Effects of Bolt Locking Up In The Barrel

[South Pender]

A number of newer bolt-action rifles have the bolt lock up in the barrel, rather than the more-common pattern of locking up in the receiver. Examples that come to mind are the newer Anschutz centerfire rifles and the new line of Schultz & Larsen switch-barrel rifles, but there are many more, particularly the switch-barrel brands, with this newer feature.

So I’m curious about the advantages and disadvantages of this newer design. Obviously, fitting a new after-market barrel the traditional way is precluded, although many of these brands provide replacement barrels that drop right into the actions. I guess I’m most curious about the effects, if any, on accuracy potential. Does the lock-up in the barrel ensure greater in-line conformity between bolt and barrel—and, as a result seated cartridges in better alignment with the barrel perhaps resulting in superior accuracy? Are there any strength issues favouring one over the other? Is barrel-steel hardness a factor?

What are your thoughts?

 

[m1008]

It’s not a new feature. Common or popular models have extensions available or you can cut it off an existing barrel when shot out. Once manufacturing ceases your sorta outa luck for barrels.
Poor factory support is why they commercially fail.

Some countries in Europe have limits on number of guns owned.

 

[iron cat]

It’s not a new feature. Common or popular models have extensions available or you can cut it off an existing barrel when shot out. Once manufacturing ceases your sorta outa luck for barrels.
Poor factory support is why they commercially fail.

Some countries in Europe have limits on number of guns owned.
View attachment 890870

Sportcos by Omark are another brand that lock up in the barrel. When rebarreling, there are several outfits that make adapters for a standard style of lock up. Jim Dugan out of Saskatoon makes adapters for them .
IIRC the Mauser 66 also locks up in the barrel, I may be wrong though .
The Remington 710 ( 770 maybe?) did as well.
GREAT looking Sauer BTW!
Cat

 

[Suther]

It can't be that detrimental if so many semi auto platforms do it too?

 

[I Dont Care About You]

Strengthwise it wouldn't make any difference.

Likely the biggest reason and benefit is that it ensures headspace is correct, especially for rifles with removable barrels.

 

[BlackPowderBurner]

It’s an excellent system that dates back at least to Louis Shlegelmilch in the 1890’s. In the purest form, the receiver becomes merely a point to mount the trigger/sear, guide the bolt, and seat the magazine allowing for a very light skeletonized action.

 

[jbmauser]

Sportcos by Omark are another brand that lock up in the barrel. When rebarreling, there are several outfits that make adapters for a standard style of lock up. Jim Dugan out of Saskatoon makes adapters for them .
IIRC the Mauser 66 also locks up in the barrel, I may be wrong though .
The Remington 710 ( 770 maybe?) did as well.
GREAT looking Sauer BTW!
Cat

Is Jim still in business?

 

[iron cat]

Is Jim still in business?

Yes he is.....
Cat

 

[conor_90]

I think with alloy actions this could be the future for ultralight guns allowing them to be either insanely light, or current weights with heavier profile barrels (balance issues though, this seems to be a thing in my handling of the cz alphas)

 

[maple_leaf_eh]

From the Interwebs:

Dugan's Gunsmith E · Map · 501 45th Street E Saskatoon, SK S7K 0W3. (306) 933-0606.

 

[Canuck65]

A number of newer bolt-action rifles have the bolt lock up in the barrel, rather than the more-common pattern of locking up in the receiver. Examples that come to mind are the newer Anschutz centerfire rifles and the new line of Schultz & Larsen switch-barrel rifles, but there are many more, particularly the switch-barrel brands, with this newer feature.

So I’m curious about the advantages and disadvantages of this newer design. Obviously, fitting a new after-market barrel the traditional way is precluded, although many of these brands provide replacement barrels that drop right into the actions. I guess I’m most curious about the effects, if any, on accuracy potential. Does the lock-up in the barrel ensure greater in-line conformity between bolt and barrel—and, as a result seated cartridges in better alignment with the barrel perhaps resulting in superior accuracy? Are there any strength issues favouring one over the other? Is barrel-steel hardness a factor?

What are your thoughts?

I suspect the advantage is for the manufacturer, not the consumer. Factory assembly would be way easier, headspace will always be consistent in a production run, receivers can be made of cheaper and softer materials, etc.

That doesn't mean they're not as good. Roessler and Mauser have straight-pull actions that work this way, and they're really excellent. Anschutz is certainly not a bargain brand. Also, think about how many shotguns and AR-type rifles work this way. It's definitely not a new idea.

