recoil lug height question

[hoagiejoe]

I was in the market for a stock and on the fence on whether to go with the version with an aluminum bedding block. I went for it but wish I had bought the standard version and bedded it. With that out of the way...

One small issue is the recoil lug pocket is not deep enough, so I plan to grind the lug. The bore in my recoil lug is .1 higher than where the action would rest (see attached, though this is not the lug I will use, it is similar in height).

Do I want the action completely resting on the block? If so, shall I grind it so the bore is maybe a couple of thousandths below the bedding block?

Thank You

Joe

[LynnJr]

The bore sits on the barrel tenon not the outside of the action.
Don't grind anything until you put the lug on the barrel and screw it all together and check the fit.

[hoagiejoe]

The bore sits on the barrel tenon not the outside of the action.
Don't grind anything until you put the lug on the barrel and screw it all together and check the fit.

Thanks. I used that lug as a reference, perhaps not the best idea. The lug on the barreled action rests against the bottom of the lug recess and the front of the action remains elevated well above the bedding block.

Perhaps a better way for me to look at this is to screw the action into the block with no barrel, then slide in the recoil lug, get the height difference and subtract the difference in OD between the tenon and barrel

[LynnJr]

Your going to need a little bit of room for the bedding material.
How much is the lug you are going to use lifting the action up?
And you can hog out the area under the lug if need be.

[MongooseV8]

I think you are fine. It looks like the lug is actually lower than where it will need to sit in the stock. That hole is for the barrel tennon which is a smaller diameter than the total diameter of the actual receiver.

Also if you have to grind something, I would leave the lug alone unless you have a mill. Those lugs are precion ground and it would be easy to warp one at home with a bench grinder due to the heat. Dremel out the lug pocket instead.

[ar15barrels]

I was in the market for a stock and on the fence on whether to go with the version with an aluminum bedding block. I went for it but wish I had bought the standard version and bedded it. With that out of the way...

One small issue is the recoil lug pocket is not deep enough, so I plan to grind the lug. The bore in my recoil lug is .1 higher than where the action would rest (see attached, though this is not the lug I will use, it is similar in height).

Do I want the action completely resting on the block? If so, shall I grind it so the bore is maybe a couple of thousandths below the bedding block?

Thank You

Joe

You are doing it wrong.
Install the lug on the action with the barrel.
You want to make sure that the lug is NOT touching the bottom of the lug pocket.
Put some clay in the pocket.
Install the barreled action and tighten to normal torque you use.
Remove the barreled action and check the thickness of the clay.
That thickness will be your clearance.
If the clay smashed down to less than 0.010" thick, I would shorten the lug.

[ar15barrels]

Your going to need a little bit of room for the bedding material.
How much is the lug you are going to use lifting the action up?
And you can hog out the area under the lug if need be.

Some of those aluminum bedding blocks are not very thick under the lug pocket.
I have broken through when milling them deeper.
I now shorten lugs instead.

The tapered side lugs are the most offensive, often being up to 1/8" longer than standard lug.
That's fine in a composite stock where you can just deepen the pocket, but troublesome in an aluminum chassis or bedding block.

[hoagiejoe]

update

Gentlemen,

Thank you for the replies. I'm happy (albeit a bit embarrassed) to report I found a lug that is significantly shorter. I recently moved and not completely settled nor organized (that's my excuse anyway).

The shorter one seems to be short enough; the action rests completely against the bedding block. However, I will try the clay method to gauge how much clearance I have. I do not have the proper tools to grind precisely but fortunately have a machinist nephew with access to the right equipment. If I do need to take it down, I'll ask him to help me out.

Thanks again,

Joe

[kendog4570]

... fortunately have a machinist nephew with access to the right equipment. If I do need to take it down, I'll ask him to help me out.

When shortening the barrel bracket, mount a 0 MOA scope base to the receiver and use that flat as a reference to mill the lug bottom square to your barreled action.