What is "thread-in headspacing"?

[Tiekmir]

Excuse my ignorance.

I see this advertised as a feature for the Axis XP 2 I bought. Savage makes a lot of it as something that makes a gun more accurate.

Can someone please explain it to me? I am attempting to learn everything about guns. I tried to websearch the subject but nothing explained it as if a newb was reading it.

[Dave Hoback]

All Savage Centerfire rifles use a Barrel that threads into the Action and a Barrel Nut which then mechanically “locks” the barrel in place. The headspace is set by turning the barrel into the Action(Receiver) threads. A reason many prefer Savage. It’s a very DIY friendly platform.

Has nothing to do with Accuracy other than very accurate Target rifles use very tight head spacing.

[Blue Avenger]

the barrel chamber is cut to have a set amount of the cartridge protrude from the barrel. the recess in the bolt head is made to receive that protrusion. savage chose to use an adjustable stop nut instead of a step machined stop as many others do. there bolt head also wobbles a tiny bit to self align with the surface of the end of the barrel. this allows them to set what they feel is the exactly right distance between bolt and barrel and tighten the nut, instead of close enough of the fixed stop mass produced barrels. most gunsmiths will take the time to make it exactly right also, thus custom built.

[Tiekmir]

Interesting, much thanks.

[charlie b]

It is enough of a feature that Mossberg and Ruger (RPR) have copied the setup on some of their rifles.

[Tiekmir]

So the competion is copying it? Nice. I almost bought a Ruger American but decided on the Axis XP II. I held both at a local store and just liked the Savage better.

[Dave Hoback]

Rugers are solid firearms. But not a Savage! America’s longest produced center fire rifle. Well... the Model 110 is anyway. (My choice) But the Axis is pretty durn close.

[Tiekmir]

I wish I had the cash for a 110, but the Axis will get the jobbdone next deer season.

[Tiekmir]

https://www.huntingretailer.com/gear/rifles/rifle-headspace-important

I read that article and now believe I understand headspacing. Does the "thread in" part refer to the threaded bolt nut? To be clear, in other rifles without the threaded bolt nut, the headspacing cannot be easily adjusted as the bolt nut is fixed in place. Where as Savage rifles have the threaded bolt nut between the action and the barrel that allows for easier adjustment.

Is that correct?

[Dave Hoback]

I wish I had the cash for a 110, but the Axis will get the jobbdone next deer season.

Oh I understand completely. Money is NOT my strong suit. I’m simply blessed enough with a knowledge base & skillset. I purchased my current 110 on Gunbroker for $270. And over time I, little by little, I picked up the parts to build.

The Axis is a fine rifle. Probably one of the top selling rifles today. Dollar for dollar it’s damn hard to beat.

[Dave Hoback]

The Savage Barrel has no shoulder. Take a Remington for example. It threads into the Action & bottoms out on the Barrel SHOULDER. Therefore, a lathe & Reamers are needed to cut the barrel/chamber for proper headspace. A Savage Barrel has NO shoulder, so it can thread into the Action until proper headspace is achieved. Then the Barrel nut is torqued against the Action surface, locking the barrel in place. The AR15 is similar, although the barrel simply slides into the upper receiver via the barrel Extension, which IS shouldered. Then the barrel nut in this case, screws onto the upper receiver itself.., again, mechanically LOCKING the barrel in place.

Many ‘smiths and shooters still argue it’s less accurate. I beg to differ. I don’t believe accuracy potential is given any creed either way by the means of barrel to Action attachment. But, can’t blame gunsmiths for trying to keep the business for themselves. Very similar to many KNIFEsmiths who hate me because I make high performance knives with high alloy steel, via stock removal. Knives that are much, MUCH better than the forged JUNK steel most smiths use. Mainly 1084. LOL! But I digress.

[Tiekmir]

Uh, so how does the shouldered round shoulder in the chamber of a Savage rifle if it has no shoulder inside? I get how your Remmington example works, but I am fuzzy on the Savage one.

Also, you forge knives by what? I have never heard of this "stock removal" process.

[Tiekmir]

the barrel chamber is cut to have a set amount of the cartridge protrude from the barrel. the recess in the bolt head is made to receive that protrusion.

