I have a Husqvarna in 8mm and it has excessice headspace. I have tried four different mauser bolts and all will close on the no-go gauge. I was thinking of pulling the barrel and having it rechambered for 8mm06 but got to thinking that if the rifle has setback it probably should have the action re hardened. Where does on get that done? I don't want to set back the barrel or rebarrel as the barrel has nice iron sights on it and is rolled with the Husqvarna logo. Also, it just says 8mm on the top of the barrel. I have measured a fired case it it seems to be 8x57, not 8x60. Any help would be appreciated. Mori

I believe the barrel can be set back and maintain TDC on the sights.

I ain't a gunsmith.

IIWY I'd first pull the barrel and examine the receiver's inner recoil surfaces for setback. If setback is there, remachine the surfaces square and flat. In any case, set the barrel back one turn and rechamber.

There are several ways to check for setback without pulling the barrel but solving the excessive headspace problem will require it anyway.
Regards, Joe

I would SERIOUSLY consider investing in an 8x60 and an 8x60S cartridge case...it may very well be that you do in fact have one.

The 8x60, as you know, lengthened the case body by 2mm and the case neck by 1mm to give an overall length of 60mm.

If you can't get an 8x60 case then maybe try to glue a dime or 2mm washer on the base of a correct size 8x57 case and see if it chambers in the gun!

Just remember to remove your extractor AND extractor collar from your bolt!

If you strip the barrel and action from the stock see if there are any proof markings underneath in the part usually covered by the furniture.

Hope it helps!

What other indications of excessive headspace?

Whose no-go gauge did you use and what are it's dimensions? There are at least 2 versions of the 8X57 gauges.

Get a Field gauge and check the head space and then make a decision.

quote:

Originally posted by enfieldspares:
I would SERIOUSLY consider investing in an 8x60 and an 8x60S cartridge case...it may very well be that you do in fact have one.

That would be neat considering Husqvarna did not offer an 8x60.

Not to worry. Unless you find obvious signs of excessive headspace in the fired cases (protruding primer etc). Just know that these rifles were chambered long before SAAMI specs and may vary from your SAAMI no go guage.

A friend loaned me a factory 8x60 round to try and it won't begin to go completely into the chamber, so it is not a 8x60. Yes, I do have some protruding primers after firing. If I have the the set back machined , wouldn't it require having the action rehardened? On the headspace gauge question, I will have to look at them (I borrowed them from my friendly gunsmith) to see what brand they are. Mori

Mori,

The procedure to set headspace isn't to machine the action, it's to machine the barrel. Think of it this way: The barrel is an expendable part, the action is re-usable.

To do so, the gunsmith measures the thread pitch, and faces the shoulder of the barrel off by an amount equal to one turn of the barrel. That way, the sights come out on top. Then, the back of the barrel is faced off by the amount needed to seat on the inner mauser shoulder. Then, a headspace gauge is inserted, and the depth checked. The chamber is re-reamed to the depth required to put the headspace within spec.

Not a difficult or expensive process to do. It's routine for most gunsmiths. On a mauser, at 12 tpi, one turn = .083", or about 1/16". Not enough to even mess up the fit of the barrel channel in most cases.

As posted before, make sure that you find out why the headspace is excessive, and change that if needed.

An alternative to doing any of this is to fireform cases to fit the chamber, then only neck size them after that. Then, you don't have an excessive headspace problem.

Now, a comment on your protruding primers. Protruding primers are often caused by too low of pressure, not excessive headspace. Most of the time, primers back out a bit when the primer goes off, as the primer gases try to get through the small flash hole. Then the chamber pressure increases as the powder ignites, and that forces the casing back against the bolt, reseating the primers. If the cartridge is loaded to very low chamber pressure, it doesn't reseat the primer so the protrusion is seen.

Excessive headspace to me is normally indicated by a primer that is excessively mashed or deformed onto the shoulder of the primer pocket, without other signs of excessive pressure. That is caused by the primer backing out, then expanding because of lack of side support, then being mashed back flat by the case pressure forcing the brass back against the bolt.

