Printable View
I have a PT&G bolthead 6.8 SPC sized. I run the bolt head without an ejector and use a single feed sled.
I have an issue whre the extractor is not moving or 'snapping onto' the case head, I can either angle the rount into the bolt by hand (poor man's controlled feed), or slam the bolt into the case, which cuts the brass.
The rifle was headspaced witnout the ejector or extractor installed and it shoots fine. I am just looking on how to troubleshoot the extractor.
Thoughts?
In a bag or a box to control parts from ejecting across the room, push the extractor off the bolt head. Underneath you will find a detent ball and a spring. Clean, lubricate and reassemble. Some get a larger ball like a .140" to fix issues but I don't think it applies here.
I agree with Robinhood. After just having problems with a PTG bolt head also found the spring hole for the extractor was .150 diameter and the savage factory spring was .149. .001 clearance leaves little room for debris. Also the hole edge had not been deburred, also interfering with free movement of the spring and ball. A quick internal sanding with 320 paper may help with better movement of the extractor.
A second thing you might want to check is (at least with my PTG bolt head) the depth of the case head bore to the protrusion of a sized case from the chamber. My "barrel try" rifle with the PTG head has seen numerous barrels. On one factory .243 barrel I tried a couple of months ago actually did not headspace until I removed about .005 off the breach face. The PTG I believe was .119 and the head space gauge protrusion was .115. The bolt head actually touched the barrel before the go-gauge was snug! This factory barrel to me was out of spec (I usually try for .120-.125 protrusion when chambering). The factory bolt heads are about .113-.115 deep. I also removed about 3 or 4 thou off the bolt head rim at that time. Shoot for about 7-13 thou between the bolt head and breech face. Keep in mind the sized case will be smaller than the go-gauge.
The jist of all this is that if a false "feel" happened at head spacing the bolt may be pushing the case in a tad too far for the extractor to grab it.
Just a thought,
Randy
Thanks. I have have the extractor off a couple of times. I have learned to use a clear bag.
Is there a way to function check the extractor outside of the action? From what I see on the brass, when I force the bolt over the case head, it is cutting into the brass but not all the way through. So eventually the extractor gets around the case head and is able to do the extraction fine at that point.
I.guess I am seeking to visualize the behavior of the extractor on the push fed chambering of a round.
I will clean that area out and add lubricant. Free movement is definitely not how I would describe how the extractor acts even outside the action.
I will measure the bolt face the best I can. This is a frankengun as it is a short action bolthead on a long action bolt using parts I bought (I think) from SSS 3 or 4 years ago and had been sitting.
It seemed to headspace well and it ignites the primers every time. Re-cocking is pretty stout but not horrible.
Is it possible that the rim is landing on the "flat" part of the extractor and not on the taper? If it is you can try to re-shape it with a small file (ie; shorten, re-slope and add more undercut). It's only a $5 part so might be worth a try.
Is it possible that you are using a .223 extractor, and the tail is stopping the extractor to move enough to snap over the rim. If so replace extractor with a .308 size or shorten the tail.