 

[Denver Steve]

Chapuis ROLS rifles have a very unique way of the bolt locking into the barrel, which is very strong. They test them up to 123,000psi. Strongest bolt action rifle ever made I believe. Here are some pics of mine.

 

[South Pender]

Chapuis ROLS rifles have a very unique way of the bolt locking into the barrel, which is very strong. They test them up to 123,000psi. Strongest bolt action rifle ever made I believe. Here are some pics of mine.

There have been other bolt actions tested that have survived that pressure. The H.P. White laboratories tested the Schultz & Larsen action (used in their M54J, M60, M65, M68DL rifles) in the 1960s, and it withstood 129,000 PSI pressure. The Fortner system used in the Heym SR30 has been tested to 110,000 PSI without any problems. The Blaser R8, with its 14-lug radial collet lockup was tested at the DEVA Association laboratory in Germany and has withstood 210,000 PSI pressure.

 

[m1008]

Chapuis ROLS rifles have a very unique way of the bolt locking into the barrel, which is very strong. They test them up to 123,000psi. Strongest bolt action rifle ever made I believe. Here are some pics of mine.

Doesn’t look or seem unique looks like a collet

 

[guntech]

I think the integral lugs systems are a production benefit to the manufacturer... pain in the ass for after market barrels.

Has anyone a picture of a Remington 700 where the action failed because of excessive pressure? I have never seen one.

 

[South Pender]

I think the integral lugs systems are a production benefit to the manufacturer... pain in the ass for after market barrels.

Has anyone a picture of a Remington 700 where the action failed because of excessive pressure? I have never seen one.

If by "integral lug systems" you mean the bolt locking up in the barrel, the benefit is not to handle higher pressures, but instead is primarily in the production of switch-barrel rifles that make it easy to swap out barrels. You don't "rebarrel" these in the normal fashion with the usual after-market barrels, but instead purchase the different drop-in barrels from the rifle manufacturer you want when purchasing the rifle. My Schultz & Larsen Victory rifle came with 243 Win. and .270 Win. barrels, and alternating between these two barrels is about a 10-minute operation with nothing more than an Allen key.. I plan to add a 9.3x62 barrel at some point. If I ever shoot out one of my barrels (extremely unlikely), it will be easy to replace it with another chambered for the same cartridge. All the barrels fit the same receiver and have approximately the same contour and, as a result, match up well with the barrel channel in the stock.

 

[guntech]

I stand by what I wrote... a production benefit to the manufacturer... and pain in the ass for after market barrels.

The manufacturer is set up to mass produce the barrel assembly and can do it efficiently and markets these replacements at a considerable price.

For any owner or gunsmith wanting to fit a custom barrel it is a pain in the ass and costly.

Conventional barrels and actions are considerably cheaper to replace a barrel.

 

[05RAV]

I stand by what I wrote... a production benefit to the manufacturer... and pain in the ass for after market barrels.

The manufacturer is set up to mass produce the barrel assembly and can do it efficiently and markets these replacements at a considerable price.

For any owner or gunsmith wanting to fit a custom barrel it is a pain in the ass and costly.

Conventional barrels and actions are considerably cheaper to replace a barrel.

CZ cancelled the barrel exchange for their CZ 600 series in which the bolt locks in the barrel. There was an accident when the CZ tester was seriously injured:

. CZ recalled all the CZ 600 rifles for fixing the problem: "Česká zbrojovka (“CZ”) has recently learned of a potential safety issue with the CZ 600 bolt-action rifles. CZ is voluntarily initiating a recall of these rifles in order to protect the safety of its customers because of the potential for failure if the barrel is not installed correctly" (https://www.czub.cz/en/support-recall/)”.

 

[m1008]

CZ cancelled the barrel exchange for their CZ 600 series in which the bolt locks in the barrel. There was an accident when the CZ tester was seriously injured:

. CZ recalled all the CZ 600 rifles for fixing the problem: "Česká zbrojovka (“CZ”) has recently learned of a potential safety issue with the CZ 600 bolt-action rifles. CZ is voluntarily initiating a recall of these rifles in order to protect the safety of its customers because of the potential for failure if the barrel is not installed correctly" (https://www.czub.cz/en/support-recall/)”.

If that’s a true story it’s a retarded design if it can be assembled wrong

 

[Denver Steve]

Doesn’t look or seem unique looks like a collet