AR Sponsor
Posted: 8/26/2008 3:24:23 PM EDT
|
Gentlemen, I have been having a problem with a DSA brand semi-auto M4. I had four failures to extract today. I used a cleaning rod to tap out the stuck casings. The four stuck casings upon examination all showed a section of their rim was torn off, so I know that the extractor made contact with the casing. Previously I have had the bolt not lock open after the last round has been fired. I field stripped it at the range and cleaned under the extractor. I came home today and thoroughly cleaned the carbine. I am going back out to the range tomorrow with a new extractor in my range bag. Thank you for any help you can give me. Medicguy |
|
Wolf. There's your problem. 99% sure. If it's the laquered case stuff, the laquer is getting hot and lining the chamber, then cools between shots and causes a round to stick in the chamber. (Edited to add: I've heard the same sort of stories about the polymer coated wolf, though.) BUT - if by some chance the problem turns out to not be the ammo... I wonder if there's some sort of gouge or imperfection in the chamber? Are there any marks on the side of the brass that would indicate that? If the extractor ripped off the rim of the cases, I'd imagine the extractor/spring is probably okay. Back to the subject of Wolf ammo though... Make sure to clean your chamber immediately after shooting wolf ammo. Don't let it sit, or this problem will be more likely to happen. |
Laqured ammo melting off is pure urban legand. The problem with Wolf is the steel case dosen't expand and seal as well as a bress case. The result is more fouling in the chamber, and more FTE's as a result of the buildup. It also could be that your rifle just dosen't like Wolf.
|
Steel cased ammo has a known problem with chamber fouling. I have personally seen these types of problems with Wolf, Barnual, and Federal .223 Remington. Brass cased ammo simply seals better.
|
Have it your way, but it's funny how when I've shot the stuff in any of my rifles, the patches I use when I clean come out looking a funny color similar to the laquer. Granted, this was years ago, so they may have changed things by now. Either way, the result is the same though. Stuck cases. It's just better for people to shoot better quality ammo. |
|
Carbine's are known for rough extraction. If there aren't any defects in you chamber like machine marks or pits you can try: 1) Heavier buffer to slow down extraction. 2) M16 bolt carrier to slow down extraction. 3) Polishing out the chamber to ease extraction. 4) Adjustable or 'fat boy' gas tube to reduce the extraction force. My rifles have digested about 2k of Wolf with no* problems, but they have mid-length and rifle length gas systems. BSW *Wolf is stinky, inaccurate, and filthy. |
Wolf is also russian |
Lacquer does not have a color, it is a clear coating. Deposits, like from the crappy powder that Wolf uses that has that funny smell like ammonia when you shoot it, can leave deposits in a lacquer goo though. I have shot wolf and other steel case as well as brass case and I prescribe to the carbon fouling is higher with steel than brass theory, though I will not say I know why exactly, because as mentioned above at 50K pressure the mild steel should stretch and seal the chamber. Though we think of brass as soft (it is easier to machine and form) its tensile strength and yield strength are comparable. Not sure how this translates to reloaders who swear you can not resize a steel case because it is stronger so don't even try as you could damage your dies, but you can resize a brass case no problem. The theory as I understand it, is the thicker case of the steel ammo. I read on one internet thread someone had cut the cases of wolf and compared versus XM193 and showed the steel case to be much thicker. Thickness translates to strength and rigidity so maybe that's the ticket of not springing out and sealing the chamber. There is also the theory that the mild steel has less spring so to speak than the brass and actually has a little bit of deformation while the brass fully springs back to original dimensions. There have been a few threads on that theory but this is not close to being proven true. Military steel cased rounds are well known through the years as having extraction issues through the years. There are several remedies, such coating the case to stop corrosion and case swelling, having looser chamber tolerances, or like in my SVT-40 and several other Military rifles they actually machine in flutes in the chamber, so designed to try to balance the pressure behind the case (by allowing gases to get there) and thus aid in extraction. They did this without concern of additional carbon fouling of the chamber by doing so but were they right? The SVT-38/40 are known to bend recoil rods due to difficult in extractions when they occur and the bent rod is one of the well known problems with this weapon that made it unreliable and why they went back to a bolt action rifle (there were dozens of other