CFW-A Bolt Maintenance / Wear

[yticllik]

Hey guys,

I noticed some wear on the sear catch for my CFW-A bolt. I just wanted to make sure it doesnt get worse. Can someone tell me if it looks normal and what I can do to ensure it doesn't get worse? I read the bits on filing it down to bring it more square, but how much can i do that before it causes problems? I'm using a Lage sear fwiw. Also, I had thought about cutting some coils off the orange spring in an attempt to reduce the force.

Thanks!

 

[Hey...]

Mine was similar initially but oddly enough it seems to have stabilized. I filed off the burr/edge. Doesn’t seem to be peening the same as it did when new.

Logically thinking there is a lot of distance that sear notch can be moved backward from wear and still not affect picking up another round.

I accidentally dropped my bolt from a low height and the corner was dented quite easily. Steel wouldn’t have had a mark so it got me worried if the machined firing pin will wear down quickly hitting all those primers. I’d say I have 3k+ round through this bolt and the fired primers still look the same (that I can remember) as when the bolt was new. Should the day ever come when the firing pin is too worn I’m sure a steel firing pin can be drilled from the back and pinned in place.

So in a nutshell the alloy is unique and can give reasons to worry but in real world use it should last countless tens of thousands of rounds before any gunsmith repairs are needed.

 

[A&S Conversions]

Something to keep in mind, the tungsten alloy is is very dense but has a very low steel percentage to allow the alloy to be mechinable. Pure Tungsten is brittle and very difficult to machine so some steel is added for machineability. Tom had told me that the company that machined the bolts could only get three bolts from one set of tooling because of the density of the alloy.

Just a thought, would it be worth while developing a replacement sear that is softer than the the Tungsten alloy? Maybe softening the heat treatment to a standard sear? That way the cheap part (the sear) could be replaced instead of damaging the very expensive part (the $1,000 Tungsten bolt). I would think having an inexpensive throw away part would be preferable to repairing a very expensive bolt.

Scott

 

[yticllik]

Thanks for the feedback guys. I was thinking the same thing about the sear. Definitely an interesting approach. I don’t own any of the proprietary Lage bolt uppers so I rely on the CFW as my go-to. Knowing that I can’t get another easily makes me weary of damaging it. Was thinking about picking up another Lage upper to beat on and save wear on the CFW bolt.

 

[RevolverJockey]

Kinda seems like dovetailing in a harder sear engaging piece seems better than putting in worse sears. The sear kinda needs to be hard for a reason.
Lee

 

[A&S Conversions]

Yes, a hardened tool steel sear surface in the bolt would be best. But would adding a tool steel surface to the tungsten bolt, solve the problem? Would adding such a tool steel part have enough of a bearing surface that the bolt would not deform behind the tool steel part. My question is, who would want to design, build, and install such a part? I have heard of these tungsten bolts selling for twice the original retail price. Tool steel work is a niche all to itself. There are also very few that work with tungsten alloys. So someone familiar with both that would do a one off or very limited quantity would sound pretty difficult to find. Even if you could find someone, what would the cost be?

On the other end, buying a few standard sears and bringing them and the bolt to a shop that does heat treatment and tell them that you want the sear surface of the sear to be a little softer than the tungsten bolt, so the sear wears instead of the tungsten bolt sounds a little easier to achieve. I would rather throw a way some custom sears that were $100 each after they wear out, than to fund such a niche project that would be next to impossible to find someone competent to do the work on a tungsten alloy bolt. Maybe I am missing something?

Scott

 

[sniperdoc]

Or, depending on the percentage of steel in the Bolt, it may be possible to "spot harden" the Sear Engagement Surface.

 

[Mackjack]

Just only do mag dumps. Gives the sear and engagement surfaces an easy life

 

[KickStand]

Mine was similar initially but oddly enough it seems to have stabilized. I filed off the burr/edge. Doesn’t seem to be peening the same as it did when new.

Logically thinking there is a lot of distance that sear notch can be moved backward from wear and still not affect picking up another round.

I accidentally dropped my bolt from a low height and the corner was dented quite easily. Steel wouldn’t have had a mark so it got me worried if the machined firing pin will wear down quickly hitting all those primers. I’d say I have 3k+ round through this bolt and the fired primers still look the same (that I can remember) as when the bolt was new. Should the day ever come when the firing pin is too worn I’m sure a steel firing pin can be drilled from the back and pinned in place.

So in a nutshell the alloy is unique and can give reasons to worry but in real world use it should last countless tens of thousands of rounds before any gunsmith repairs are needed.

I also wondered about the firing pin in the A bolt. I think, I actually spoke to Vegas about it. I recall TheColtCollector was testing the life of the built in firing pin. I’m fairly certain his A bolt had tens of thousands rounds through it with NO problems.

With your bolt, I’d just hit it with a file. When/If it got too bad, I’d have it milled and have a small piece of hard steel put into replace the lost material. I’d have it brought back to factory dimensions with the addition of the steel and the milling.



I don’t think you’ve got anything to worry about for a LONG time. Just do more mag dumps in the meantime and enjoy it.

 

[Hey...]

In regards to the pictures… you can lessen the edge battering with firm ON or OFF of the trigger.

The slow partial trigger pull allows the sear to ride halfway and catch towards the edge causing the peening you see.

Let the sear ride full open or off.

Not mentally easy when you consider the lifetime of rifle/pistol trigger control… to now treat the M11 trigger as a baseball being thrown.

 

[Gaujo]

Just only do mag dumps. Gives the sear and engagement surfaces an easy life

10/10

Agree on jabbing the trigger.

 

[rybread]

Just only do mag dumps. Gives the sear and engagement surfaces an easy life

Problem solved. I love mine and think of Tom and tell people about him every time I shoot it. I’m not concerned about wear, I’ll keep blasting until it refuses to run.