I think this is the answer. Right?

[charlie b]

A bit of confusion there. A shouldered barrel like the Remington seats against the face of the receiver. Then a chambering reamer is used to cut into the barrel until the proper headspace is set.

The barrel nut type has no shoulder on the barrel, just the jam nut, so it can be adjusted in and out to get the proper headspace. FWIW, the only Ruger that I know with this feature is the Ruger Precision Rifle (RPR).

Shouldered cartridges are just a type of cartridge. Other types are rimmed (such as .30-30 or .45-70) and those that seat on the case mouth (such as .45acp pistol). The shouldered cartridge has a matching chamber cut into the barrel. The shoulder of the cartridge meets the matching portion of the chamber and that determines how deep the cartridge will go into the barrel.

So, we are talking about two different shoulders here. One is on the outside of the barrel. The other is on the cartridge and inside the barrel.

(someone should find a nice cutaway picture of the different barrels and chambers) :)

[Dave Hoback]

Uh, so how does the shouldered round shoulder in the chamber of a Savage rifle if it has no shoulder inside? I get how your Remmington example works, but I am fuzzy on the Savage one.

Also, you forge knives by what? I have never heard of this "stock removal" process.

Sometimes a picture is worth 1000 words. Here is a Shouldered barrel.
https://i.ibb.co/pnQjV4S/9-A9-BC323-E2-D8-4243-9-A18-4-B96-A0-C4-BB6-C.jpg (https://imgbb.com/)

This is a Savage barrel which is just threaded. The barrel nut threads onto the barrel & the barrel threads into the Action. Then the barrel nut is UNTHREADED until it STOPS against the Action.
https://i.ibb.co/J34nyBb/E3-C73835-21-EF-4580-89-B7-8-D17-D281-B6-A9.jpg (https://imgbb.com/)
It doesn’t have anything to do with the chamber.


BTW. I don’t forge knives. Stock removal is the term used for machining blades. I take a flat piece of steel & machine/grind it to shape. Modern high alloy steels CAN’T be forged. ALL high performance knives are made like this because of the steel used.

[Mr.Snerdly]

It is enough of a feature that Mossberg and Ruger (RPR) have copied the setup on some of their rifles.


Also Marlin and now Remington with the 783 which is pretty much a Marlin X7. I think it is a little bit cheaper to produce and the accuracy was something they weren't going for originally but it seems to have worked out well for everyone.

[Dave Hoback]

Yes, and there are companies like Bugholes that do prefit, Top-Tier barrels and have their own barrel nut style, offered for almost ANY Action! Even if I was going to build a Tikka, Remington, Howa or even a custom Action, I’d be using their barrel nut. While having had access to a lathe in the past, I need longer do. And I don’t have the space in my shop room to fit a proper sized lathe for barrel work. I also do like the control of headspace.

[Robinhood]

I would choose a Ruger American over a Axis anyday of the week. A lathe and barrel work are two fisted burgers Dave. Hopefully your cerakote setup will help you get more barrels without having a lathe.

[Dave Hoback]

Hmm..most things I do should be two fisted. But I seem to do ok with just the one. Thing I tell people is put a hand in your pocket when you wake. See how long you last before you use it;)

“Cerakote setup getting me more barrels without a lathe” Ya lost me on that one Robin??

[Tiekmir]

Sometimes a picture is worth 1000 words. Here is a Shouldered barrel.
https://i.ibb.co/pnQjV4S/9-A9-BC323-E2-D8-4243-9-A18-4-B96-A0-C4-BB6-C.jpg (https://imgbb.com/)

This is a Savage barrel which is just threaded. The barrel nut threads onto the barrel & the barrel threads into the Action. Then the barrel nut is UNTHREADED until it STOPS against the Action.
https://i.ibb.co/J34nyBb/E3-C73835-21-EF-4580-89-B7-8-D17-D281-B6-A9.jpg (https://imgbb.com/)
It doesn’t have anything to do with the chamber.


BTW. I don’t forge knives. Stock removal is the term used for machining blades. I take a flat piece of steel & machine/grind it to shape. Modern high alloy steels CAN’T be forged. ALL high performance knives are made like this because of the steel used.

Thanks. That helped a lot.