bolt wearing on floor of upper receiver as it tilts

[hso]

I've got one of Meeper's 5.56 FALs on the aluminum receivers. The bolt is wearing on the floor of the receiver as the carrier travels to the rear. It happens just as the bolt tilts down.


HELP!!!


How do I stop this wear and save my super light weight little Al friend?

[gunnut1]

Pictures? Good old Williams.

[Deltaten]

A dab of Silicone/Teflon grease, mebbe?
Best cure for steel vs aluminum galling/wear that I know of.
HTH,
Paul

[hso]

http://thehighroad.org/attachment.php?attachmentid=41978&d=1152417382

The composite image shows the wear on the floor of the receiver. The hammer comes up though the receiver in this area and the bolt tilts in it's travel back. This tilt causes the lower rear of the bolt to dig into the floor of the receiver for about an inch.

How do I stop this and how do I fix this?

[gunnut1]

HSO the receiver is aluminium. It is not has hard a steel. There may not be a FIX for it. The bolt is going to drag. There is no way to stop that that I am aware of.

Is it gouging the metal or has it just worn the anodizing off? Someone suggested a grease and that MIGHT be the only answer other then a new receiver.

A close up would be better. Your composite is hard to see detail on.

[hso]

It's actually worn grooves in the Al.

Would rounding and polishing the butt of the bolt where it contacts the Al do any damage to the bolt? It doesn't look like it is critical to the function of the bolt, but I don't want to trade one problem for another (unless it's a lesser problem I get for my trouble).

[gunnut1]

Here in lies the problem. Up till now, there is NO long term information on the Williams receivers that we all got suckered into and bought. They started to fail before anyone had a long term information. What do you do about your problem? Unless someone has some long term information and data on these receivers, I don't know. I would bite the bullet and take the Williams off and put on a steel receiver. Like the other poster said, why not just use it a pistol caliber.

I might be totally wrong here but I would guess that the bolt will keep wearing through the aluminum till it finally just wears a hole through it. The bolt is not held captive in the carrier except when it is locked.

Don't know what to tell ya bud. I do not have a solution.

[Brett]

Could you inlay a thin piece of high tensile steel where it makes contact?

[gunsmith_tony]

Originally posted by hso
It's actually worn grooves in the Al.

Would rounding and polishing the butt of the bolt where it contacts the Al do any damage to the bolt? It doesn't look like it is critical to the function of the bolt, but I don't want to trade one problem for another (unless it's a lesser problem I get for my trouble).

Now don't be fooling around with that bolt. It's just minding it's own business...doing what it's 'sposed to be doing. It was NOT designed to be used in an alloy receiver. The alloy receiver is the problem...not your bolt.

[hso]

http://thehighroad.org/attachment.php?attachmentid=42016&d=1152494593

If I break the rear lower corner and polish it will it cause function problems?

[gunsmith_tony]

That area you've marked in red is where the bolt contacts the face of the locking shoulder. That surface integrity is pretty darn critical. I STRONGLY advise against doing this.

[ggiilliiee]

raspeguy ....+1....the only thing i would chek if doing the work raspeguy suggests is to see if there is any excessive slop when in lock when pushing the bolt bottom up from the magwell ...although it would have to be unusually excessive to cause any problem ..imo.with the light break edje ....ya should be just fine ........as an after thoght check it to see if it is warped in any way from machining ....worn end mills can push thin areas like that out of flatness if the tool was dull or chipped ...if so maybe you can put a flat block of steel there and give it a straightening whack ...mesure from the top surface of the rec to the flats to see if there is any deviation from side to side ya may wanna chek for binding in the rec carrier lug slots at the point where it gouges ...may need some relief at the top of the slot surface .....any way listen to raspeguy ...he knows what hes doing.......

[hso]

Let me see if I've been thinking about this wrong.

The bolt isn't supposed to "tilt" at any point in it's travel. It is supposed to either be locked or not into the carrier, but all movement of the bolt is in line with the movement of the carrier.

The "tilt" is due to the wear in the receiver. Since the bolt isn't locked in the carrier as it come back it allows the thing to tilt down into the groove.