The Original CZ Forum

CZ LONG ARMS => CZF RIMFIRES => Topic started by: BobC on February 23, 2021, 05:34:58 PM

Title: torque settings for cz457 varmint mtr
Post by: BobC on February 23, 2021, 05:34:58 PM
hi...i’m looking for the torque settings for the 2 barrel allen screws, that secures the barrel in place...i’ve watched the you tube vid from cz usa and can’t quite get what he is saying...thanks..

bob
Title: Re: torque settings for cz457 varmint mtr
Post by: david s on February 23, 2021, 07:15:52 PM
CZ has listed 5 Newton meters or 44 inch pounds, this is considered by quite a few people as being on the high end of things. Lilja  barrels recommends 35-40 inch pounds for there barrels. The concern is that the barrel/chamber thickness above the area that the two set screws press against gets pretty thin and you don't want to inwardly bulge the chamber with the screws. Torque readings are taken with dry threads on both the receiver and set screws and any lubes even LocTite will give a lower reading than it really is compounding things. Quite a few people recommend trial and error approach of starting low and gradually increasing the torque until things settle down, this can be a pain in the elbow at the range though. Good Luck.
Title: Re: torque settings for cz457 varmint mtr
Post by: BobC on February 23, 2021, 08:35:13 PM
thank you, appreciate the info....
Title: Re: torque settings for cz457 varmint mtr
Post by: BillG56 on April 25, 2021, 09:07:13 AM
I can't remember where I read this but it's similar to what David stated above.  Some shooters back those screws out to a lower torque setting of around 20 in-lbs then work up 5 in-lbs at a time till they find the sweet spot, often around 35 in-lbs.  HTH.
Title: Re: torque settings for cz457 varmint mtr
Post by: Joe L on April 25, 2021, 10:43:37 AM
I set mine yesterday at 30 in-lbs dry.  They were definitely tighter than that from the factory, probably at the 44 in-lb spec.  Same 30 in-lbs for the magazine screw, after the barrel grub screws.  Also 30 in-lbs on the action screws, a little at a time.  The action fits the stock well and I am not going to mess with it further.  I will check the screws every few months, however.
Joe