ar-15 operation problems

[simmoag]

my ar-15 extractor has been ripping the case rims off some rounds causing the case to be stuck in the chamber. it does it every 100 to 200 rounds of the radway industries (british ss109) and every 5 rounds of the wolfe ammo. what should i do? i clean the gun every 300 or 400 rounds. could it be a burr in the chamber?

 

[hpg]

Cases may be too long and getting stuck. The extracter is not the problem. my .02 worth........hpg

 

[Ausserordeutlich]

Key info in this thread: "wolfe" (sic) ammo. 86 the wolfe (sic). Do an extra-thorough job of cleaning your chamber and around your extractor.

 

[jamesl]

if your ar is ripping case heads that means your extractor is good, you might take it to your local smith and let him check the chamber.

 

[James K]

Sounds like too much gas coming back, or too quickly. Has anyone been messing with the gas port or tube? A sticky chamber could also be the problem. Is that Wolfe ammo laquered steel? If so, the laquer could be coming off and gumming up the chamber.

Jim

 

[simmoag]

thanks

thanks for info. i think i need to try cleaning the chamber.

 

[guncrank]

That Brit ammo is a little hot. I had one recent customer who had a fired round stick in the chamber. After I got it out I checked and cleaned the chamber. The fired case should signs of excessive pressure in his Model 1 upper.

 

[DnPRK]

Jim Keenan hit the nail with his diagnosis. The case is stuck while the extractor pulls. The weakest link always fails first, which is the tiny case rim. Now we need to determine why the case is sticking.

Wolfe is notorious for leaving sticky residue in a chamber. When cool, it doesn't stick too bad, but when hot, it becomes a supernatural glue. An acetone-dipped bronze brush would be my recommendation for getting the Wolf goo out of a chamber.

Another possibility is an overgassed AR. This was the failure mode that killed a lot of GIs in Viet Nam.

Overgassing is caused by too big a gas port drilled in the barrel. It allows a huge quantity of gas through the gas tube to the bolt carrier. The bolt/carrier are trying to extract the cartridge case before chamber pressure has been reduced. The high chamber pressure keeps the cartridge case locked tightly to the chamber wall and the tiny case rim is ripped off.

The least expensive solution is to install a regulated gas tube or regulated gas block to reduce the gas flow.
http://www.brownells.com/aspx/NS/store/ProductDetail.aspx?p=9947&title=AR-15/M16+REGULATED+GAS+TUBE
http://www.pkfirearms.com/store/get_items.aspx?type=0&term=63

 

[FRANK1669]

Did this just start? was it funtioning properly before? if so on what ammo ? What upper are you using ? reason I am asking is my match grade 223 upper will not function on 5.56mm ( both ammo you mentioned is 5.56 Nato) you can usually shoot 223 through a 5.56 chamber but 5.56 through a 223 chamber is asking for problems. (a lot of people will say they are the same there not) There are a lot of AR-15 "type" rifle companys out there. a good srubbing on the chamber is a great Idea but before you start trowing parts at it find out what chamber your barrel is.

 

[fhp490]

you can use carb cleaner to remove the polimer and lacquer from the chamber that useually builds up. CDNN sells broken shell extractors for 223

 

[Coltlover]

Wolf ammo! You need to clean you rifle every 150 to SKS. As for my aM16 nothing but the good stuff. My SKS has lately only seen real brass as well, and no problem, Wolf tends to be half dirt half gun powder.