How important is blueprinting an action

[tony d willIiams]

Absolutely !!!

I do everything in a specific order and the first thing is to establish a bench mark surface that everything is based off of,

Everyone has the order that they like to use and I have mine. It is probably like most. What is the saying? "Measure twice (In my case being anal, it may be 3 or 4 times to be sure) and cut once"

J E CUSTOM

J E Custom,

Ha, I like anal. My wife used to tell me, and others that I am extemely anal. Then I made some equipment for our handicapped son. She now tells me that I am precise and try hard not to make mistakes.
And yes, I do measure more than twice and work through my blueprints to set the proper order of things.

 

[LRSickle]

Absolutely !!!

I do everything in a specific order and the first thing is to establish a bench mark surface that everything is based off of,

J E CUSTOM

If you have time, I would love to hear what your specific order is.
I measure receiver at critical points, true the bolt lug abutments [if needed], check bolt lug bearing surfaces, chase receiver threads if needed [nearly always], lightly face receiver until all indication of previous tooling is gone, thread and face barrel tenon, cut bolt recess [if needed] and then chamber. Can you add or correct anything for me.

 

[Mram10us]

I would love to see a list, mainly the order in which you blueprint an action. Looking at you Wheeler, JE and Shortgrass. Also, anyone else I don't know that has a good flowchart

perfect timing LRSickle Glad I'm not the only one asking

 

[Alex Wheeler]

Very few actions are designed to have the trigger timed without major rework. Properly timing an action should not result in reduce firing pin fall.

 

[John Porter]

I am very lucky to have the most honest no nonsense Gunsmith, and he has done a lot of of re-barrelling for me over the years. He only dose "Trueing " when he thinks it will help. He could make money for nothing by doing it and I wouldn't have questioned him. He never has in all nine cases, and my rifles are all shooting 0.25 MOA or better. Actions included Weatherby Vanguard, six Howa an old B.S.A and a Savage 116. One of the Howa's is a mini-action 762x39 Converted to 6mmPPC, [the most fun I have had in years] and he said it was one of the best actions he had ever worked on.
High praise from someone who spends his days fitting Surgeons, Defiance, Stiller and Accuracy International actions.

 

[J E Custom]

If you have time, I would love to hear what your specific order is.
I measure receiver at critical points, true the bolt lug abutments [if needed], check bolt lug bearing surfaces, chase receiver threads if needed [nearly always], lightly face receiver until all indication of previous tooling is gone, thread and face barrel tenon, cut bolt recess [if needed] and then chamber. Can you add or correct anything for me.

I don't consider myself as knowledgeable as many of the smiths like shortgrass and Ed so I approach everything from the most logical starting point for me. It is probably a different sequence that some but it works for me.

I base everything off the bore centerline because when I chamber and thread this is the benchmark/reference that everything is based on. with that said, First I have to establish the bolt centerline to do all of the machining off of because I want it to perfectly line up with the bore centerline.

After establishing the true bolt centerline in the action, (With no runout) I can begin machining everything that needs truing. I start with the action face, because it gives me a good point to measure from for abutment height differences and corrections. I can also establish if there is any runout in the receiver threads and true them before the barrel threads are cut to get a better fit.
After all machining on the action is done I can machine/true the bolt lugs, and face the bolt face true and flat, then lap/polish the lug surface for finish if necessary for ease of bolt lift and operation. At this time any hand work needed on the action can be performed.

With the receiver as true as I can get it in all areas (Except the OD which is rarely true and doesn't effect the alignment to the bore) I don't turn the OD unless the owner wants me to because of the re finish requirements. I can set up the barrel to begin chamber work. All barrels are turned between centers to identify any runout before starting any work. (As one sage gunsmith always says, "You cant make a silk purse out of a sows ear") and if it is beyond what I think is acceptable I will replace it. If it checks out that the bore is straight and it is centered using the bore on both ends the chamber work can begin.

At this point there are many different ways to start the process of shouldering, threading, recessing the bolt for the action requirements chambering and head spacing so This may vary from smith to smith. The main thing that I never do is to take the barrel out of the lathe until all machining and fitting is done. It is very hard to guaranty the same set up every time, so I have everything done to the action and all makeups are finished before the barrel comes out of the lathe to be turned around for crowning and or threading for a muzzle brake.

There are so many details to doing each step that I skimmed over them to keep this from becoming a book, but it think I listed the different processes in order best I could and hope it is clear why this is the way I do it and. If I missed something it is just my writing skills aren't very good.

J E CUSTOM

 

[GunHawk]

Thanks to JE and Mram10 for your input; it really filled some gaps in my knowledge and understanding.
My next question to all you experienced smiths is: Is there one ore more factory actions that are generally better made so that they usually require little or no work compared to other actions? I expect that many smiths will have preferred actions based on familiarity or "easy-to-work-on", or some other parameters. I happen to prefer 3-lug actions because they make more sense to me, for the same reason a 3 legged stool makes more sense than a 2 legged one, but that is not what I'm asking. What factory actions generally require less work?

