Gunsmithing Surgeon 591/R Firing Pin Spring Question

[hk dave]

Hey folks. I've never taken apart a bolt action bolt and spring assembly so was wondering, is it possible for the spring itself to be installed backwards?

In other words... are Surgeon springs progressive?

I have a Surgeon action and i get a 5% failure to fire.

I had the Timney trigger redone by Timney. I've tried different primers. I've taken the spring/pin assembly out and check to see if the inside of the bolt was dirty or caked.

Timney can't duplicate my problem with their Surgeon actions.

Surgeon says I'm wasting my time and need to get a Jewell trigger.

Any ideas?

Thanks!

 

[hk dave]

Here is an image. Does this look correct to you guys?

The top is the Surgeon, the bottom is a regular old Rem 700.

After taking it apart, the spring is obviously not progressive, so that's probably not the issue causing FTFs. :/

 

[Aeon1]

How much pin fall (difference between the cocked and fired position of pin) is there with the Surgeon and the Timney trigger? I can't speak for a Surgeon directly but Remington's and Remington clones generally need from .240" to .280" pin fall for consistent ignition. If less than .240" that may be a problem. Have you checked spring weight? Easy to do with a block of wood and a bathroom scale.

 

[hk dave]

Pin fall on the Surgeon is .199... I measured it on my Rem 700 and it is .233.

Protrusion on the Surgeon is .060 while on my Rem 700 I got .054.

Surgeon claims they use a 32lb spring.

 

[RobertB]

My Surgeon stoped firing a while back, with loaded round the spring sounds REAL weak. I'm thinking that I need to send in for a rebarrel too. I've taken bolt apart and cleaned it. Everything looks fine. I'm stumped.

 

[Aeon1]

.199" fall sounds short to me for a Remington clone and a 32lb spring sounds high. Maybe they are using a short fall and a heavy spring to make up for it. If this is what they are doing you should check the spring weight. Have you asked Surgeon what the pin fall should be? If the pin fall is shorter than the what Surgeon says it should be it very well could be the trigger but also may not be. Why did Surgeon say to get rid of the Timney and why would the Jewell cure it?

 

[hk dave]

Andy at AD Arms has been PMing me and going out of his way to help me figure this out. Really great guy!

I took the measurements and a photo and sent them over to Surgeon.

They now feel I may have a bad cocking mechanism and want me to send the bolt in.

I really hope this fixes the problem because I'd really not like to switch over to a Jewell trigger.

I really appreciate all your help folks, you are the best.

 

[Aeon1]

What was the final result if any?