Extractor Breaking

[lawrence97]

Do any of you have any suggestions or a cure to this problem?

I have a CG Millennium action which is very much like an RPA Quadlock and my extractor has broken 3 times while fire-forming for a 6 dasher. The action or extractor has never had any issues before when using a 6.5x284 or a couple of 6br barrels. The extractor problem started with the 6 dasher barrel. The first time it broke on the 5th fire forming round (no pressure, very mild load for fire forming and the case fell right out when barrel was tilted up). I acquired a replacement and it was installed without any problems and it broke the extractor on the 5th round.
I then decided to remove the barrel and there was a very light extract mark on the face of the barrel. I acquired a 3rd extractor and sent the barrel and action to my gunsmith. The barrel face was relieved .025" and the new extractor was cut slightly on the mill so that it would not go past the bolt face. Just my luck and this extractor went for 10 rds before I noticed it was broken..... I am using the jam method to fireform. I have done this before with my other dasher and never had a problem. I am using lapua 6br brass straight out of the box with 31gns of varget and an 80gn berger jammed into the lands.

Not sure what else to do at this point.... I am not able to find another rpa quadlock extractor here in he USA unless someone has one tucked away! or is there anyone capable of manufacturing or adapting something to make it work?

What could be causing these extractor failures?

Thanks.

 

[jonbearman]

What type of extractor is it, could you post a picture of it installed and the broken ones? Is this a titanium action or steel and why cant the manufacturer help you or are they out of business?

 

[dkhunt14]

Maybe the bullets are slipping and the firing pin is driving the case forward. I am just guessing but maybe that is what is breaking them. I don't like short light bullets to fireform with. I clean the mouths of the cases with alcohol or acetone. I use a lot of tension and a long bullet like Sierra 107 so I have a lot of bullet in the neck. I also use a pretty good jam. I also use a Federal primer because they are a lot softer. Matt

 

[lawrence97]

It is a sako style extractor. I tried looking at brownells offerings but they are slightly different. My bolt is steel and it has 4 lugs. The extractor is milled into one of those lugs making it different than a sako style extractor that you would find on a conventional remington 700 bolt. The extractors have all broken right at the 90deg bend that is inserted into the bolt body and has the plunger/spring pushing on it. The claw is perfectly fine with no stress.

As for finding a replacement extractor I may have to reach out to England (RPA) or New Zealand (CG) to probably pay double or triple to have such a small part imported/shipped! I hope to find someone stateside or a skilled machinist to make a few for me. Here is a link to what my rifle and action look like:

http://www.6mmbr.com/gunweek065.html

If you scroll to the bottom of link, you will find a pic of what my bolt/extractor looks like:

http://www.hps-tr.com/products/actions/

 

[lawrence97]

Matt, I'm using the softer federal primer also. I think that if the bullet were slipping I would have inconsistent ignition or misfires if the firing pin pushed the case forward. Also, the extractor claw closes onto the case rim upon bolt closure so I don't think the case can go anywhere.

This whole extractor issue has me puzzled. Not sure why they are breaking!

 

[jonbearman]

Do you have an ejector and maybe the spring is to stiff and it is opening the extractor to much and bottoming it out and stressing it at that point . Then when you rechamber and fire it breaks in the battery position from being bottomed out with a fracture caused by ejecting the formed case.

 

[lawrence97]

The spring tension is very light and softer than what you would find on a remmy 700 with sako extractor. I think that if it had too much tension, I would have had problems when I was running a 6.5x284 and 6br barrels on the same action. The issue has only been with the dasher barrel. All barrels for this rifle were chambered by the same gunsmith.

Thanks for the info.....

 

[lawrence97]

Oops, misread and thought you were referring to the plunger/spring tension for the extractor!

As for the ejector, it does not have a spring. It is completely mechanical and similar in function to a Kelbly TG ejector.

 

[Rustystud]

not familiar with this action. But if it is like the RPA it has a spigot type tenon. They are supose to be made loose for a reason.
Nat Lambeth

 

[lawrence97]

Nat, my action is like the rpa quadlock. Not sure on the spigot part! All the barrels I have for this action are threaded the whole tenon length and the breach face is flat (no cone). This rifle is setup as a switch barrel and barrel work was done by Dwight Scott. I am not familiar with the barrel thread specs but I am sure Dwight knew what he was doing. I compared my dasher barrel to the other barrels and I do not see any difference. I will measure tenon length or measure from breech face to shoulder to see if there are any differences.
As mentioned earlier, I am only having the extractor issues when fire-forming for the dasher. Could this be a weak extractor design that cannot handle fire-forming from 6br to a dasher?

What else can I measure or check?

 

[jonbearman]

How much side movement could you get before the extractor bottomed out in the relief in the bolt body. I am thinking that when it snaps off the cartridge or grabs it ,it cant move enough without bottoming so to sopeak in the bolt body causing strain on the extractor right where it plugs into the body.

 

[lawrence97]

Can't really measure it now since it broke off but it had a generous amount of movement when I pressed with my finger. I don't think it was bottoming out because I played with it a few times using a fired case and it engaged and disengaged the case rim without any problems.

 

[Robert]

What could be causing these extractor failures?

Thanks.
[/quote]

Laurence:

THE CAUSE IS SIMPLY THE FIRE-FORMING directly......

Every extractor breaks on the models you mention were caused by trying to direct fire-form shoulder cases without creating a "false shoulder first...

The false shoulder is created by first opening the 6mm neck to

On the examples I know, usually, the user understand that after the 2d break!!!!

An extractor is not intended to hold the blow of a firing pin, the shoulder, false or real, is there for that.
7mm or .308 and creating a small shoulder on the dimennsion desired and rhen use it as a temporary shoulder to fireform...Not only your extractor, but also your cases will also prefer this milder treatment.

PM me and I will see what can be done.

R.G.C