 

[J E Custom]

Thanks to JE and Mram10 for your input; it really filled some gaps in my knowledge and understanding.
My next question to all you experienced smiths is: Is there one ore more factory actions that are generally better made so that they usually require little or no work compared to other actions? I expect that many smiths will have preferred actions based on familiarity or "easy-to-work-on", or some other parameters. I happen to prefer 3-lug actions because they make more sense to me, for the same reason a 3 legged stool makes more sense than a 2 legged one, but that is not what I'm asking. What factory actions generally require less work?

I find that most brands are about the same on average. If I had to choose one factory action that typically had fewer problems, It would be the Weatherby Mark 5.

There are a few that are typically worse than most and fortunately most people don't choose it to build on.

On the most popular action (Remington 700) there seems to be a wide difference from one to the other. Some of them are very close and others are quite a bit out of the desired tolerances and must be dealt with for and accuracy rifle use. the one thing I will stick my neck out and say about them is that they respond well to good blueprinting and bedding. (I think this is one of the reasons that so many custom actions are cloned after the 700 design.

Just my opinion

J E CUSTOM

 

[Rick Richard]

If I am going to spend my money on a custom barrel and the smith cost, then you bet I am going to do everything I can to ensure the most potential for accuracy. Like mentioned, factory actions are more than likely need to be trued.

 

[nksmfamjp]

What is the general impression of Win 70 classic actions say 1990-today? Good? Generally need lot of truing?

 

[IdahoCTD]

Thanks to JE and Mram10 for your input; it really filled some gaps in my knowledge and understanding.
My next question to all you experienced smiths is: Is there one ore more factory actions that are generally better made so that they usually require little or no work compared to other actions? I expect that many smiths will have preferred actions based on familiarity or "easy-to-work-on", or some other parameters. I happen to prefer 3-lug actions because they make more sense to me, for the same reason a 3 legged stool makes more sense than a 2 legged one, but that is not what I'm asking. What factory actions generally require less work?

Tikka actions tend to be quite good. Most of the others are off at least .001in every dimension.

 

[Mram10us]

I just tore into my first tc compass and really like the action. I don't have my jigs made up to true them up yet, but will let you know how close to square they are. I agree that tikka are pretty tight

 

[GunHawk]

Tikka actions tend to be quite good. Most of the others are off at least .001in every dimension.

What about SAKO?

 

[Carryacolt]

I use this word all the time in reference to accuracy. "Consistency" The more accurate everything fits the more consistent/repeatable it will be.

The object of blueprinting/truing it to keep stress and movement to a very minimum and locate the cartridge in exactly the same place in the chamber every time and also control movement during firing. If all parts of an action are aligned with the bore centerline, Thrust is in a straight line opposite the bullet travel minimizing the thrust vectors that could effect accuracy in the rifle. With the bolt aligned with the centerline and with proper head space the cartridge is located in the same place in the chamber and not allowed to move in any other direction that could launch a projectile with yaw or improper alignment.

If we go to great lengths to load perfect (Concentric ammo, it doesn't make sense to allow your equipment to alter this alignment. Doing many concentricity test, the concentricity of the ammo makes a huge difference in the accuracy. Best accuracy is with 0.000 concentric ammo as you add eccentricity by 0.001 accuracy falls off, when it reaches 0.003 accuracy is not acceptable to many.
and by the time you reach 0.006 it is practically unusable. it will still fire but that is about the only thing it does.

So back to the question If the action has more than 0.0005 misalignment in certain areas it will not be as accurate as it could be. Many shooters will not be able or capable of seeing this improvement, but even the best shot cant reach his potential in a poorly assembled rifle.

Slack or improper alignment Is not conducive to consistency, so it should be minimized. One of the quickest ways to spot poor workmanship, is to try a fired case in an action/chamber for ease of closing. Many times it will have to be index't in the same position it was fired in to freely chamber because something was misaligned or allowed to move.

J E CUSTOM

You stated: "Slack or improper alignment Is not conducive to consistency, so it should be minimized. One of the quickest ways to spot poor workmanship, is to try a fired case in an action/chamber for ease of closing. Many times it will have to be index't in the same position it was fired in to freely chamber because something was misaligned or allowed to move."

This is the problem I'm having right now with my M-70. When I place a fired case into the chamber using the bolt (with the firing pin assembly removed), it closes hard. If I rotate the brass in 15 degree segments, it will come to a spot where it closes much easier.
Just where is the misalignment occurring?
I figure the barrel is not aligned true to the action. The bolt face....probably is not perpendicular to the bore either. The lugs are fairy close as I "very cautiously" lapped them.
Just haven't decided if it's worth the time,effort, or money, to get it all aligned.
This is a factory hunting rifle.
At least I know now what the problem is and I can stop driving myself nuts.