Anyone Ever Break a Sako Extractor?

[tunacan]

Frustrating day at the range...

I just put together a little lightweight model 7 in a 6.5X47.

It has a one piece PT&G Bolt with a Sako extractor.

I was anxious to get to the range today to see what she could do.

This was my first time shooting it so these were fire forming loads. I also just turned the necks because my reamer is .290

Anyhow, I shot 15 rounds or so and then on the 3 shot of a particular charge my bolt handle wouldn't go completely up. I gave it a little pop upwards and the bolt came out with no brass. I then looked at the extractor and the claw was completely sheared off.

Has anyone experienced this? I thought the brass would give before the extractor....

The next 15 rounds were shot and extracted with a cleaning rod.

The gun does show a little promise for only being just 6.5 pounds

The group on the right was my last loads...I don't think I will try to push it any further. It looks like the accuracy node is a few charges back

 

[Lapua40X]

http://benchrest.com/archive/index.php/t-71497.html

http://www.sakocollectors.com/forum/archive/index.php/t-5108.html?s=fb2bc67259af4dff13ed7391c5492067

 

[Robert]

Tunacan,

Virtually all the self-gripping extractors breakages I have been aware of were during fire-forming of cases, when the extractor has to maintain the case instead as the shoulder..A duty it is not designed for.

R.G.C

 

[tunacan]

Thanks for the info. Thats what I was thinking too. The breakage had to occur during the forming of the case. I just couldn't see anyway possible for it to shear upon extraction.

I guess I will run some mild loads while FF cases. Hopefully that will stop this from happening again.

 

[lpreddick]

shot a 22 brx WAY too hot and after a struggle, got the bolt open and case extracted. bolt is a stiller and the extractor was broken off just in front of the retaining pin. a piece is embedded in the extraction groove of a very flattened case. the flash hole is double in size. since i remove the ejectors, brass flowed about 2 mm into the bolt face opening of the ejector. i bought a replacement and replaced myself and it shoots. my error! a superbly made action saved my face.

 

[tunacan]

The thing is, is that I didn't expand the case head and the primer pocket still looked good.
I was showing some pressure, but the primer wasn't "too" flat

 

[Robert]

shot a 22 brx WAY too hot and after a struggle, got the bolt open and case extracted. bolt is a stiller and the extractor was broken off just in front of the retaining pin. a piece is embedded in the extraction groove of a very flattened case. the flash hole is double in size. since i remove the ejectors, brass flowed about 2 mm into the bolt face opening of the ejector. i bought a replacement and replaced myself and it shoots. my error! a superbly made action saved my face.

Ipregick

What you describe is not a simply broken extractor, it is a BLOWN extractor by extreme overpressure,and this often has other consequence wuth gases flowing in the mechanism

R.G.C

 

[Robert]

Thanks for the info. Thats what I was thinking too. The breakage had to occur during the forming of the case. I just couldn't see anyway possible for it to shear upon extraction.

I guess I will run some mild loads while FF cases. Hopefully that will stop this from happening again.

Tunacan,

The milder load will not solve the problem if there is too much headspace clearance between you cases shoulder and the chamber?.

R.G.C

 

[tunacan]

There were a couple of cases that I sized just a tad too much when I was first setting up my FL die. I knew this going into it, but I thought that they would just form out with no issues.

Im pretty sure that this was the issue.