Finding top dead centre?

gstprecision

New member
Just curious how you guys mark top dead centre when installing a muzzlebrake?

I normally use a string through the aft scope base screw hole. I line up all the hole with the string and mark TDC on a piece of masking tape before removing the barrel.

Today I used a magnetic laser level shooting a straight line attached (to a metal piece) above the barrelled action. Lined up everything ( the 4 base screw holes) then marked the front on the masking tape.

I am sure there is many ways of doing this, just trying to figure out what works best.

GST
 
What works best is what works for you. They are never perfectly aligned so I pretty much eye ball it stopping just short as it will rotate a little further with removal.
 
Clamp action to a 90* angle plate(Mauser), or v-block on its side(Rem.), place on surface plate. Use height gauge to find the center of the muzzle; scribe inconspicuous TDC line on the end of the barrel. Many ways to do it. Depends upon what you consider to be the rifle's baseline, and/or what tools you have on hand.
F1
 
Scribe a line

Install barrel on action and put Dykem at the breech and muzzle. Use a square to scribe a line at TDC. Remove barrel and mount between centers in the lathe. Put a spring-loaded scribe in the tool post, align with the scribed line at the breech - move carriage to the muzzle and scribe the alignment line.
 
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