Posts: 244
Threads: 20
Joined: Feb 2012
OK I finaly got my rifle built. Took it out to shoot, it ran good for a new tight gun. I had to buff off the sharp edges on the extractor. The next problem I have is the fired cases are landing about 1-1:30. This tells me the bolt is coming forward befoe the case is out of the gun. I have a 5.2 oz buffer in the A2 tube. Thinking that a Tubbs flat wire spring might help but is there a heavier buffer that could be used, or should I get a hydrolic buffer?
[SIGPIC][/SIGPIC]
Posts: 2,075
Threads: 35
Joined: Mar 2011
Sound like it's over gassed. I'd try an adjustable gas block first.
+1: Over-gassed. Is this the gun that was/is having problems with Wolf 120gr MPT's, as well as Hornady? Your action is cycling way fast, which could explain the failure to extract issues too.
It might have a gas port that is larger than usual, or if you have a mid-length gas system, it is getting too much dwell time, especially with the 120gr class bullets and a 20" barrel.
I wish we could see some pics of the rifle, and more details about it, in order to help diagnose these issues, and get her running like a champ.
Posts: 244
Threads: 20
Joined: Feb 2012
This rifle is a J&T 24" bull barrel it has a rifle length gas system. Overgassing would also contribute to this but other than where the brass lands this thing runs like a champ. Put 100 rounds through it today without a single FTF or FTE, shot sub MOA groups with Hornadys. Pc is down and I can't figure out how to post pics from my phone. I will keep you posted.
[SIGPIC][/SIGPIC]
Posts: 244
Threads: 20
Joined: Feb 2012
Sent LRRPF52 a pm
[SIGPIC][/SIGPIC]
Does your extractor have an o-ring placed around the spring, if it does remove the o-ring and reassemble the bolt. I had to do this on top of filing the fangs off of my extractor, and now my rifle (J&T 24" Bull brl) functions perfectly. Brass in landing at 3 o'clock at about 3-4 ft. away.
Posts: 244
Threads: 20
Joined: Feb 2012
Bwild97 Wrote:Does your extractor have an o-ring placed around the spring, if it does remove the o-ring and reassemble the bolt. I had to do this on top of filing the fangs off of my extractor, and now my rifle (J&T 24" Bull brl) functions perfectly. Brass in landing at 3 o'clock at about 3-4 ft. away.
I did remove the o-ring after I found it was gouging the brass.
Was your brass landing in front of you?
[SIGPIC][/SIGPIC]
Ya, when it would actually eject. some times it would hit me in the face (lefty). It was really beating the shit outta my brass too, holding on to it and slamming it into the front of the ejection port, severely deforming the mouth of the case. I had to file fangs down to nubs, I can post pics if you like?
Posts: 244
Threads: 20
Joined: Feb 2012
Please post pics. But after thinking about it an adjustable gas block is reasonable. A larger caliber with a larger volume of gas, the same gas system may very well deliver too much gas to the bolt. Also talking to a buddy of mine he found up to 50fps increased velocity in a 308 by adjusting his gas system.
[SIGPIC][/SIGPIC]
Posts: 2,075
Threads: 35
Joined: Mar 2011
That's pretty much what I did to mine.
Posts: 244
Threads: 20
Joined: Feb 2012
Must be rough shooting all day on a Monday. I'll try it after modifying the extrcactor.
Btw how is your's grouping?
[SIGPIC][/SIGPIC]
I had problems with ejection of fired cases, and traced it back to an over powerful extractor spring. The extractor would push the case onto the opposite side of the bolt with such force that the ejector spring couldn't push it out of the recess in the bolt fast enough. I got funny ejection, stovepipes, and all sorts of odd things happening. As soon as I put in a weaker extractor spring, everything started working just like normal... Fired cases started dropping at the 4-5 o'clock position, about 6 feet from the ejection port after I put in a weaker extractor spring.