If I just had primers backing out and no other signs, I wouldn't worry about excessive headspace, I would just shoot the rifle. On the other hand, if you're blowing out primers, exhibiting deformed primers like I described above, have brass stretching to the separation point, or having primers not go off because the firing pin doesn't reach them, then you might worry about excess headspace.

Postscript on the above after thinking about it. I'll look when I get home and see if I have a field gage in 8x57. If I do, I could mail it to you to try. I think I have one, but may have sold it as I don't have an interest in the 8 x 57. I went through my reamers and gages last winter and sold a lot of them that I never use.

dave

If you reload your ammo just long seat your bullets to engage rifling to hold case back against the bolt and fire form them to the chamber. Then when you load them again just be sure to back your sizing die off the shoulder so you don't set it back. Happy days! If lugs are set back you will probably notice hard bolt lift with normal loads then you have a problem.

If your bolt closes on a no-go gage then you have excessive headspace. IMO, a field gage is nothing more than a feel good device for those who would otherwise cry because their rifle has excess headspace.

quote:

That would be neat considering Husqvarna did not offer an 8x60.

Thank you for your input.

It is of course also totally unlikely that the rifle was not at some time re-chambered to 8x60S as equally Mauser also never offered their Model 98 or 98K in 8mm-06.

I have seen scores of 8x57 military and sporting rifles by ALL makers re-chambered to 8x60 for import into Belgium and France when 8x57 was a prohibited calibre.

quote:

Originally posted by enfieldspares:

Thank you for your input.

It is of course also totally unlikely that the rifle was not at some time re-chambered to 8x60S as equally Mauser also never offered their Model 98 or 98K in 8mm-06.

I have seen scores of 8x57 military and sporting rifles by ALL makers re-chambered to 8x60 for import into Belgium and France when 8x57 was a prohibited calibre.

Thank you. I felt relatively safe making such an outrageous statement, especialy since the OP stated:

quote:

I have measured a fired case it it seems to be 8x57, not 8x60. Any help would be appreciated. Mori

Mori,

I checked, have a go and a no go but no field.

I reread your post, I see you were talking about the setback on the bolt, not setting back the barrel.

If you re-heat treat, the company is Pacific Metallurgical, Kent, WA. If the bolt is setting back and you correct that, you certainly should re-heat treat. If you do, get 9 friends to go in with you on the project. The cost is the same for 1 or 10.

dave

quote:

Thank you. I felt relatively safe making such an outrageous statement, especialy since the OP stated:

quote:
I have measured a fired case it it seems to be 8x57, not 8x60. Any help would be appreciated. Mori

Ah well...there's measuring and there's measuring!



But I have seen so many things where chambers have been modified that I never rule out any possibility once the obvious has been ruled out.

But I take you point in the good humour that it was received.

Still get here, saw one six weeks ago, Smith & Wesson British WWII Contract revolvers where the cylinder has been reamed from .38 S & W to .38 S & W Special even!

Less and less but they still turn up just enough to cause problems.

This one came out of South Africa and was being, unknowingly, offered as still being chambered in .38 S & W in a very respectable British auction house.

And the old chestnut of the .455 Webley with the back cylinder face machined to allow .45 ACP with a half-moon clip.

Or also reamed out to take .45 Colt cases..that you do see more often.


France is a source for some real "odd ball" chamber conversions such as the 7.62mm Moisin-Nagant rifle machined out to de-militarise it to use a .348 Winchester case necked to 7.62mm plus of course the 8x60.

I tried another bolt and it also drops on the Forstner no-go gauge, but feels snug and tight in the action. I put some Dykem blue on the bolt lugs and they both are bearing (blue rubbed off) on the lug seat. So , next I will pull the barrel so I can see and measure the set back. Thanks for the heat treating info- I will contact them . Mori

If this rifle was built on a 96 action I guess there could be setback. If it was built on a FN action and there is setback it will qualify for Ripleys "Believe it or Not". Only time I have observed set back on a FN was when it was chambered for something extreme (8X68, 6.5X68. 300 Weatherby, 300 H&H).