lugs galling on BAT MB bolt

[Webster]

I don't know anything about Mil-Comm TW25B. I don't know if the MIL Spec means it contains EP additives. It may just be a quality general purpose gun lube? For bolt lug protection you need a grease that is called Extreme Pressure (EP) usage. Grease called extreme usage doesn't mean it contains EP chemicals. Extreme usage may be sales lingo?

The pressure when the gun is fired cannot produce galling. There has to be high contact pressure when the bolt is rotated and the lug and receiver slide against each other. Is the bolt below some hardness spec.? Talk to the BAT people about your problem. Ask BAT to verify it's properly made. Who knows they may replace it if your lucky. If the lugs are galled the receiver must be galled also. Your rifle may work without problems if you have not lost head space?

The only grease I could find at Auto Zone rated EP was Mobil 1 Synthetic Grease. I put a small amount of this grease on my bolts lugs and bolt cocking ramp every time I go to the range. The rotary sliding motion of the lug contact probably wipes the grease off quickly. EP chemicals give extra protection when there are high contact loads, differential gears, wheel bearings ect.

Mobil Delvacâ„¢ Xtreme Grease
Mobil Delvac Xtreme Grease is an extra high performance extreme-pressure grease. It is an NLGI 2 grade and is manufactured with a proprietary, high-temperature lithium complex thickener system.
It exhibits excellent resistance to softening under severe working and provides good adhesion and cohesion. An extreme-pressure additive provides exceptional protection against wear and shock loads, while additional additives enhance resistance to high-temperature oxidation and protection against rust. Other formulation features provide very good resistance to water wash, and long service in bearings operating at high temperatures. This heavy-duty, severe-service grease has outstanding structural stability and chemical stability, will not corrode steel or copper bearing alloys, and is compatible with conventional seal materials.

Gunsmiths and store salesmen are not experts on lubricants. A gunsmith may know from experience what seems to work. I wouldn't use anything that wasn't rated "Extreme Pressure (EP)".


http://www.mobil.com/USA-English/Lubes/PDS/GLXXENGRSMOMobil_1_Synthetic_Grease.aspx
Mobil 1 Synthetic Grease
High performance automotive grease
Product Description
Mobil 1 Synthetic Grease is an NLGI No 2 high-performance automotive grease which combines a synthetic base fluid with a lithium complex soap thickener. The thickener system provides a high dropping point, while additives impart optimum extreme-pressure properties and excellent resistance to water wash, and outstanding protection against rust and corrosion. Mobil 1 Synthetic Grease has excellent structural stability. The synthetic base oil used in Mobil 1 Synthetic Grease gives it excellent performance properties at both high and low temperatures. High structural shear stability coupled with a high performance base oil make Mobil 1 Synthetic an outstanding automotive grease.
Features and Benefits
Mobil 1 Synthetic Grease provides the following advantages and benefits:
Features Advantages and Potential Benefits
All-purpose automotive service Certified to the NLGI GC-LB specifications for both chassis and wheel bearing lubrication
Wide Operating range -40 C (- 40 F) to 150 C (302 F)
Excellent resistance to rust and corrosion Longer life of bearings and chassis lube points
Outstanding structural stability Ability to provide effective lubrication over extended periods of time
Excellent wear protection under heavy loads Provides bearing protection while cornering and other conditions where bearings temporarily experience heavy loads.
Excellent resistance to water wash Withstands the effects of water washout from heavy rain storms or other high water wash events.
Applications
Mobil 1 Synthetic Grease meets the requirements of the National Lubricating Grease institute (NLGI) performance classification GC-LB. It is recommended for automotive applications at both high and low temperatures. It is particularly suited for applications such as disc brake wheel bearings and ball and steering joints. It will provide outstanding bearing protection under heavy loads at any highway speed, and where moisture or condensation is a factor.


http://www.mobil.com/USA-English-
Mobil Delvacâ„¢ Xtreme Grease
LCW/heavydutyengineoils_products_mobil-delvac-xtreme-grease.aspx
It is recommended for use in heavy-duty trucks, especially hinge and bucket pins, U-joints, and fifth wheels. It is also recommended for construction and mining sector applications, particularly for the lubrication of plain and antifriction bearings in contractor and mining vehicles working under severe operating and weather conditions. Mobil Delvac Xtreme Grease is also recommended for use in heavily loaded industrial bearings. The recommended application temperature range is -20°C to +175°C.