reasons as well). I have one myself and did not fully understand this until one day it came flying out while shooting so I read up on it and discovered it was not unusual. One of the supposed remedies is keeping the weapon clean (including chamber) and lubricated (chamber dry). Wolf had lacquer cased rounds years ago, but due to the internet chatter at gun forums, at ranges, and by wholesalers/retailers/hobbyist attributing the lacquer to jamming, many of the Russian Manufactures in order to stay in the US market had to switch to the polymer coating which is harder and supposedly melts at much higher temperature (there was a thread here of a member burning older lacquer rounds and newer polymer rounds and other than the black spot the polymer did not come a part). There was also the problem with the primer sealant from some of the Russian Plants that did melt and goo up the back of the bolt when shot at a high rate and I experienced that myself finding goo mixed in with carbon fouling a couple of times that jammed up my extractor. This seems to no longer be the case with current sealant (sometimes the manufacturing plant does not even seal it at all) and there are some threads here about all of that kind of stuff. The box o truth site had a nice article how you could shoot brass rounds after shooting steel cased ones and the brass would get stuck and when extracted would be heavily fouled with carbon. They worked with some long time members here. www.theboxotruth.com/docs/edu18.htm I have been able to duplicate part of their results, where if you shoot brass you don't see the heavy carbon buildup, but if you shoot a bunch of steel cased rounds then brass that the first few brass rounds have that black carbon build up on them just like in the picture on the Box-O-Truth post. I did not duplicate the part that the brass rounds would jam after firing steel cased rounds, but I did not have the South African ammo they had. Though there are a lot of theories, with some as simple as if you buy cheap ammo it is going to shoot like cheap ammo and occasionally jam, ......from the posts here you can definitely say that the steel cased ammo, ......which is usually wolf,.... is less reliable. Whenever someone has Failure to Feed, Failure to Extract, Failure to Eject, the first question is always....."are you shooting wolf ammo" and more times than not the answer is yes. A lot of folks attribute the ability of many AR owners to shoot this stuff successfully and many having problems with wolf ammo to the tightness/tolerance of the chamber. This might make sense in regards to the stuff works fine in an AK which has much looser tolerances, but the AR has much higher tolerances, except possibly in regards to the various barrel manufactures in maintaining dimensional standards. Your problem of ripped off rims is one of the more common complaints from people shooting wolf and getting problems. Out of curiosity, when you use your cleaning rod to eject the steel case, does it seem "stuck" or "harder" to remove than say a brass round. If so I would attribute your problems to a sticky or dirty chamber. The other possibility is the well known problem with carbines as mentioned by Brian above where the timing of everything is so close to being off on a carbine, that the varying manufacturer tolerances in manufacture, fouling, burn rates of powder, etc is just enough to cause timing issues where the bolt tries to extract the cartridge prematurely before chamber pressures are reduced enough so there is not to much friction to keep it "stuck" so to speak. Ripped off rims is the symptom. As he mentioned you can slow down the bolt with a heavier carrier, heavier buffer, etc or addressing the friction by cleaning and polishing the chamber. There was a sticky here that really described the AR-15 mechanism in detail for a lay person so you could understand timing and how the gas port, length of gas tube, carrier type, buffer weight, etc all influenced the timing sequence. I would start with the simple stuff like cleaning the chamber with a chamber brush and HOPS then drying the chamber real good and then shooting quality ammo to see if the problem repeats. It is said by many at this forum that getting a mid length instead of a carbine length gas system has a noticeable improvement in reliability due to the frequent issues of timing with carbines. As for shooting wolf ammo, please understand that at this forum there is the "WOLF AMMO RELIGION" at this forum and it is like Iraq with the Shite (anti-wolf) and Sunni (pro-wolf) WOLF RELIGIOUS FACTIONS and that they wage rhetorical war with each other to gain religious converts to their side. I myself am the Agnostic, and will come around to believing in WOLF AMMO RELIGION when their god parts the Red Sea and proves precisely why wolf does/does not work. I simply see it as really cheap ammo that causes problems for some, but boy when you want to throw out a lot of rounds down range it sure is more affordable. Well good luck. |
AR Sponsor