Truing an action- what difference does it erally make?

If you were to take a standard factory action, and shoot it out of the box, then true it up- what would the actual accuracy difference be?

The obvious answer is "it depends". Every action is different, each one will be a little more or less true, machined a little better or worse.

So if you were to take 100 actions, leave them bone stock, shoot them out of the same theoretical barrel, then take 100 trued actions and repeat- what would the average improvement in accuracy be?

You could poke a million holes in this question but hopefully the main point is getting through.

Thoughts?

This has been discussed a million times...

My 7mag shot half moa, then I sent it to sss for a work over. When I got it back I spun on a CBI 284 barrel and it shoots under a half moa. But the action is smooth as silk and can be operated with a single finger from the prone position. Worth every penny to me. Did it help accuracy? Don't really think so, but id do it again just for the smoothness of the action.

To add a twist to your thoughts would be to use a factory barrel and then a custom . Good question you present.

OOOOOOOOOOOOOps i'm thinking barrel with shoulder not nut . Sorry

Good replies, thanks. I left timing out of the equation because I don't care about "smoothness", just accuracy. The base question was in regards to the action as a sole component- excluding all other variables, what difference will trued vs untrued make?

Sorry to not be clear, don't mean to preclude it as a variable- but to isolate it as such.

Assuming for argument's sake that all other variables are the same, what difference will be seen between a trued and untrued action?

If we are doing this with all things equal on the Savage I feel confident in saying they will be equal.

Reason 1: Floating bolthead will compensate for slight difference.
Reason 2: I have already done it with 3 target actions. That is why I quit truing. Saved time and effort and since I do not compete any more it would not make but maybe a hair difference in group size. However I never saw any difference and I shot only quality barrels.

Neal

Thanks for the reply- especially the first hand experience.

So shooting trued PTAs vs stock ones you didn't see a noticeable difference in accuracy?

If you are building a top of the line precision target rifle and you want to squeeze out every milimeter of accuracy you can get, then having this kind of work done is a must to eliminate every possible varible you can. If its a hunting rifle that you punch paper with on occasion to keep in practice then you will probably never see any difference.

Many people think that a Savage is a remington , and they try to do the things that work in a remingtion action, the fact is a Savage is not a remington action, and the two differ as much as night and day. With that said lets consider a savage action for our discusion. Truing an action only makes things straight. Making things straight will affect how the bolt slides in the action, and how the scope bases fit, and that is it. This is what you get from most gunsmiths. Yes as mentioned the Savage floating bolt head design takes up the assoated problems with lug contact. The true magic is in timming, most benchrest shooters know this well, but it is sad most gunsmiths dont understand what it is. Proper timming ensures proper ignigtion. Eratic ignigtion can cause all types of problems, such as cold fires that cause unexplained shots, to rounds not going off, to inconsistant groups.


Now with that said, with truing the action you will not see any benifit with accuracy, you may feel the bolt move a bit more freely. Trimming is where accuracy is involved, and it is at the point where most shooters will not notice the diference. To start the gun out of box shoots better than most shooters can handel, but when a shooter gets to the point, that they are at the accuracy end point of that rifle, then timming is where the gain come is.

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Originally Posted by mattri

If you were to take a standard factory action, and shoot it out of the box, then true it up- what would the actual accuracy difference be?

The obvious answer is "it depends". Every action is different, each one will be a little more or less true, machined a little better or worse.

So if you were to take 100 actions, leave them bone stock, shoot them out of the same theoretical barrel, then take 100 trued actions and repeat- what would the average improvement in accuracy be?

You could poke a million holes in this question but hopefully the main point is getting through.

Thoughts?

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To me it seems you answered your own question... Not sure what are you wanting to hear, maybe you just want assurance that truing an action is not money wasted? I think that the only way you will be able to notice any real improvement is if savage really messed up the action.

I had a T&T from sss done to my action. The gun shot better than me before and now it still does. What I gained from it is the piece of mind that the action is at it best that It can be and if some day I learn to shoot straight the gun will not be holding me back... In other words, Truing (and timing for that matter) will not necessarily make your gun shoot BETTER but it will not make it shoot worst...

So to answer your question in a different way, Truing (and timing in my case) my action gave me the piece of mind that my action is at is best performance which in turn gives me a great deal of confidence every time I pull the trigger.

PS - I know you left the timing out of the discussion which is fine as it is a separate process. However I have to ask, have you had any action timed? My bolt is so easy to work now that it is a true joy. You can probably achieve a very easy to work bolt by doing the lift kit but your cocking ramp angles will not be in time and that can also add drag to the bolt.

COCKING TIMING= Relation between the cocking cam surface and the sear engagement to the cocking piece. There is Cock on Open Timing, and Cock on CLose timing. Two different defenitions for two different action types.

LOCK TIME= distance in time from the disengagement of the sear to the contact between the firing pin and primer.

Truing= To make an action Concentric meaning that there is a center line in your action, that is the firing pin hole in the bolt face, every part of the action and barrel joint are centered around that point.

These definitions are from Gunsmith Journals, Books and School, I'm not a word nazi but good Lord,

You folks aren't getting your actions timed, your having the cocking surfaces ground to a lesser angle to make cocking easier.

If you want to SPEED UP LOCKTIME, then clean out the bolt with parts cleaner, and reassemble dry. If you want it to slide smoother then polish the bolt body with buffing compound and debur the race ways.

Basically the Internet is filled with opinions, good and bad (including my humble BS opinion). If you really want to know some accuracy FACTS, buy some books my friends.

Harold Vaughan's "Accuracy Facts"
Maj Gen Julian Hatcher's "Hatchers Notebook"
James Howe " The Modern Gunsmith"
Dave Wolfe "Gunsmithing Tips & Projects"

Interesting replies all. Guess I should have been more clear from the start. I'm not looking to have an action timed and/or trued. The question was more for information's sake. It seems that most times when action work is done it is in conjunction with a number of other steps. For example, a person will take a stock action, have it timed and trued, or blueprinted, and at the same time add an aftermarket trigger, rebarrel and put it in a different stock. It would be interesting to isolate these steps and see how much of a difference each makes.

I especially appreciated the references to a psychological affect. I am as guilty as anyone of little reloading "tricks" that border on superstition, and competition is certainly a mental game as much as anything.

One thing I find curious is that in this and other threads when this question is asked cost keeps coming up. I guess when someone asks if there is a measurable difference in a trued or untrued action folks take that to mean "is it worth the money?". My question was really more academic than anything. It sounds like there hasn't been any definitive tests done on this. I wish I had the time and resources to make a comprehensive comparison, would love to see the actual data.

Anyway, an interesting subject, thanks again to all for the good information.

Like I said, buy some books Mattri

Go buy the book ACCURACY FACTS by harold vaughan, It is the one book that does away with these crazy superstitions. He was the chief engineer in Ballistics division for the military for the last 40 or so years, He did exactly what you are wanting. He made comprehensive experiments over the course of 10 years with rifle accuracy tests.

Cool thanks for the heads up.