I didn't read your letter to BAT before I wrote this. It's painful to review 46 replies before I write something. Bat's reply sounds good. A tight case when closing the bolt. The load on the lugs has to come from some where when the bolt is moving. It's unfortunate they don't use harder metal to make these parts. I forgot to add that some EP chemicals form a layer that bonds to the metal. It doesn't wipe off.



Check this out
https://www.youtube.com/watch?v=VYTT8igfFeg

 

[Webster]

Cast metals are the only metal with pores. Forging and rolling closes any pores in wrought metals.

 

[lrgoodger]

"


Seriously? You need someone to tell you to use a good lube on your 1400$ action. Wow!!

If you read the whole thread, you saw that I lubed the bolt every time I cleaned (every 50 rounds). Bruce said it didn't really matter much what lube you use because it just gets wiped off the lugs the first time you close the bolt. I had realized that from the beginning, but I lubed anyway because it seemed that at least a few molecules must get between the surfaces, and that was better than nothing.

I would say you stuck a case at one time or another " we have all done this" and you didn't get it all cleaned out. Ive been there and done that myself. Good luck.

Nope. Never stuck a case in that action.

Some lessons in life cost you some cash. Really good lessons in life cost you a lot of cash! Lee

Actually it didn't cost me anything. I brushed the high spots off the galled surfaces and the galling stopped. Headspace has remained the same and it still shoots as good as it ever did. I never sent it for repair. The only ill effects are the mental distress I suffer each time I see that galling.

 

[lrgoodger]

Is the bolt below some hardness spec.? Talk to the BAT people about your problem. Ask BAT to verify it's properly made.

This also was discussed in my thread with BAT. My action and bolt now sport the identifying dimples in the photos, thanks to a friend of mine who has a hardness tester. They checked out to the specs Bruce gave me. He seemed a little miffed at my suggestion that it might not be up to snuff, but I pointed out to him that I was not implying anything. I was just being thorough. People can get distracted in the middle of doing things at any factory.

 

[gmorganal]

I have been using Pro Shot's Pro Gold on the lugs of all my bolt action rifles for the past decade, never had a problem with galling. I'd be interested in knowing if anyone has had any difficulty using Pro Gold or anything to be aware of.

 

[Webster]

I have a Rem 700 I bought in 1972. It's used for casual BR and GH hunting. For 38 yrs I never lubed the bolt lugs and I don't have galling. The bolt has seen about 15-20 thou rounds fired with 3 barrels. There are striations on the lugs that I would consider normal wear. Galling looks like plastic flow or smearing, not straight striations. I just started putting grease on the lugs 3 yrs ago. After loading about 3 rounds the smoothness from the grease seems to go away. I don't think most people understand how soft the bolt and probably the receiver are.

Galling can only be caused by something increasing the force between the bolt lug and the receiver contact. You cannot get galling with light contact pressure. The only sources of high contact pressure I can think of are:
1. The shoulder is being pushed back a lot by the bolt camming action.
2. The bullet is being seated hard into the rifling by closing the bolt.
3. Hot loads that stretch the case.

The way I adjust my shoulder bump is by feel. I use the method in Tony Boyers book on p. 120. I take the firing pin assembly out of the bolt. Adjust the FL resizing die until it touches the shell holder then back the die out about a 1/4 turn. Size a fired case and put it in the rifle. If it takes any effort to close the bolt, turn the die down about a 1/20 th. of a turn. Resize the case. Put the empty case in the rifle and close the bolt. Keep doing this until you get a setting so that the bolt falls to the horizontal position then closes with a little more effort.

I am going to call one of the engineers where I used to work and ask if there is a EP grease available of the type that forms an anti-wear film that bonds to the metal. The bolt /receiver contact rubbing may not be sufficient to get the chemical reactions that form an anti-wear layer on the part. These anti-wear chemicals are used a lot for automotive ring and pinion differential gear sets where the loads are extremely high.

