Home Forums Hunting & Shooting Gunsmithing Lug lapping question

Howa 1500 could use a little lapping to even out the wear. (1 lug is 80-90%, the other lug about 20%)

Have a few questions:
- I have some loctite Clover 280 grit lapping compound already, is it suitable for starting out?
- after putting a small dab of compound on the rear of the lug with the most wear, do I just move the bolt up and down while trying to pull-back on the bolt handle enough to insure the rear of the lugs are in contact with their recesses?

Any other watch outs you would suggest?

Thanks for any tips you can provide.

Cheers!

In a nut shell;
This is generally considered inadvisable on an assembled rifle, just because it’s so difficult to then remove every trace of abrasive. Should be done on a bare action with the barrel removed so when finished every trace of compound can be cleaned away to prevent ruining everything as time goes on. A tool (wooden dowel to shaped fit the bolt face) is usually used to put pressure on the bolt face while lapping. Another reason for de-barreling is that the head space, which may be overly increased with the lap job, can then be adjusted.
There are good articles out there but done right, it isn’t quick or easy & done wrong, it IS a quick & easy way to completely ruin a decent rifle.


“In a nutshell! You couldn’t put in a barrel without a bottom!”

Well another view might be, 280 Clover will cut just fine start to finish.Thin it a little so it will flow into where you need it when you push the bolt forward out of contact. Pull the striker spring and firing pin out of the bolt, insert bore rod/dowel rod, ensure tip of rod will not damage bolt face, coat the lugs, muzzle down apply significant force, lap, re charge, lap, re charge, ad nauseum, clean, prussian blue check...on and on, don't go for anything even approaching 90% contact...just get it somewhat even. In the event the lugs or receiver abutment have a surface or skin hardening, you don't want to get thru that. Lapping by it's proper definition, does not get aggressive enough to change headspace.

If you are worried about headspace after lapping your lugs, you need a lot more than lapping to fix what ails that action.... and it won't be a home fix unless you have a good lathe and know how to use it...

I'd be willing to bet a steak dinner that the lug that has 20% contact is the top lug when the bolt is in battery. There is a reason the top lug doesn't contact fully. The cocking piece and trigger sear force the rear of the bolt upward when in battery. It will be enough in most actions to unseat the top lug or cause it to have very little contact. The bolt to action raceway clearance allows for the bolt to move up in the rear and cause the misalignment. If that is the issue you are dealing with, lapping the lugs will assure you of one thing. That is that the bolt face will then be out of square with the chamber/bore of the barrel. Also you may have the afore mentioned headspace issues as well. The only way to correct the bolt slop that causes all this is to sleeve the bolt then lap the lugs into contact. Without sleeving the bolt you will do more harm than good.

This is certainly the case with the Remington 700 or the Pre-MOA trigger Model 70. With the Howa, the contact between the sear and cocking piece is vertical so it doesn't have the tendency to lift like the Remington or earlier Winchesters. It is still a possibility though. GD

Thanks very much for the great comments/advice and the education.
I learned a lot.
This is not something I am going to try myself, as there is too much probability of me screwing-things-up!!

Will contact a local gunsmith who is willing to take a look at it and determine if anything even needs to be done.

Cheers.

Also, think about the bolt body to receiver clearance when you do this. And what happens after you do it.

Good shootin'. -Al

Smart!

I hope I never buy a “used rifle” from any of the guys who think it’s easy.

How does it shoot in it's current state? If there are no accuracy issues, what do you hope to accomplish? .....other than peace of mind.

Yes sir!

I think for the shade tree gun butcher the term lapping should be scrapped as a gun ruining disaster waiting to happen. I have no problem with polishing the lugs slightly for smoother operation if not accuracy. I was scraping up other parts of the bolt so I wrapped it with pipe tape to the point it created a bushing. This and a light touch for a minor polish are not likely to create head space issues. As others noted good to take off: extractors, firing pin and trigger and the barrel too if you really want to go after it. As far as accuracy goes squaring the front of the receiver is far more critical than lug contact in my experience.

Flush and scrub out everything multiple times afterward.