bolt face

K

kasjaka

Guest
would a tool made from 4130 pre heat treat be hard enough to lap a boltface
without additional heattreat
thanks
scott
 
Lapping Bolt Face?????

Why would you want to lap a bolt face?? Certainly not to true it, as the lap will just follow the existing surface.

Maybe this is something I have not heard of........jackie
 
Laps are usually made of a soft material, like brass or lead, that will permit the abrasive to be held in the soft metal while cutting the harder metal.
I think someone (Brownells?) makes such a tool. The tool is used when one has a bolt, like a Rem 700, that has the boltface on a slight angle or is not flat, maybe dipped or high in the middle.
You need to hold the bolt accurately, in the vertical mode in a vertical mill while bringing the spinning lap into contact with the boltface.

There was an article in American Rifleman (or maybe Rifle Magazine) about 30 years on the subject of bolt faces that were not perpendicular to the bolt body. It suggested that a non-perp. bolt face was the cause of the situation where a fired case is difficult to close the bolt on when put in the chamber. If the case with the "crooked" case head is placed 180º from the original position, you double the amount of interference.
I do not think that this is a concern on any of the custom actions offered today.

Jay, Idaho
 
lap

was just thinking it may be a good idea to try
am building a 40x rimfire and thought it might be something to consider
true receiver face lap locking lugs true threads seems like lapping bolt face couldnt hurt
any suggestions or am i wasting time and effort
thanks
scott:confused:
 
Harold Vaughn'S RIFLE ACCURACY FACTS PAGE 51 - 52 indicate several things about bolt lapping. Perhaps your local library would have a copy.

Don
 
kasjaka said:
was just thinking it may be a good idea to try
am building a 40x rimfire and thought it might be something to consider
true receiver face lap locking lugs true threads seems like lapping bolt face couldnt hurt
any suggestions or am i wasting time and effort
thanks
scott:confused:
Click to expand...

If you true the action face and the threads and the lug recesses in one set up... you don't need to lap the locking lugs, they should also be machined. Lapping really isn't the way to "true" the surfaces. I only very lightly lap after machining just to confirm the fit is good. I think as far as the bolt face is concerned in a rim fire - how far off can it be? And does it really matter with factory ammo compared to reloads in a center fire? Machining is still better than lapping.
 
Do what Dennis says. Just remember that the sear may push the rear end of the bolt up which will give you a false reading on the locking lugs and make the bolt face canted a bit. The Savage type bolt is the answer for near 100% lug engagement. A while ago with the help of Idaho Jay and Marlee Parks, I did a Savage bolt conversion on a Rem 700. It was a real excersise and before I would do it again I would just buy a bolt from the guy in White City. The only thing is with the Savage bolt conversion there is no need to true the lugs.

Don
 
Gunner223 said:
Jay, According to Harold Vaughn is never has been much of a concern, even on a sporter rifle.

Don
Click to expand...

I was not endorsing the bolt face lapping procedure, just offering what I thought the reason was and a source/technique for doing it.
It would have been great to have been able to read Vaugn's second book but he was taken from us before it was completed.
If his book is still available from PS Publishing, buy it, you will not be sorry.

Jay, Idaho
 
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