 

[savagedasher]

When I went to gun smith school our instructor told us never lap the lugs to a mirror finish. The reason being mirror finish has no place for the lube adhere to. I watch many shooters using break clean, or carb cleaner. Both cut lubes. but leave resdue . When you put lubricant on resdue it doesn't bond to the metal. All mechanics learn that with wheel bearings. I think the same applies to bolts. If your using carb or break clean I would wash the resdue off with denatured alcohol then apply the lube and lap it in the surface by running the bolt. Larry

 

[M-61]

When I went to gun smith school our instructor told us never lap the lugs to a mirror finish. The reason being mirror finish has no place for the lube adhere to. I watch many shooters using break clean, or carb cleaner. Both cut lubes. but leave resdue . When you put lubricant on resdue it doesn't bond to the metal. All mechanics learn that with wheel bearings. I think the same applies to bolts. If your using carb or break clean I would wash the resdue off with denatured alcohol then apply the lube and lap it in the surface by running the bolt. Larry

Interesting analogy with wheel bearings. I understand the problems with leaving residue, however I can't think of two more polished smooth surfaces than the the bearing race and the ball, taper, or roller bearings. That they are 'packed' with grease separates them from comparison to bolt lugs in my opinion. I agree with you regarding 'residue".

 

[savagedasher]

When I went to gun smith school our instructor told us never lap the lugs to a mirror finish. The reason being mirror finish has no place for the lube adhere to. I watch many shooters using break clean, or carb cleaner. Both cut lubes. but leave resdue . When you put lubricant on resdue it doesn't bond to the metal. All mechanics learn that with wheel bearings. I think the same applies to bolts. If your using carb or break clean I would wash the resdue off with denatured alcohol then apply the lube and lap it in the surface by running the bolt. Larry

Interesting analogy with wheel bearings. I understand the problems with leaving residue, however I can't think of two more polished smooth surfaces than the the bearing race and the ball, taper, or roller bearings. That they are 'packed' with grease separates them from comparison to bolt lugs in my opinion. I agree with you regarding 'residue".

I didn't explain it well but you never wash A wheel bearing. and if you do you must pack it not just put grease on it. When you pack that means apply pressure. I hope that helps . Larry

 

[gunsandgunsmithing]

Most of the brake cleaners claim "no residue" left behind. http://www.berrymanproducts.com/products/brake-cleaner/


I suppose the term "no residue" could somehow be a relative phrase, but I'd bet it leaves less behind than holding the part in your hand, due to oils in our skin. I don't see it as a problem in terms of lube staying on the part, after being cleaned with brake cleaner and dried.


I'd also rather have the lug area cleaned with brake cleaner and re-lubed than to have it caked with debris.


I think we are splitting frog hairs and simply looking for a problem that doesn't exist in the context here.


Also, I can't agree about the smooth finish not being desirable in this context. Which would be more likely to gall, a smooth thread or a rough and ugly thread?


The problem of bolt lugs galling can be cured by surface treatment, such at nitriding, but just keeping them lubed well and not having excessive pressure from improper sizing has worked for longer than any of us have been alive.

 

[sigma2chi]

I have a BAT and I LOVE it.

This is what I use. Mil-Comm TW25b

http://www.mil-comm.com/index.php?option=com_content&task=view&id=46&Itemid=

I selected that because its what we use at work on our Dillon Mini Guns.

If it can handle 4000 rounds a minute it can handle a bolt at 5 rounds a minute max I think.

 

[CatShooter]

This is what Bat recommended to me a few months ago. http://www.midwayusa.com/product/573734/mil-comm-tw25b-gun-grease-1-1-2-oz-tube Its seems really thin.

I have received 2 actions from Bat within the last 3 months, and both came with a small sample of the above grease.

But I see from the Midway ad that this has been discontinued from the manufacture ???

Still available... just midway stopped carrying it.

http://www.amazon.com/Mil-Comm-TW25B-grease-tapered-tube/dp/B002T1ZW2E

 

[tmwinds]

No amount of lubricant of any kind can provide lubrication if you have 100% metal to metal contact and movement between the contact surfaces. Lubrication is provided when you have a thin cushion of lubricant between two moving parts. This lubricating film is not possible if there is 100% metal contact. An example would be the the relationship between the rod bearings and crankshaft in a modern internal combustion engine. In a proper setup the rod bearings never touch the crank jounals, it rides on a microscopic film of oil. The same applies to a gearbox, ring and pinion or any other moving part.

