Gunsmithing PT&G bolt ???

[bigngreen]

So I'm wanting to build a 6.5-284, I have a Rem 7mm mag sitting around that I want to use so I want to use a PT&G bolt. I'm not wanting to ream the race way but I will do the other typical truing. I want to Cerakote all the metal work and it's going to be a precision hunting rifle.

I've never changed out a bolt so I don't know a couple things, what bolt clearance I want to run and I want to use a M16 extractor but I see I can order a M16 or M16 mini, don't know if there would be an advantage to either. Any advice would be appreciated!

 

[E. Bryant]

Re: PT&G bolt ???

I think you'll tend to find that the tolerances of the Rem700 bolt raceway vary slightly. For example, I had in hand a "standard" diameter (nominally 0.6995", I believe) PT&G bolt, in-the-white. It ran very smoothly through an untouched "G" series receiver (2011 vintage), but using the exact same bolt in an "RR" series receiver from 2012 required a fair amount of lapping just to allow it to cycle somewhat freely.

For a hunting gun, I'd tend to think that looser tolerances would be better for reliability, so getting the bolt ground closer to stock dimensions would be best if you don't want to ream the raceway. I'm going from memory here since my notes are out in the workshop, but I think that the last couple stock bolts I measured from SPS models were around 0.6975" or so. Also keep in mind that any coating is going to add to the bolt OD, so adjust accordingly.

I don't have a strong opinion on the "mini" versus "regular" M16 extractor. Just remember that you'll either need to increase the bolt counterbore in the barrel or relieve the back side of the extractor in order to give it enough room to snap over the cartridge rim when closing the bolt.

EDIT: I just ran out to the shop and measured a bolt from a stainless LA R700, and it came out to about 0.6951" at the nose and around 0.6964" just in front of the bolt handle.

 

[elephantrider]

Re: PT&G bolt ???

If you have the stock Remington bolt you can start by measuring the OD of the body on that (if you have calipers). Also keep in mind that properly applied Cerakote will add about 0.001" of thickness to the bolt body and the receiver raceway, so things will get tighter after coating.