Little calcification on switch barrels?

[Matt_3479]

I’ve been going back and fourth all over the internet and YouTube trying to get the proper information and think I may have confused myself. I’d like to know the difference between shouldered barrels, and a switch lug/barloc system. I can see the nut or barloc ring but then looking into something like curtis custom vector or impact precision action it’s showing them being threaded at home without a nut or barloc system. So is that what people mean by a shoulder barrel. A normal threaded barrel by a gunsmith (shoulder meaning where the threads end and where the meat of the barrel starts?)

What makes that more appealing (other then astetics) as for every system you still need wrenches, vice and other various tools? Technically speaking doesn’t that make every action capable of that or are people talking more so that say the impact is held to such tite tolerances that gunsmith would never need to see it to spin up a barrel and you could just swap it at home. Do you need the go/no go gauges then? I’d appreciated some clarity on the subject! I love the idea of a switch without the nut or barloc system. Is it only impact and the vector capable of that?

 

[culater]

I have this one in 308 and 300 win NO wrenches needed. Returns to your zero with no shift. Only thing I move is the windage and know my zero for both cals when i switch out the barrels. So my 308 is zero at 380 yds using 168gr smk and when I switch to my 300 win it's zero at 250 yds using 225 ELD. I've had mine for the last 18 years and still shoot sub moa. No need for gauges

 

[bluebie]

This thread has a bunch of info about various switch lug types, and pros and cons of those vs normal barrels.

 

[culater]

I don't have to worry about all that,I can and have take it my rifle down and scope off still in its rings and reassemble it and set up and shoot into the same group. No shift at all.

 

[Huskydriver]

Accuracy international ax family rifles are quick change shoulderd barrels

 

[Matt_3479]

thank you. So a shouldered barrel would be just a standard set up correct with no barrel nut or barloc nut? Just threaded barrel screwed and torqued to action through action wrench and barrel vice? So Curtis, bighorn and impact are companies capable of that? That interests me over the barloc or barrel nut.

 

[Sheldon N]

Couple of categories, each work differently.

1) Barloc and remage/savage prefits all use some sort of clamping force from the barrel nut or Barloc wedge to hold the barrel in place. All need a go gauge to set up for consistent headspace and/or need witness marks on the barrel/lug, and in the case of a shouldered Barloc the gunsmith likely needs the action in hand to properly chamber a barrel.

2) A couple actions use a screw into the side of the barrel to resist rotation. Curtis Vector and AI rifles are examples. Screw barrel hand tight onto the shoulder, tighten set-screw to keep the barrel from loosening. These barrels are made just like a traditional shouldered barrel, the only difference is that the screw holds it in place allowing you to tighten the barrel hand tight vs using a vise/wrench. These don't need a go gauge, since the shoulder against a firm lug will keep headspace consistent, just as it was set by the gunmsmith when the barrel was chambered.

3) Conventional shouldered barrels are pretty much every other action out there. Tighten barrel onto action with a barrel vise and torque wrench which holds it in place, the headspace is set by the gunsmith when they chamber the barrel, no go gauges needed. Now within this category there are a couple ways that you can torque the barrel onto the action. Main options are to either use an action wrench into action, barrel vise clamped on barrel, use torque wrench and set a higher torque value for semi-permanent long term mounting, or you can use a lower torque value, skip the action wrench, leave the action/scope in the stock and just use a product like the Ross Vise or machined flats on the barrel to screw the barrel onto the action. The second option is more conducive to frequent barrel swaps.


Now "Pre-Fit" shouldered barrels are a subset of categories #2 and #3 above. All a "pre-fit shouldered" barrel means is that all the actions out there of that type are consistent enough that a gunsmith can sell you a barrel off the shelf, headspaced and ready to go, WITHOUT needing to see your action in hand. Many actions have this capability, most notably Impact, Bighorn, Curtis and AI but also others like the RPR, Tikka T3x, Nucleus, Mausingfield. This depends somewhat on who you buy your barrels from, only a few shops are offering prefits for the latter actions.