Bolt lug galling is caused by excess load pressure between the bolt lugs and lug recesses if the brass is not properly sized and bumped, hard bolt lift caused by excessive pressure, dirty lugs and recesses.

The lugs and recesses are camming devices. If excessive camming pressure is present then you will have galling.

 

[boltfluter]

No amount of lubricant of any kind can provide lubrication if you have 100% metal to metal contact and movement between the contact surfaces. Lubrication is provided when you have a thin cushion of lubricant between two moving parts. This lubricating film is not possible if there is 100% metal contact. An example would be the the relationship between the rod bearings and crankshaft in a modern internal combustion engine. In a proper setup the rod bearings never touch the crank jounals, it rides on a microscopic film of oil. The same applies to a gearbox, ring and pinion or any other moving part.

Bolt lug galling is caused by excess load pressure between the bolt lugs and lug recesses if the brass is not properly sized and bumped, hard bolt lift caused by excessive pressure, dirty lugs and recesses.

The lugs and recesses are camming devices. If excessive camming pressure is present then you will have galling.

Well said. My thoughts exactly.

Paul

www.boltfluting.com

 

[M-61]

No amount of lubricant of any kind can provide lubrication if you have 100% metal to metal contact and movement between the contact surfaces. Lubrication is provided when you have a thin cushion of lubricant between two moving parts. This lubricating film is not possible if there is 100% metal contact. An example would be the the relationship between the rod bearings and crankshaft in a modern internal combustion engine. In a proper setup the rod bearings never touch the crank jounals, it rides on a microscopic film of oil. The same applies to a gearbox, ring and pinion or any other moving part.

Bolt lug galling is caused by excess load pressure between the bolt lugs and lug recesses if the brass is not properly sized and bumped, hard bolt lift caused by excessive pressure, dirty lugs and recesses.

The lugs and recesses are camming devices. If excessive camming pressure is present then you will have galling.

I agree with what you say but the analogy really is different. Apples to oranges. The rod bearings (as well as the crank) do ride on a microscopic film of oil. This oil film is not due to an adhesive quality but rather oil pressure supplied by the oil pump. In a tranny or diff (except in exotic racing set ups) the lubrication is supplied by a splash system. We have neither in a bolt action.
You are right with the galling re:camming devices. Cleanliness is key, as is excessive pressures, and the bumping. And stainless still loves to gall.

 

[M14AMU]

Been using this for 50 years and never had a problem!

http://www.brownells.com/gun-cleaning-chemicals/oils-lubricants/lubricant-protectant-oils/lubriplate-130-a-mil-spec-grease-prod6525.aspx

 

[Hopkins]

Look under "NRA licensed gun care products" for the TW 25B grease at Midway

 

[expiper]

anyone who thinks that grease doesnt help with the smooth operation of moving parts obviously has little experience with firearms or anything mechanical,,,,,Roger

 

[gunsandgunsmithing]

anyone who thinks that grease doesnt help with the smooth operation of moving parts obviously has little experience with firearms or anything mechanical,,,,,Roger

Absolutely! But some lubes are much better than others. If you never have more than just spring pressure on the lugs, you could very well never realize it's importance or lack thereof, though. We tend to run things much closer in the accuracy game than the average guy/gal, and probably create the necessity for keeping the lugs lubed. I'm not saying that one should neglect lubing the lugs on any bolt gun, but honestly, wonder the percentage of hunting rifles that get proper care in this regard. I'd say something well less than 30%


That's where the types of steels, their heat treat, surface finish, or plating come into consideration. Tight fitting cartridges will generate far more pressure when camming the bolt closed than just spring pressure. Differential in the two mating surfaces and being smooth will help, regardless of lube. Personally, I'd like to see the inner abutments smooth and hardened to about 44-46Rc along with a bolt that is about the same, but is nitrided, which of course makes the surface much harder without making the lugs brittle.
Stiller plates many of his bolts and hard coat anodizes his aluminum action bodies.
The above is JMHO, everyone or anyone may feel differently.--Mike Ezell

 

[Webster]

The problem with putting anti-seize products on bolt lugs is that it quickly gets wiped off. Having said that I will continue doing it for a sense of doing it properly. The Remington owners manual states that you should put grease on the bolt lugs, cocking ramp and I think there is another place on the bolt. I think we have beat this subject sufficiently.