Gunsmithing How Do I Set the Proper Head Space

[Cat64]

Soon I will have received all the necessary components to assemble a factory Savage 12 target rifle in a 6 mm BR. I asked the supplier about determining headspacing and I was told that "When your barrel is installed your head spacing will be the Go Gage plus .001 –.0015".
My question to you guys is, what is the best method to ensure I have achieved that fine of a headspace. I know that the common sense approachis to use the Go/NoGo gages but I believe the difference between those two is greater than the above measurement. Do I even need a NoGo gage? I saw a fewYouTube videos where some smiths are using Scotch Magic Tape at the end of the Go gage to assess the proper measurement. However the tape is 0.0022 thick...so I am in a quandary. I need some direction please.

 

[wayfastwhiteie45]

post deleted.

 

[EXTREMEPREJUDICE]

I need some direction please.

If you want "fine" (your terminology) headspace all you have to do is remove the ejector and firing pin from your bolt, put in your GO gauge screw your barrel into the receiver until it is tight against the bolt face and tighten the lock nut. You'll have set your headspace to least amount based on the type of gauge you have (SAAMI, etc.) Then remove bolt, put in a .001 piece of shim stock in between the bolt face and go gauge and attempt to close the bolt, it should not close. If for some reason the bolt will close, take out the shim shock, loosen the barrel nut, tighten the barrel a tad tighter against the go gauge and repeat the process. That will allow you to have a .001 headspace variance for ammo tolerance. If you want a greater variance, use thicker shim stock. I'm not too crazy about tape............YMMV. I'm not a gunsmith, this is how "I" would do it!

 

[Straight Shooter]

That way will work fine. The tolerances you are working with will have no affect on accuracy or safety. Many guys will set it against a new brass and tighten it up. It's fully adjustable. Like a giant micrometer with a lock nut. You could even make up an index tape for the action and an index mark on the barrel marked out in thousandths or half thousandths depending how fine your lines are to make adjustments. It would look like a big torque wrench. Lightly hand tighten up on the go and stick the tape down on zero. Remove the gauge and dial in your headspace. If I was doing up a switch barrel I for sure would be using index marks.

Right up front. Never tighten any barrel or nut with the head space gauge in place. Never force the bolt shut on a gauge. It will crush right into your chamber. Always remove it when using tools to tighten things up.

On a Remington style to get .001" in the shop we get it to just close on the Go, plus 1 layer scotch tape. Then torque to 100 pounds. To confirm, clean the Go gauge of tape and reinstall. Then measure the bolt thrust clearance with a magnetic base tenth indicator. To get zero head space I get it to close halfway on one layer of tape. The torque up. The crush takes up the .001 and I am left right at zero.

On a Savage with the nut tightening the nut pulls the barrel out from the receiver. To get .001" I think I would set the barrel lightly on the go gauge with the bolt shut and then tighten the nut up hard. Double check the bolt thrust clearance with a tenth indicator and go from there. If you need it moved from there I would use reference marks rather than the gauge.

 

[Capt Beach]

Good advice there guys...Cat64 is on his way to setting up a very nice rifle...