Answer

What exactly has to happen to extract the spent casing? Before the root of the handle hits the 45 degree cam, do you need a hammer to raise the handle? Once it makes contact with the cam, hammer? What about after it runs through the cam, do you still need hammer to pull the brass out?

Is the round handload or factory? Any possibility of over pressure? Are there any unusual marks and scratches on the extracted brass? TL

Question follow-up

Sorry I had to break off before finishing. The ammo: Thunder Ammo brand, 416 Barrett, 415 gr. match solid, new Barrett brass. No scratches, scuffs, dents, or bulges. I does take a little pressure to close the bolt (smooth & constant pressure on the handle). I’ve never heard of Thunder Ammo, but this is what my customer brought in with the rifle. By the way, this is a girl’s gun. Yup, the gun has to weigh at least 40 pounds, and her boyfriend carries it from the car to the shooting bench. Loud as hell, but not much recoil.

Answer

Haven’t really worked on that particular rifle. So my comments here are based on understanding to the Mauser action, http://www.hoosiergunworks.com/images/f … 917_01.jpg.

Raising the bolt handle till it makes contact with the primary extraction cam. One should be able to do it with ease. The felt resistance should mostly come from re-cocking the striker. Observe the position of the bolt when bolt handle is being raised. There should be no in-and-out movement. If it does, bad news. The lock lugs may have been set back.

The root of the handle must make contact of the cam, or there will be no primary extraction. You said the handle doesn’t make contact with the cam. It is concerning as it can be an indication of setting back on the lock lugs.

45 degree on the cam may be too steep to generate enough mechanical advantage. It should be much shallower.

Question follow-up

Yes, this bolt actually comes apart a lot like the Mauser, just everything larger, and the front end being different. It has three huge locking lugs, and headspace was one of my first suspects right after a dirty/slightly rough chamber. However, there appears to be no headspace. I can’t even get one layer of Scotch invisible tape on the head and close the bolt without enough force to ruin the tape. This, of course was on a deactivated new round. And, if the locking lugs were set back, there would be headspace. I am beginning to suspect a short chamber. The only brass that shows the slightest amount of suspicion is the unfired dummy round. The front edge of the case has some shiny places on it. And there is resistance when closing the bolt. Maybe under pressure some of the neck is being pushed forward.

If that is the problem, I am not real crazy about buying a gauge & reamer for such a rare caliber.

My customer recently bought the gun at a gunshow, so they know practically nothing about the gun. They fired two rounds, and had to get a hammer out of their truck to extract those rounds.

Answer

Polish the chamber a bit more…..I usually stop at 400 grit like you but it won’t hurt to go to a bit higher grit. Then make the primary extraction cam work as it should. Build up the bolt so it has to come into contact with the small extraction cam surface on the receiver. If you ever get a chance to look at a Remington 788 examine the small extraction cam it has. These are known for breaking off the bolt handles and having poor extraction from the very small poor extraction cam surface. Keep us appraised, Ken

Follow-up Question

Thanks Ken, I was considering putting some material onto the bolt handle base to make sure it would try to make use of what it had for an extraction cam, but that is a drastic step I was hoping to avoid. I am sending a photo to your regular email of where the bolt stops now, and where I will have to start hammering. It chambers & extracts a fresh round just fine (as long as I don’t shoot it). However when I put in one of the empty cases, it won’t budge it past the point in the photo without some hard whacks with the hammer. I haven’t gotten the chance of polishing with 600 grit yet (all out until I run across town after closing today).

Answer

Don’t use fired cases to check extraction. They are oversized to the chamber they were fired in, and even if you are using cases fired in this gun the rounds most of the time won’t go back in easily and will get tight. A new round or resized case should work fine. Ken

Reply:

Thanks for everyone (especially Ken) for helping with this project. Ken gave me the confidence to weld up and reshape the base of the bolt handle so that it would take full advantage of the poorly designed extraction cam. I also talked to a local guy that has built many bench rest rifles, and as luck would have it, he is familiar with .416 Barrett ammo. It seems that not only is this stuff more rare than hen’s teeth, but the people that make it, all load it differently. The stuff the customer brought in with the rifle was much hotter than Ronnie Barrett’s original loading. That, with the poor design of the extraction cam made it impossible to extract with only the leverage of the bolt handle. I finally got some real Barrett brand ammo, and now with the improvements in the base of the bolt handle can extract Barrett brand ammo without using a hammer to beat on the bolt handle. It is far from a smooth action, but at least it works.