Gunsmithing Truing...lapping..?

[eboggs]

Hi guys,

Did another search, cant find anything specifically for what im asking, i apologize if there is...

I have a Savage and Sooner or later i may replace the barrel..(Dont really know how it shoots yet but the rifle was made in 1999)..

What is Truing and lapping a bolt...do?

Does it really need it? Does it improve accuracy? Smoothness in opperating? what? I dont understand.

Also, i know you can replace your own barrel on savages...but can you do it as precise as a gunsmith? or will this cause loss in accuracy?

thanks,

Ethan

 

[BOLTRIPPER]

Re: Truing...lapping..?

short story.......


if the gun shoots well...leave it alone and shoot it

lapping the lugs would require removal of the barrel and doing a mechanical masturbation with lapping compound on both the front and rear of the lug faces to assure plumb contact....

but tis nothing for the novice as one may not really need it.

truing an action is another process that requires a lathe and the knowledge...and jigs and tooling ..

but....have a reason to do this !!!

 

[eboggs]

Re: Truing...lapping..?

No worries wasnt gonna try and do any of this myself...

JW if i decided to get a new barrel, if this would be wise to get done as the barrel would be already off.

Thanks for the info.

Ethan

 

[sobrbiker883]

Re: Truing...lapping..?

Lapping the bolt on a Savage is uneccessary as they have a floating bolt head.
Truing up the reciever face may be considered, if you aren't changing the barrel yourself, have your smith check if it needs it while he has the bolt off.
I've found that one of the best things to do is to get a nice and true surface ground recoil lug and drop that on when you change barrels.

Back to what MrRipper said:
<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: BOLTRIPPER</div><div class="ubbcode-body">
if the gun shoots well...leave it alone and shoot it
</div></div>

 

[DMann]

Re: Truing...lapping..?

Truing and lapping of bolt lugs ensures that the lugs are in 100% contact with the action recesses/abutments, when the bolt is in battery and at the moment of ignition. Supposedly, this means that the bolt doesn't move any due to uneven contact with the action, so no negative vibrations or movements are imparted to the rest of the rifle as the bullet rumbles down the barrel bore.

One reason Savages tend to be more accurate out of the box is the "floating" bolt head that "self-seats" when in battery, so that the absolute need for truing or lapping isn't as critical as with a system such as a Remington that has a one-piece bolt body.

BUT - getting everything as true and square as it can be is never a bad thing. If you do true/lap a Savage, you simply remove a little more stress from the system. It may be so infinitesimally small as to be virtually unnoticeable, but it couldn't hurt.

If you are going to rebarrel anyway, it certainly wouldn't be unwise to have the action gone over.

 

[sobrbiker883]

Re: Truing...lapping..?

Very good point Doug, I'm sure truing of the mating surfaces would help even in the floating bolt design.

While we're talking Savage work, if you are at the point of having a 'smith working on the pieces, while they are in his hands have him time the bolt, as Savages tend to have poor timing out of the box.

 

[DMann]

Re: Truing...lapping..?

What he said - timing the Savage bolt is a good thing and requires a recut of the camming surfaces. Gives smoother bolt lift and improved primary extraction.