Final thing to add is that for almost all gunsmiths they only need to see your particular action ONCE, then they can sell you as many pre-fit barrels to match that action as you'd like, based on the measurements they take. So really all a "pre-fit" gets you is not having to send your action in the first time you use that gunsmith.

 

[Matt_3479]

Couple of categories, each work differently.

1) Barloc and remage/savage prefits all use some sort of clamping force from the barrel nut or Barloc wedge to hold the barrel in place. All need a go gauge to set up for consistent headspace and/or need witness marks on the barrel/lug, and in the case of a shouldered Barloc the gunsmith likely needs the action in hand to properly chamber a barrel.

2) A couple actions use a screw into the side of the barrel to resist rotation. Curtis Vector and AI rifles are examples. Screw barrel hand tight onto the shoulder, tighten set-screw to keep the barrel from loosening. These barrels are made just like a traditional shouldered barrel, the only difference is that the screw holds it in place allowing you to tighten the barrel hand tight vs using a vise/wrench. These don't need a go gauge, since the shoulder against a firm lug will keep headspace consistent, just as it was set by the gunmsmith when the barrel was chambered.

3) Conventional shouldered barrels are pretty much every other action out there. Tighten barrel onto action with a barrel vise and torque wrench which holds it in place, the headspace is set by the gunsmith when they chamber the barrel, no go gauges needed. Now within this category there are a couple ways that you can torque the barrel onto the action. Main options are to either use an action wrench into action, barrel vise clamped on barrel, use torque wrench and set a higher torque value for semi-permanent long term mounting, or you can use a lower torque value, skip the action wrench, leave the action/scope in the stock and just use a product like the Ross Vise or machined flats on the barrel to screw the barrel onto the action. The second option is more conducive to frequent barrel swaps.


Now "Pre-Fit" shouldered barrels are a subset of categories #2 and #3 above. All a "pre-fit shouldered" barrel means is that all the actions out there of that type are consistent enough that a gunsmith can sell you a barrel off the shelf, headspaced and ready to go, WITHOUT needing to see your action in hand. Many actions have this capability, most notably Impact, Bighorn, Curtis and AI but also others like the RPR, Tikka T3x, Nucleus, Mausingfield. This depends somewhat on who you buy your barrels from, only a few shops are offering prefits for the latter actions.

Final thing to add is that for almost all gunsmiths they only need to see your particular action ONCE, then they can sell you as many pre-fit barrels to match that action as you'd like, based on the measurements they take. So really all a "pre-fit" gets you is not having to send your action in the first time you use that gunsmith.

Thank you that was extremely helpful. The one thing I have a question about is in #3. When changing torque specs doesn’t that technically change headspacing? If not why would you want to torque it more or less? Wouldn’t it be easier to just always torque it less and not have to fight it?

 

[spife7980]

Thank you that was extremely helpful. The one thing I have a question about is in #3. When changing torque specs doesn’t that technically change headspacing? If not why would you want to torque it more or less? Wouldn’t it be easier to just always torque it less and not have to fight it?

Technically, yes. Practically, no.

You would have to tighten it enough to materially deform the threads themselves. That would take a shit load of torque. I go to 80 because the difference between 40 and 80 is just a little oomph, You couldnt tell by looking at the extra rotational difference. If I were doing it frequently then the 40 would be easier to take off, I only swap when a barrel is shot out so I dont mind the extra force to remove it since Ive already got breaker bars and vices etc out and I appreciate the extra peace of mind that it wont back out. Not a very realistic fear but it doesnt hurt anything.

 

[Sheldon N]

Thank you that was extremely helpful. The one thing I have a question about is in #3. When changing torque specs doesn’t that technically change headspacing? If not why would you want to torque it more or less? Wouldn’t it be easier to just always torque it less and not have to fight it?

