of it.
I run the better brands of steel along with some brass as well.
Never had the desire to run it in handguns though.
Rifles have a lot more extraction power than handguns, so are less likely to have problems extracting steel.

I think Old Goat hit upon the problem when he talked about tighter chambers being the cause of extraction problems.
Steel doesn't contract as much as brass during that millisecond after firing. Brass does better as it expands to seal the chamber, then shrinks after the bullet and powder gases have left the barrel, making extraction easier. Using steel case ammo can also be harder on your extractor because of it's poor contraction properties.

It sounds like you have a tight chamber, polishing it with a Flex-Hone brush and Flex-Hone oil will help. A cheaper alternative than Flex-Hone would be to put some polishing compound like Flitz on a bore mop and chuck the mop in a drill.

I doubt that steel case residue is the problem but it wouldn't hurt to clean the chamber well also. There were problems in the past of lacquer used on steel case ammo depositing in the chamber, but that was more of an issue of guys doing mag dumps in rifles using higher intensity cartridges.
.45 Auto is a low pressure cartridge, and they just don't get that hot when fired compared to 5.56mm, or even 7.62 x 39mm.

Steel case ammo needs some type of coating to prevent the steel from corroding easily.
Most all Russian manufactures gave up on the lacquer and switched to a polymer coating some years back which eliminated coatings getting deposited in chambers.

Is this extraction issue in your P320 just with one brand of steel case ammo ?
If so you could try other brands.

 

[sandog]

By the way, the Sig 320 X Carry has a Match barrel.

That could compound the extraction issues. Why would a manufacturer put a match barrel with a tighter chamber on a carry/defensive pistol ?

 

[OldGoat]

Yes, sandog has excellent comments on this issue! Dare I say that lots of trapshooters have noted that steel based hulls expand on firing and do NOT retract in some rather tight chambers on some shotguns (Ljutic for one example). Cleaning, polishing, and light honing of tighter than normal chambers seems to help.

 

[Bozz10mm]

If it worked with steel ammo at first and now it doesn't, I suspect the chamber is cruded up with residue that the steel cased ammo leaves. Does it work now with brass cased ammo?