Powder burn on one side of spent cases.

L

lasvegastransplant

New member
Is this a normal thing with Bersa T's? I have never noticed it with the few guns I own except the Bersa.

Got it used but like new condition. The coating was perfect. After the first 20 shots it showed signs of use on the coating where the hammer bites. So based on that I believe it was never or hardly fired.

Could there be some issue with the barrel? It is on every round. Are some guns just prone to doing this? Other than the trigger spring coming lose once it seems to fire fine and on target. Any feed back about the burnt cases would be great. Thanks for reading
 
Brass, besides holding the components has the task of working like a gasket.

When it fires the brass expands sealing the chamber. If you have powder burns on the outside of the case then the powder charge isn't hot enough to expand the case to seal the chamber.

You say the gun shoots good otherwise, then I'd say don't worry about it, Cases will clean.

If you are shooting reloads you can step up your powder charge a tad. If its factory loads then maybe the chamber has been cut a bit large, it happens.

When people do a run of barrels they use a chamber reamer to cut the chamber, like anything else the reamer wears out. Factory's keep tabs on this and if it gets too warn they replace it. So with a new reamer, the chamber will be tight, as it progress the later chambers will be looser, but you can bet they replace the chamber reamer before it gets too bad.

Unless your chamber is so bad its splitting cases, I wouldn't worry about it. Just was your brass before you reload it.
 
Hello, lasvegastransplant. I too have noticed this burn on one side of case..and with some not so light loads in rifle cases too. Here is my WAG...Could it be that the case..which isn't a press-fit in the chamber anyway, could be lying on bottom of chamber..with extra clearance around the 6:00 position? When fired, the top side must expand further to seal..giving gases more time to rush past neck?
 
Winchester White Box and Some Remington JHP is what I shoot.

Now I'm going to save my factory ammo and try my reloads. The cases look fine just dirty like I said. Maybe with some fine tuning on my reloads I can get a proper seal/expansion. I've yet to fire my first reloads. I was trying to understand and hoping the barrel wasn't out of wack. Thanks :)
 
The link I posted was referring to WWB. I think the powder burn is just a byproduct of that particular manufacture. So, like I said earlier, I think you have nothing to worry about. They just shoot a bit dirty.
 
Yes I just got done reading it Shaun P.

I'm sure it's fine also.

I hope it is noting. I am using WWB but the Rem. does it also...? I hope with my reloads the issue can be resolved. Thanks for the link.

I think I will mark a few cases with marker and load them in the same position to see if the powder burn is consistently in the same place. Could this be a way to check if the barrel has a "leak(not sure if it is the right word) or a defect?" Just wondering. Thanks everyone
 
That I'm not sure of. I'll be honest, I don't really even have access to WWB where I live so it's not something I have much experience with. Remington we have much of, but I haven't noticed any peculiar powder burning or cracked casings or any of the like on anything but surplus ammo. WWB is pretty prevalent, you're not the first (and surely not the last) to have this anomaly. Let us know how the Remington fares. The fact that it's powdering casings is pretty bizarre to me (as a previous poster mentioned, it should act as a gasket) but, who knows. Most of the electronics I own have had some bizarre behavior and then all of a sudden worked fine. I'm sure it can be the same with ammo/guns. I will definitely keep an eye on this myself as I've never really heard of it before. Sounds scary, but apparently isn't? At least you're in the clear and that's what's important! Thanks anyway for the post!
 
All of my semi autos do this to a certain extent. One M1911 using light loads does it real bad. What I found it to be is the extractor pushing slightly on one side of the brass case. So the gases escape at that small gap. On my M1911 the burn marks on the out side of the brass are at the 3:00 position, right where the extractor is. I found this by marking the case heads at the 12:00 position and loading them one at a time then firing. Burn mark is centered at 3:00 right even with the extractor.
 
kraigwy, you stated,

"When people do a run of barrels they use a chamber reamer to cut the chamber, like anything else the reamer wears out. Factory's keep tabs on this and if it gets too warn they replace it. So with a new reamer, the chamber will be tight, as it progress the later chambers will be looser, but you can bet they replace the chamber reamer before it gets too bad."

I'm curious about this from a logical perspective. Wouldn't a worn reamer actually cut a tighter chamber because the reamer's dimensions would have decreased after usage?

Or does a reamer begin to cut erratically and in a less uniform manner after usage?

I'm asking because I don't know.

Thanks -

gd
 
Mike38 you did exactly what I am going to try.

Sound possible that the extractor may play a roll in the powder burn. I pulled it apart and dropped a few rounds in the barrel. A little wobbly(lose fit). I'm almost positive that the pressure from the extractor could cause this like you stated.

AS FOR THE REAMER....
I'm no expert AT ALL but I also have trouble figuring how it could wear out and somehow make a bigger diameter hole... :confused:

Oh well. The Wife and I already lost confidence(for a CCW) in the Bersa after the trigger spring came loose. I had a different Thunder years ago and never had any issues. Not one. Thanks for the replies.
 
Books says light loads cause powder burn on cases.

I'm a newbie reloader, and the ABC's of Reloading suggests that if the powder load is too little, the case doesn't expand as much as it could and hence there is a gap between the case and the chamber and there can be a burn on the side of the case as a result. I shoot the recommended load for my 44 mag, and occasionally get that burn on the case.

Live well, be safe.
Prof Young.
 
two things, first the brass. Now the books say a too light powder charge will cause the burn on the outside of the case. And they are right.

However, brass vaires in elsaticity from lot to lot, and between makers. Sometimes cases don't seal completely, even with the "proper" powder charge. Also, since the brass seals, and then "springs back" away from the steel of the chamber, it is possible to get gas residue on the cases, at the mouth, with nothing wrong, at all.

Now, cases loose in the chamber, held off center axis by the extractor, could show a mark down one side. A loose chamber is both a problem, and not a problem, depending on the specifics. With a handgun, firing a low pressure (relatively) round, a little slop is often not a terrible thing. In fact, guns intended to operate under the worst possible conditions (military arms) are often cut with slightly oversize chambers, because reliablity is preferable to best accuracy.

As to the reamer question, a new reamer cuts the max size hole (chamber), as it wears, the hole gets slightly smaller. When it reaches min dimensions for spec, the reamer is replaced.

However, although the cut is smaller from a worn reamer, it is also possible for the worn cutting edges to "chatter", and not cut a perfect chamber. Obviously, good machinists take pains to avoid this, but sometimes bad ones do get out the door.

Even if the chamber is "off", its only a problem (in a pocket gun) if it interferes with proper functioning. As long as the gun feeds, fires, and hits close enough to the point of aim to satisfy you, then it doesn't need fixing.
 
When it fires the brass expands sealing the chamber. If you have powder burns on the outside of the case then the powder charge isn't hot enough to expand the case to seal the chamber.
Click to expand...
This is correct. However, when the burn is only on one side of the case instead of fairly evenly distributed around the outside of the case that suggests that the chamber is not symmetric.
 
I see it on almost all my .45 handloads, regardless of the gun in which they're used. Some have postulated that it's the area where a small amount of propellant gases leak past the case mouth before the case fully seals against the chamber wall.
 
I used to see it on my light practice handloads in .45 ACP. Not so on my "major" handloads, though, so I expect you guys are on the right track.;)
 
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