Rem 700 Bolt binding problem

[pburton]

Last year I had a 300 win mag built on a 700 action. As part of the build I ordered a PTG bolt. The gunsmith that built the rifle said that he had experience with PTG bolts. When I received the rifle, I noticed that the bolt ran smooth when chambering a round or closing the empty bolt. But, when I open the bolt it was difficult to draw back with any sort of pressure on the bolt handle or knob. When the bolt is open completely there seems to a lot of up and down movement. The rifle shoots really well, but the bolt is driving me crazy. Quick follow up shots are almost impossible. I spoke to the gunsmith about this and his answer was it was due to the Cerakote. I told him that I did not think that this was the case. He offered to look at it, but now I am nervous to send it back to him. Thoughts and what should I do?

 

[Dosh]

p, if it was Cerakoted the coating may bind until you work the bolt, cycling it for as long as it takes to become smooth. I recently had a Rem 700 back from Cerakote and it took a couple hours of spare time to break in. Keep the lugs lubed during this process.

 

[pburton]

I thought that this may be case initially. I have put nearly 100 rounds through the rifle and expected the problem to start improving, but it has not. There is wear through the coating on the lugs.

 

[Georgiashooter]

It really shouldn't have been coated on the lugs. Is your smith pretty experienced? I don't see much sense in truing action/locking recesses and bolt locking lugs just to coat them, that's just me tho. I use to have a buddy cerakote my stuff and had a bolt binding like you describe. I put it in lathe and "polished" the coating with 600 grit. I've also had a PT&G bolt on a 6 dasher build that wanted to bind with no coating, turned out the anti bind groove on bolt was too tight. Lapped it in and worked fine. I suspect that is trouble you are having.

 

[pburton]

The bolt was not Cerakoted. It came from PTG with the lugs blued. The bluing is what is worn on the lugs. I think that you are right with the anti bind groove. Is lapping it something that I could do? Or is this something that I should send to someone to do? Thanks for the help!

 

[Georgiashooter]

I gotcha, I read coating and assumed.... we all know how that works. Yes you can lap it with some lapping compound from brownells. I used 600 grit cause that's what I had but 400 or so would be better. If there's any way to make sure that's the problem would be good. I ended up disassembling the rifle and looking into bottom of action with a light and magnifier. Hope this helps

 

[pburton]

Thank you very much! That helps a lot.

 

[parshal]

Did you get this worked out? Depending on how tight the bolt is any cerakote in the raceway can cause binding like you describe. I've used lapping compound like Georgiashooter recommends. It smoothed things out fairly quickly.

 

[Hired Gun]

On a factory 700 there is usually about .007"-.009" bolt to action clearance. Cerakoting the bolt body and inside the action works like sleeving the bolt. It takes up about .004" clearance doing those surfaces. If the new bolt is too big and the inside of the action is coated in certain spots it can make the fit too tight. Done right Cerakote takes forever to wear out of a spot like this. It's fairly easy to see by a trained eye. Putting lapping compound in there is going to leave some pretty ugly scars.

When coating a bolt you always want to do the lugs. The Cerakote works like a dry lube and helps prevent galling. If it is hard to pull back with a fired round but easy with nothing in it sounds like the bolt nose relief is not big enough and the M-16 extractor may be dragging in the barrel. The PTG bolt with M-16 extractor on magnum applications needs a bigger bolt nose relief.

If that is not it look at the slot the firing pin sear rides in on the rear tang of the action. Sometimes if they are sharp edges it will not want to come back through that slot very easy.

Another thing that can cause it to feel like this is damage to the action from the action wrench. All the different styles are capable of damaging an action. Again a trained eye will be able to pick up on this.

Hold off on the home remedies or plan on taking full responsibility for the damage. Your smith cannot be expected to correct for free what someone else has done to it. I'd say give your smith a chance to remedy the problem. That will be your most economical solution. From machine work to part replacement whatever it takes to cure is on him. If you let someone else work on it of grind on things yourself he is off the hook.