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mytwo60
05-17-2010, 10:24 PM
So today I noticed something on the bolt head of my Stevens. There is a small indentation completely around the pin hole. It's not flat and smooth like it should be. I don't have any pictures as my cheap camera cannot focus clearly on the pin hole. It looks like someone used an oversize punch and lightly tapped over the pin hole creating a slight dent. This is a brand new action.

Anyone seen or heard something like this? Bolt head defect?

Smokey262
05-17-2010, 11:46 PM
Are you speaking of the firing pin hole, or the extractor pin hole?

Salvo
05-17-2010, 11:56 PM
I've noticed the same thing on a new Savage that I recently got out of the custom shop. The bolt face is not flat and true, but looks slightly indented or "dished in" around the firing pin hole.

Out of the first box of shells I fired, I got one pierced primer, which is what you have to look out for with the bolt head in this condition. If you are not getting pierced primers then yours may not be bad enough to worry about.

It's hard to say how the bolt heads get past QC and make it out the door in this condition, but apparently they sometimes do. Yours is not the first story I have heard about this, and it has happened to me as well.

The best fix is to contact the service department at Savage and see what they suggest.

You can try a home repair, but only if you are set up to check and adjust the headspace. Truing up or changing out the bolt head is likely to change the headspace, which is easy to deal with if you are set up to swap barrels but otherwise is best left to a gunsmith.

If in doubt, talk to the Savage customer service folks and let them make it right.

BillPa
05-18-2010, 12:40 AM
I've noticed the same thing on a new Savage that I recently got out of the custom shop. The bolt face is not flat and true, but looks slightly indented or "dished in" around the firing pin hole.

Out of the first box of shells I fired, I got one pierced primer, which is what you have to look out for with the bolt head in this condition. If you are not getting pierced primers then yours may not be bad enough to worry about.

It's hard to say how the bolt heads get past QC and make it out the door in this condition, but apparently they sometimes do. Yours is not the first story I have heard about this, and it has happened to me as well.

The best fix is to contact the service department at Savage and see what they suggest.

You can try a home repair, but only if you are set up to check and adjust the headspace. Truing up or changing out the bolt head is likely to change the headspace, which is easy to deal with if you are set up to swap barrels but otherwise is best left to a gunsmith.

If in doubt, talk to the Savage customer service folks and let them make it right.




Cratered and pierced primers are a combination of two things provided its not from other issues, loading and etc.
One the boltface maybe dished to some extent and a slight chamfer around the pin hole. Its a result of the final polishing of the boltheads.

Two, the firing pin tip contour.

The fit as they come from the factory with the protrusion set to .020", the approximate amount the primer stops the firing pin forward travel.

http://i50.tinypic.com/2ur0aaw.jpg

One the left is the factory pin tip, on the right re-contoured.

http://i49.tinypic.com/mj5hz.jpg

The combination of the factory tip contour and the chamfer allows a gap between the pin tip and pin hole for the primer cup material to flow.

With the boltface squared and the tip re-contoured with .020" protrusion. Goodbye craters.

http://i48.tinypic.com/2e3oq5s.jpg


It's hard to say how the bolt heads get past QC and make it out the door in this condition
Check out Remington's pin to pin hole fit sometime! ;D

Bill

dcloco
05-18-2010, 12:43 AM
Just about all bolts have this condition.

Good gunsmiths offer the service of bushing the firing pin for this reason (and other reasons as well).

I trued up a couple of my boltheads. Should have bushed them while I was there...next time I will.

Shoot it and don't worry...unless you are getting some extremely strange looking primers from factory loaded ammo.

mytwo60
05-18-2010, 01:34 AM
Salvo,

Thanks for the response. I think you know exactly what I meant about the "dished in" around the firing pin hole. I have never seen anything like this before and I own many bolt action rifles. I will give Savage a call soon.

Smokey,

I was referring to the firing pin hole.

Bill,

I am not sure if you understood my question or the issue. The pictures of the bolthead is awesome, btw. Now just imagine a "dished in" area around the firing pin hole. I have no clue as to how the indentation gets there. I mean it looks like it took some serious force to put a indentation like that. Wish I could snap a photo of it.

dcloco,

I will shoot it for sure but one would imagine that any cratering in the bolthead when shot will be filled with something. In this case it will be the primer.

nomo4me
05-18-2010, 03:20 AM
Heh
My LRPV 6br bolt face was so dished I didn't dare fire it. I didn't want to ship the gun back to Savage either. I bought a new bolt head from Savage and that one was only dished about half as bad as the original - but still such that Savage's contractor for these parts should be ashamed of their QC. And Savage for that matter - it's their name going on the product.

Since I had the barrel off, know what I did? I stuck a cut-to-fit piece of 220 wet/dry paper to the base of a 6br case and chucked the new bolt head into a drill press and turned her on and held the case head against the bolt face as she spun and took about .005" off that face. It's still dished slightly around the pin hole but I can fire the gun without worrying about pierced primers. I still had to lap the lugs as the ceramic tumbling beads wear them unevenly, taking more off farther away from the bolt body.
In geology it's called spheroidal erosion. Principle works the same on metal objects in a ceramic tumbler as the beads are designed to attack any sharp edge and they don't know the difference between a machining burr and the 90 degree rim of a firing pin hole or the square face of a locking lug.


Bubba gunsmithing I know, but I've got brass rub signs on the entire bolt face and it shoots half moa with ammo loaded on a progressive press so I didn't screw it up too bad I guess.
Too bad Savage doesn't tell their contractor to square the bolt and lug faces AFTER they run them in the stoopid ceramic tumbler.

sharpshooter
05-19-2010, 02:00 AM
Savage is the one that tumbles the boltheads, not the contractor. They have taken steps to control the dish. From what I heard they are machining the bolt face smaller and re-machining after the tumbling, but this is only on the target rifles.