broaching vrs. barrel extension

[clinton]

i was wondering if someone could explain to me the pro's and con's of locking the bolt into a barrel extension instead of broaching the receiver and locking it into the front of the receiver. it seems that most if not all the benchrest guns use a broached receiver, so that must be more accurate. but why?

 

[jackie schmidt]

Clinton

Two of the more popular Benchrest Actions, the Kelbly Panda and the Stiller Viper have what could be called a "barrel extension". It is a high tensil strength insert that is locked into the reciever and holds all of the pressure of the ignition.

If you removed that insert from either action, and screwed a barrel onto it, inserted a bolt, and figured out a way to hit the primer, it could be fired safely.

Not much different from the barrel extension found in the AR design.

The advantage that Benchrest Style action has is that the insert is permantly locked into the rest of the action body, achieving a substantial amount of barrel support. When the barrel is installed, the entire assy becomes, more or less, one solid unit.

One other thing, too. The modern bolt action, (not changed that much from the originol Mauser design), is amazingly simple to manufacture after all of the tooling cost and set-ups are taken care of. Not many moving parts, and amazingly efficient......jackie

 

[clinton]

do the Kelbly Panda and the Stiller Viper still broach the full length of the receiver or is the bolt ( or the bolt carrier as in the ar-15) a larger dia. than the locking lugs so that the lugs never touch the inside of the receiver?

 

[jackie schmidt]

Clinton

As with 90 percent of Benchrest Actions, the Viper and Panda still use a regular 2 lug bolt.

The Hall and 3-lug Bat are two popular 100-200 yard Benchrest Actions that fearture a full diameter bolt body with same diameter lugs..........jackie

 

[Don]

i was wondering if someone could explain to me the pro's and con's of locking the bolt into a barrel extension instead of broaching the receiver and locking it into the front of the receiver. it seems that most if not all the benchrest guns use a broached receiver, so that must be more accurate. but why?

Not more accurate.

Weight and ease of manufacture.

Steel insert/extension in an aluminum body.

 

[clinton]

does the greater expansion of the aluminum receiver over the steel barrel expansion have an effect on accuracy?

 

[Boyd Allen]

If you look at past performance, evidently not.