Sig P320 Failure to Chamber Problem

J

johhny12gauge

CGN frequent flyer
Rating - 99.5%
216   1   0
Hello, I'm out of ideas as to why I'm having this problem and I'd appreciate anyones input that may help. I have a P320 that is having issues with failure to chamber. Every time recently that I rack a round in the gun it will fire that first round and eject the casing without issue. The gun will not pick up the next round and I have to tap and rack it in. For the rest of a stage it seems the gun runs fine when dry or when changing a magazine with one in the pipe remaining. The gun previously had no issues and this problem only occurred recently.

My ammo has not changed and is full power 124 grain reloads (4.3 grain Win 231), the gun is clean, this problem occurs with all 5 mags I own, magazine springs are very little usage, the recoil spring and guide rod were changed but the factory guide rod/spring give the same problem. I had the barrel reamed recently but using another P320 barrel the problem continues.

This is its configuration: full Legion lower with grip weight, VTAC Upper, stainless recoil guide rod and lighter recoil spring, 4.7" factory barrel

I'm not new to pistols or shooting so I doubt grip would be a factor but am open to input there or anywhere really. I'm getting to my wits end with the gun.

Thanks for reading
 
Are you checking each of your rounds in a gage or in you chamber ?
I will put money the problem is with your ammo most likely brass. Check OAL of offending round(s) if you can. Check crimp.

Heck your mag : Dropping half a full mag on hard surface is a killer on feed lips. Number your mag and try to identify which one is giving you the problem.

Your light spring can also be a culprit. When you start changing parts..you don’t know where it will end up reliability wise. Put back the factory springs in it.
 
I barrel check them and the barrel was reamed so even slightly bulged brass would be fine.
The ammo I run at about 10k/year in my other guns and run smooth, no issues OAL or anything else.
I do crimp a bit much, could that cause a failure to chamber?
I only shoot outdoors and it's more sand or grass.
I will check all the feed lips. The problem occurs with all 5 mags.
I tried putting the factory recoil spring/guide rod back in and the problem still occured.

Thanks for the feedback
 
Last edited:
johhny12gauge said:
Hello, I'm out of ideas as to why I'm having this problem and I'd appreciate anyones input that may help. I have a P320 that is having issues with failure to chamber. Every time recently that I rack a round in the gun it will fire that first round and eject the casing without issue. The gun will not pick up the next round and I have to tap and rack it in. For the rest of a stage it seems the gun runs fine when dry or when changing a magazine with one in the pipe remaining. The gun previously had no issues and this problem only occurred recently.

My ammo has not changed and is full power 124 grain reloads (4.3 grain Win 231), the gun is clean, this problem occurs with all 5 mags I own, magazine springs are very little usage, the recoil spring and guide rod were changed but the factory guide rod/spring give the same problem. I had the barrel reamed recently but using another P320 barrel the problem continues.

This is its configuration: full Legion lower with grip weight, VTAC Upper, stainless recoil guide rod and lighter recoil spring, 4.7" factory barrel

I'm not new to pistols or shooting so I doubt grip would be a factor but am open to input there or anywhere really. I'm getting to my wits end with the gun.

Thanks for reading
Click to expand...

If it was my gun, I would buy 50rounds of factory ammo and test.

If the issues continue, I would borrow buddies magazine that works and tested it again with factory ammo. If both failed, gun would be going to MDC Firearms for a repair.

Cheers,
 
Check out "honest outlaw" on youtube.

He is pretty well known and has had problems with all the 320's he's tried.

Stovepipes and round jammed in chamber IIRC.
 
Grip riding the slide. A burr somewhere slowing the slide, it will eject but not go back far enough to pick up the next round. Dry slide rails.
 
To add to my initial comment, i would have someone else shoot the gun to see if they are experiencing the same issue;

  • With your reloads,
  • With factory ammo, and then
  • With factory ammo and new magazine.

Keep us posted - i hope you get it figured out!

Cheers,
 
So after writing down all your great points I took it to the range today. Had 2 different shooters try the gun with my ammo and one of theirs. No problems. It’s my support thumb. The P320 is overly sensitive to my grip. Never had this issue on any brand or type of pistol. Best case scenario it wasn’t the gun and only the operator. I’ll learn to adapt.

I appreciate the help and will pay it forward!
 
johhny12gauge said:
So after writing down all your great points I took it to the range today. Had 2 different shooters try the gun with my ammo and one of theirs. No problems. It’s my support thumb. The P320 is overly sensitive to my grip. Never had this issue on any brand or type of pistol. Best case scenario it wasn’t the gun and only the operator. I’ll learn to adapt.

I appreciate the help and will pay it forward!
Click to expand...

I am glad to hear you figure it out..!!!!
It doesn't sound like it will be an expensive repair... ;)

:cheers:
 
Last edited:
I think I’m more unique with my problem. Most shooters don’t grip as hard with their support thumb as I must to induce failures. I think the design itself is good. I wouldn’t be concerned.
 
You must log in or register to reply here.
Back
Top Bottom