Fixed! Update: Savage .17 HMR Model 93r17 Light Strike Misfire Fix?

[tony270]

From day one this rifle misfired and over the years it progressively became worse. The first thing I did was to changed ammunition, then warranty firing pin and magazine. Then after several years I recently decided to send it back to Savage under warranty. I sent them a written history with an explanation of the defects. They replaced the outside extractor and firing pin. When I got the firearm back it still had a light strike and failed to fire more often than not.

So after a couple of firing pins, magazines and an extractor I decided to diagnose the malfunction myself. I started by tuning the bolt face and firing pin, then disassembling and cleaning the bolt, neither corrected the problem. Then I added a shim between the bolt and bolt face, fail because that only moved the stricker away from the firing pin causing more of a light syrike on the cartridge.

Then after more function checks I isolated the defect at the bolt locking handle and the slot on the barrel. The worn handle and barrel slot has opened the head-space causing the malfunction. I tested this by using a folded match-book as a shim placing it between the bolt handle and the slot in the barrel, problem solved.

What is the best fix? I can think of several but wanted to hear from the experts, I'm a retired mechanic.

[divingin]

Have a welder put a small bead on the bolt handle and machine it back down to fit?

[tony270]

Thanks for the response. That's one thought of mine too, should it be a gas brazing, eletric ark or mig?

[Twystd1]

Tig.

-T

[ar15barrels]

A very common cause of misfires is excessive headspace and that's what you found when you shimmed the bolt forward.
Those savage actions use the bolt handle root as their locking lug.

Don't try to tighten the headspace by pushing the bolt forward.
The proper fix for excessive headspace is to move the barrel further back into the action.

[tony270]

A very common cause of misfires is excessive headspace and that's what you found when you shimmed the bolt forward.
Those savage actions use the bolt handle root as their locking lug.

Don't try to tighten the headspace by pushing the bolt forward.
The proper fix for excessive headspace is to move the barrel further back into the action.

Thanks for the reply. What if I can clearly see that the bolt handle and the metal on the rifle are deformed causing the malfunction, at least by .025, the thickness of manila/file folder paper? I have a dial caliper that I can measure the head space with. Thanks

[ar15barrels]

Thanks for the reply. What if I can clearly see that the bolt handle and the metal on the rifle are deformed causing the malfunction, at least by .025, the thickness of manila/file folder paper? I have a dial caliper that I can measure the head space with. Thanks

Remove all the burrs and galling and re-machine the surfaces flat and lap the parts together.
Then set the barrel back to correct the headspace and grease the locking lug so it will not gall again.
If the receiver continues to setback, the receiver is too soft and the action is garbage.

[tony270]

Okay, thank you so much. I was thinking of smoothing out the action and applying a brass layer on the bolt handle through acet/oxy gas welding ( brazing) to make up for for the loss due to the soft junk action. Actually I don't think it's due to soft metal, but from the sharp edges on the action that worked against the face of the locking lug ( more of a mass producing issue). Then I would round the edges on the action and lap everything together after finishing the bolt handle, then do what you've suggested except moving the barrel, I don't think that's possible.

I'm not understanding, if the problem is at the bolt handle and action does that require the barrel to be setback to correct the issue at the bolt handle and action?

[tony270]

This little .17 has no locking lugs on the bolt, here's an image with an aftermaket handle.

[ar15barrels]

Okay, thank you so much. I was thinking of smoothing out the action and applying a brass layer on the bolt handle through acet/oxy gas welding ( brazing) to make up for for the loss due to the soft junk action. Actually I don't think it's due to soft metal, but from the sharp edges on the action that worked against the face of the locking lug ( more of a mass producing issue). Then I would round the edges on the action and lap everything together after finishing the bolt handle, then do what you've suggested except moving the barrel, I don't think that's possible.

I'm not understanding, if the problem is at the bolt handle and action does that require the barrel to be setback to correct the issue at the bolt handle and action?

Building up with brazing rod will leave you an even softer material in the locking lug.
The locking lug IS the bolt handle root that slides in the slot on the receiver.
That's why there are no other lugs on the bolt.

The area you are working on IS the area that is containing the firing pressure.
I would NOT build it up with brazing rod as the brazing rod is softer than the receiver to start with.
If you MUST build it up, build it up with hardfacing rod and then machine it all back to flat/square.
That will give you a harder surface to handle the firing pressures.

You obviously need to deburr the edges after remachining the locking surfaces after welding so it will not happen again.

The easiest way to move the barrel back is to remove it from the action, thread the front of the action, chop off the old barrel tennon and then thread the barrel and rechamber.
This will not only fix the headspace, but it will also give you a MUCH more solid junction between the receiver and barrel.

I have converted a couple of these savage rimfires to thread-in breech setups.

[tony270]

Thanks for the schooling ar15barrel. I'm going to have a weld bead laid on the bolt handle, then I'll clean it up and finish by burnish the action and bolt handle surfaces. I'll post the finished product, thanks again.

[ar15barrels]

I'm going to have a weld bead laid on the bolt handle, then I'll clean it up and finish by burnish the action and bolt handle surfaces.

Lay on hardfacing filler.
It's harder than standard filler wire.

[tony270]

Okay I'm back with an update. The fix was tapping the locking handle for a set screw, then trimming the set screw, and then red loctiting the screw and installing it to the correct depth.

[G-forceJunkie]

So now you have an even smaller contact patch rubbing on the soft reciever? How hard do you think that screw is? Is there a reason you insist on NOT doing everything a professional gun smith with experience with this exact problem recommended? Your fix will work for now, but it will wear out faster thanit did originally.

[tony270]

I'll still be able to make adjustments, and by the way the idea, drilling and tapping was preformed by a professional, at a Gun Shop, $40.00, lol. I identified the defect and cut and set the set screw. I'm not a novice when it comes to mechanics.