Action Truing Jig Help

[Shooting in the wind...]

Hey fellas,
I need some help with my truing jig I am in the process of machining. My problem is, is that I have no idea of the locations for the 4 holes in the front of the jig and the 8 holes in the back for doing REM 700 long and short actions. Could somebody please help me or point me in the right direction? Any reliable dimensions would be greatly appreciated as I only have one piece of material, so I need to get it right the first time. Thanks again guys...

 

[Cigarcop]

Here’s what I made...... I didn’t want any pressure on the back of the action....... I also didn’t come up with this idea just copied it.

 

[boltfluter]

I have one just like Keith's and it is the cat's meow!

Paul

 

[GenePoole]

I did mine from the measurements of Pastor's Viper fixture: 2 inches apart starting 0.5 inches from the end.

 

[butchlambert]

Just take measurements from both a LA and SA.

 

[Shooting in the wind...]

My material is only about 4 inches long. I don’t particularly care for how far the Viper holds the action away from the chuck, even though I’m sure it doesn’t matter with a solid setup. Any way I can still use the one I made?

 

[Shooting in the wind...]

This is what I have so far, it will be closer 4.250 to 4.5.

 

[Dusty Stevens]

How big is that hole? I wouldnt go very far over biggest action od.

 

[Shooting in the wind...]

The ID is 2 3/8”. It was the only material I could source locally. The OD is slightly under 3.5”

 

[GenePoole]

My material is only about 4 inches long. I don’t particularly care for how far the Viper holds the action away from the chuck, even though I’m sure it doesn’t matter with a solid setup. Any way I can still use the one I made?

I didn't care for it much either for the same reason. That's why I made my own that threads directly to the spindle. Super solid. I also prefer steel where possible, and I used 1/2-20 v. 1/2-13 adjustment screws to give finer control.

 

[Rebar]

I found this drawing online. It might give you an idea on the set screw spacing. I made my truing jig like the one cigarcop posted. I have an extra one I made. If your interested in it send me a pm.

 

[Alex Wheeler]

Make one like cigarcop's. You do not want any influence on the back end of the action. Its very easy to flex an action. Truing an action is a finesse operation. Its actually one of the tougher jobs to do right. I have a few jigs, some are quite large for actions with integral rails, but they all only grip the front half of the action. You also want to use a full diameter ground rod, not one with bushings. The tighter the bolt fit the more critical the setup becomes. After you true the action, apply pressure to the bolt face and see if the back end of the bolt is being held against the top or bottom of the action, or if its free floating in the center...

 

[efoleyjr]

Make one like cigarcop's. You do not want any influence on the back end of the action. Its very easy to flex an action. Truing an action is a finesse operation. Its actually one of the tougher jobs to do right. I have a few jigs, some are quite large for actions with integral rails, but they all only grip the front half of the action. You also want to use a full diameter ground rod, not one with bushings. The tighter the bolt fit the more critical the setup becomes. After you true the action, apply pressure to the bolt face and see if the back end of the bolt is being held against the top or bottom of the action, or if its free floating in the center...

Alex,
Are you saying that the rear of the bolt should be fitted and be a snug fit or it should move freely and be centered?

Ed

 

[Alex Wheeler]

Im talking about an action thats actually square. With the lugs seated the rear of the bolt can move in all directions because its free floating. If its held in one direction, its not square.

 

[efoleyjr]

Alex,
I made a collar for the rear of my R700 and fit it to the action so there is no slop at the rear when bolt is closed.Both lugs and abatements for full contact at battery. Is that wrong?See pic's that are attached. Thanks
Ed

 

[tobnpr]

If your spindle is large enough to handle the action, another way to skin the cat is with a snug collar like the LaBounty over the front of the receiver.
Properly fit mandrel in the raceway, put it between centers. True the collar making it concentric to the raceway. Chuck up/dial in the collar in a 4-jaw or Set-Tru. Can't be anything but right.

 

[Shooting in the wind...]

If your spindle is large enough to handle the action, another way to skin the cat is with a snug collar like the LaBounty over the front of the receiver.
Properly fit mandrel in the raceway, put it between centers. True the collar making it concentric to the raceway. Chuck up/dial in the collar in a 4-jaw or Set-Tru. Can't be anything but right.

Do you have a pic of what you speak of???

 

[Alex Wheeler]

Alex,
I made a collar for the rear of my R700 and fit it to the action so there is no slop at the rear when bolt is closed.Both lugs and abatements for full contact at battery. Is that wrong?See pic's that are attached. Thanks
Ed

No thats fine.

 

[Alex Wheeler]

If your spindle is large enough to handle the action, another way to skin the cat is with a snug collar like the LaBounty over the front of the receiver.
Properly fit mandrel in the raceway, put it between centers. True the collar making it concentric to the raceway. Chuck up/dial in the collar in a 4-jaw or Set-Tru. Can't be anything but right.

So long a your jaws are ground dead nuts straight to the spindle bore. I would definitely throw an indicator along the mandrel again after you dial in the collar to be sure.

 

[Shawnba67]

I bought the Greg Tannel action truing dvd he mentioned how little in/lb of torque it took to tweak an action in fixture. My fixture holds front ring and rear of action I had reamed the action to .710 and was indicating off the mandrel 65in/lbs would cause noticeable tension on the mandrel. That worked up to using 3 fingers on a box end wrench and only finger turning no using your wrist! Heck a lot of scope bases are torqued higher than 65!(not to spec but bubba does what he does)