Gunsmithing Sako Extractor Issues?

[Tip em over]

Any suggestions on issues with a Sako extractor?
I have a 7 WSM built on a Rem 700 action that is giving me grief on extracting cases from the chamber.
New lot of Winchester brass. Started working on load development and chambered the first round making sure things looked ok.
The first loaded round didn't extract. After that ..I ran all the new unsized brass through the rifle and got maybe 25% of the cases to extract.
I pulled the extractor, cleaned everything and slightly stretched the coils of the spring and noticed a drastic improvement in extraction of the cases but still maybe 20% are not extracting. These same cases will fall out of the chamber if the rifle is tilted up. The extractor snaps on the cases fine when just checking them with the bolt removed.
I tried a new extractor kit from Brownells. This extractor doesn't even snap on a case rim or pull a single round out of the chamber.
I haven't fired the rifle yet...but am thinking after the cases are fired in the chamber that I could feasably have to push them out with a cleaning rod if they are extracting unfired.

 

[bohem]

Re: Sako Extractor Issues?

<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: Tip em over</div><div class="ubbcode-body"> I could feasably have to push them out with a cleaning rod if they are extracting unfired. </div></div>

This is asking for a crown damaging accident, amongst other possible negative outcomes.

I don't have much experience with Sako extractors, however, in seeing the mechanism work my first suggestion would be to replace the rear spring to something stiffer.

ETA: It may be a defect on the claw of the extractor, loosely controlled geometry due to manufacturing defect is a good way to have extractors fail. Can you see if the extractor itself is worn on the engagement surfaces.

Just some more thinking on what might be the issue, like I said above, Sako extractors are not an area of troubleshooting expertise for me.

 

[DAVETOOLEY]

Re: Sako Extractor Issues?

As I understand it this is with all virgin brass. In all likelyhood the ejector is pushing the case forward and will not allow the extractor to snap over the rim. Remove the firing pin and repeat the process. When you have a case that doesn't extract push the bolt forward and listen for the click when the extractor snaps over the rim. If by chance the barrel was fitted very close to the bolt nose then fire formed brass and/or seating the bullets to touch the lands will solve your problem. Sounds like someone did a good job as I fit them as closely as possible to get the most extraction possible from the bolt cam on opening. Rim thickness+ .005" is what I shoot for.

 

[gamma]

Re: Sako Extractor Issues?

Check to see if your counterbore dimension is interfering with anything. If its a little too tight it may be stopping the extractor from opening out and clipping over the rim.

 

[Tip em over]

Re: Sako Extractor Issues?

Thanks guy's!

 

[mattlewis]

Re: Sako Extractor Issues?

Any luck? I'm having the same problem, right down to the clambering and make of brass.

 

[LRI]

Re: Sako Extractor Issues?

If the ejector is pushing the case forward enough to not allow the xtractor to purchase the rim I would first ensure the gun is headspaced properly.

That or ensure your not going bezerk with your sizing die and bumping shoulders back a ridiculous amount.

The extractor should not extend beyond the nose of your bolt. If it does it was fitted wrong, but it still doesn't explain your problem.

Next, the rim's outer periphery should cause the extractor to lever out/away from center, once the claw slips past the rim into the groove of the case it should snap back and be in almost the same position as when the bolt face is empty. The spring/plunger should load slightly against the case rim. It should not stick out beyond the OD of the bolt nose/body. If it does you'll have issues when chambering.

You can check all of this by simply inserting a case into the bolt face while its in your hands and out of the gun. If it bites the rim in your hands it should work in the gun. If it don't there's other stuff going on. (Like H/S)

One thing you could do is whip up a dummy round. Seat the bullet into the lands so that the rim is firmly seated against the bolt face. If it suddenly starts working then guess what? Its likely HS or your banging shoulders too far.

Check the HS first as this will cause all of the symptoms your seeing.

Good luck and be careful.

C.

 

[DAVETOOLEY]

Re: Sako Extractor Issues?

Chad

I used to fit extractors to fit individual rim thickness. I would go for .005" clearence after it snapped over the rim to get the most from the bolt camming open. Well I soon learned that violated rule #1. It made the phone ring. Virgin brass and a strong ejector spring and the extractor would fail. The second time around on the brass everything would work fine. It's a tolerance stacking issue.

A quick check is to bump the closed bolt handle forward, compressing the ejector and see if the extractor clicks over rim.