True & Time

[tenwalker]

When they True & Time an action do they do any work on the trigger?

[GaCop]

I don't believe any trigger work is involved with T&T.

[82boy]

Nope, but the timming is related to the trigger used. So if you have an action timmed with one trigger, and switch to another it will change the timming.

[Ray Gunter]

... action timmed with one trigger, and switch to another it will change the timming.


Explain this please.... I dont get it

[82boy]

... action timmed with one trigger, and switch to another it will change the timming.


Explain this please.... I dont get it


Don't feel bad, most gunsmiths don't either, this is why Sharp Shooters Supply is one of the slight few that do this line of work. You should ask Fred at SSS he can break it down to exactly why with numbers to back it up. Timing deals with the relationship of the sear and the cocking piece, the trigger is directly involved with this relationship, all three function in harmony, you change one you affect the other two.

[Axtell3]

Good answer!

[yorketransport]

I just copied this from the FAQ section at the top of this forum.

The following is Fred's own description of the Truing & Timing service he offers for Savage actions.

Truing and Timing the Savage Action

When I build a rifle, truing and timing the action is a standard procedure. Most shooters understand the concept of truing, but are confused about what "timing" is. When an action is out of time, it is typical that the bolt operation is stiff, bolting or unbolting. This is caused by several things, such as the cocking ratio being out of balance, and the sear engaging too early or too late. Another geometry problem is that the lead-in ramps and the primary extraction are not synchronized, but are actually in conflict with one another. When we true an action, it consists of much more than just machining a few mating surfaces. First the lead-in angles (the ramps that lead into the lug seats) are re-cut to a true helical cam. The factory cuts are made with an end-mill, and are not helical. A helical cam is like a spiral staircase, and I have developed special tooling to precisely cut the lead-in angles to engage the whole width of the bolt lugs. The receiver face and the lug seats are machined to square them up relative to the receiver threads, not to the bore of the receiver like most gunsmiths would do using conventional wisdom. The reason for this is the barrel will be square to the bolt face. Concentricity behind the bolt head is not critical, as the "float" in the bolt head will allow the bolt body to be off center as much as .045" in any direction, and still get full lug contact, although I've never seen one that bad.

The bolt head is squared, front and back and the firing pin protrusion is reset to .040" +- .005". After this is done, the firing pin travel is corrected and timed with the sear and trigger. At this time the cocking ratio is corrected to avoid over cocking and hard bolt lift. The cocking ramps are reground to the correct angle, and lastly the barrel nut is faced for 100% contact.

[Dirk]

... action timmed with one trigger, and switch to another it will change the timming.


Explain this please.... I dont get it


I think Ray doesn't know what "timming" is. As a matter of fact, neither do I! I know what "timing" is, but never heard of "timming" an action before.

[Blue Avenger]

http://img.photobucket.com/albums/v675/gcidso123/emocons/fing20.gif ;D ;D

[Ray Gunter]

... action timmed with one trigger, and switch to another it will change the timming.


Explain this please.... I dont get it


Sorry guys I've been out of touch for a few days.... back now.
Oh, as for "timming" or "timing" dont nun matter to me, cause its a shallow mind that can only think of one way to spell a word.

Back to the subject.....I don't believe I fully explained my issue. Please allow me to try again.



... action timmed with one trigger

This is true and I understand and I believe. A trigger with a sear must be in place to get it correct.



... , and switch to another it will change the timming.

Here is where I fall off. The positional relationship of one triggers sear as to that of another I do not believe will amount to enough variation to be sufficient as to justify or require a re-timing.

Now with 30+ years as a mechanical design engineer this is just my opinion.

[82boy]

Ray, does a SSS competition trigger engage the sear the same way as a factory trigger? Does a SSS evolution? Does a Rifle basix sav 1, or sav II? Would different tolerances in triggers and sears change the timing?

When I switched from a SSS Comp trigger to the Evolution there was a difference, and the action had to be re-timed. Fred had to rebuild (Make it taller) the sear flag where it contact the cocking pin when they was changed out.

[sharpshooter]

The sears are a stamped part, and have a lot of variation. Other factors come into play besides the sear, and not 2 are alike. This hold true on other makes as well. Even on custom actions there is usually a variation on trigger hangers just for this purpose.

[Ray Gunter]

Not having analyzed the geometry of various trigger sears and their positional variations imposed by the respective hangers. I must bow to those with real applied experience. Thanks Fred

But hey we learned something new today. And had a stimulating conversation getting there. Thanks for all who contributed.