Yes, same as spife said above. Very little if any measurable difference in headspace between 25 ft/lb of torque and 100 ft/lb of torque on a shouldered barrel. I typically run around 30ft/lb and use the Ross Vise since I change barrels regularly. Don't need to take the action out of the stock and don't need to remove the scope. I have a traditional barrel vise and action wrench but don't really use them anymore since getting the Ross Vise.

 

[Matt_3479]

Thank you that was extremely helpful. The one thing I have a question about is in #3. When changing torque specs doesn’t that technically change headspacing? If not why would you want to torque it more or less? Wouldn’t it be easier to just always torque it less and not have to fight it?

Technically, yes. Practically, no.

You would have to tighten it enough to materially deform the threads themselves. That would take a shit load of torque. I go to 80 because the difference between 40 and 80 is just a little oomph, You couldnt tell by looking at the extra rotational difference. If I were doing it frequently then the 40 would be easier to take off, I only swap when a barrel is shot out so I dont mind the extra force to remove it since Ive already got breaker bars and vices etc out and I appreciate the extra peace of mind that it wont back out. Not a very realistic fear but it doesnt hurt anything.

Okay so with a barrel vise and action wrench and say bighorn tl3, I could get a rifle put together in 270. Wsm and later decide I want a switch barrel and swap from 270. Wsm to 300. Win mag (long action obviously) with just those tools and a torque wrench and torque it down between 40-80lbs and just start loading?

 

[Matt_3479]

Yes, same as spife said above. Very little if any measurable difference in headspace between 25 ft/lb of torque and 100 ft/lb of torque on a shouldered barrel. I typically run around 30ft/lb and use the Ross Vise since I change barrels regularly. Don't need to take the action out of the stock and don't need to remove the scope. I have a traditional barrel vise and action wrench but don't really use them anymore since getting the Ross Vise.

That sounds awesome! So how often do you switch barrels? 30lbs never seemed to give you any issues? What action are you using

 

[Sheldon N]

Okay so with a barrel vise and action wrench and say bighorn tl3, I could get a rifle put together in 270. Wsm and later decide I want a switch barrel and swap from 270. Wsm to 300. Win mag (long action obviously) with just those tools and a torque wrench and torque it down between 40-80lbs and just start loading?

Yes. Something like a viper barrel vise and an action wrench and order up a few prefit barrels.

I run a TL3 short action, have barrels in 223, various 6mm barrels, and a 7 SAUM barrel all on the same action.

That sounds awesome! So how often do you switch barrels? 30lbs never seemed to give you any issues?

I swap barrels maybe every week or two depending on what project I'm working on or which match I'm going to. No issues at all with 30ft/lb, even running the 7SAUM.

I honestly would steer you towards the short action vs the long action, just so you can play with 223. I shoot my 223 way more often than any other barrel.

 

[Matt_3479]

Yes. Something like a viper barrel vise and an action wrench and order up a few prefit barrels.

I run a TL3 short action, have barrels in 223, various 6mm barrels, and a 7 SAUM barrel all on the same action.



I swap barrels maybe every week or two depending on what project I'm working on or which match I'm going to. No issues at all with 30ft/lb, even running the 7SAUM.

I honestly would steer you towards the short action vs the long action, just so you can play with 223. I shoot my 223 way more often than any other barrel.

Awesome! I love that idea. I didn’t really realize that was a thing other then barloc or barrel but which I just don’t like the look of lol. Might work just fine but prefer the clean look of nothing between barrel and action. I’m going to talk to my smith about a few different things.

I love the idea of a being able to try a few calibers without building an entire new set up. With the bighorn using the floating bolt head it makes it super universal I suppose versus ordering an entire bolt.

If I had a better understanding I probsbly would of went with the bighorn on this build as I have one at the smith now that should be back within the week or two on a kelbly.

The reason I’m going long action is cause I want to do a 300. Win mag but also looking at something like the 270. Wsm for the 165-175 matrix and 170 Berger’s.