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Posted: 8/18/2026 11:33:36 AM EDT
[Last Edit: JHans7663][Edited]
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I have 2 chrome Microbest BCGs, both bought from one vendor about 4 months apart. I am unsure if they are from the same batch or not. They require cleaning and lube every range session. I can go shoot 30 rounds, the next day they are bone dry and crusty with carbon. They will not go into battery without assistance from the FA. It’s like every drop of oil is just gone. They require removal, a good scrape of crusty carbon, and a heavy re lubrication. I use Lucas extreme, slip EWL, and engine oil/grease mixtures. All 3 end up the same. My other BCGs will all hold onto lube and turn into a black oily/greasy mess. Out of habit I give them a little squirt of oil and keep partying. I’ve never had one get so dry that it won’t go into battery after just a magazine or two. Is this normal/common with chrome BCGs? Edit: Pics. Two photos of a chrome BCG next to the bathroom sink. That BCG has 40 rounds on it. One photo of a non chrome BCG that I wiped with my finger. It has 300 rounds and is still sloppy wet. Both BCGs were cleaned and lubed the same day. Both were very wet with engine oil/grease mixture lube. The chrome BCG barely got my fingers dirty. https://imgur.com/a/9eZsTM5 |
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Originally Posted By JHans7663: They’re discolored sort of. Elbow grease and carbon cleaner won’t quite bring them back to new color. I did try ultrasonic cleaning one and it brought it back to normal color. Brasso works well |
And then, he arrives at the last item on his bucket list...
| I'm guessing you mean 40 rounds since lubricating not 40 rounds since cleaning. I was asking about discoloration trying to figure out if it's actually chrome. Curious how many rounds on it? I usually shoot a few hundred rounds and wipe it down to a silver shine must be quite a few I imagine |
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Originally Posted By JHans7663: I have 2 chrome Microbest BCGs, both bought from one vendor about 4 months apart. I am unsure if they are from the same batch or not. They require cleaning and lube every range session. I can go shoot 30 rounds, the next day they are bone dry and crusty with carbon. They will not go into battery without assistance from the FA. It’s like every drop of oil is just gone. They require removal, a good scrape of crusty carbon, and a heavy re lubrication. I use Lucas extreme, slip EWL, and engine oil/grease mixtures. All 3 end up the same. My other BCGs will all hold onto lube and turn into a black oily/greasy mess. Out of habit I give them a little squirt of oil and keep partying. I’ve never had one get so dry that it won’t go into battery after just a magazine or two. Is this normal/common with chrome BCGs? Edit: Pics. Two photos of a chrome BCG next to the bathroom sink. That BCG has 40 rounds on it. One photo of a non chrome BCG that I wiped with my finger. It has 300 rounds and is still sloppy wet. Both BCGs were cleaned and lubed the same day. Both were very wet with engine oil/grease mixture lube. The chrome BCG barely got my fingers dirty. https://imgur.com/a/9eZsTM5 Try never dull. It takes the stains off of the end of stainless steel revolver cylinder. |
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If the bolt won't go into battery after one mag's worth of fouling, you have more problems than the BCG coating. Maybe the feed ramps have issues, maybe the carrier is dragging on the magazine, maybe the buffer spring is weak, or any other number of things, but that shouldn't happen dry or not. Regarding coating, without doing a strict comparison, it seems like phosphate holds lube about as well as chrome does, but after a few hundred rounds suppressed both get pretty dry and I still expect the gun to function. Chrome is easier to clean but I never clean anything anyway. |
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Originally Posted By jjz3: I'm guessing you mean 40 rounds since lubricating not 40 rounds since cleaning. I was asking about discoloration trying to figure out if it's actually chrome. Curious how many rounds on it? I usually shoot a few hundred rounds and wipe it down to a silver shine must be quite a few I imagine That is 40 rounds after cleaning AND lubing. Both of the chrome BCG I own are sub 1k rounds. |
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Originally Posted By Apple3_14159: If the bolt won't go into battery after one mag's worth of fouling, you have more problems than the BCG coating. Maybe the feed ramps have issues, maybe the carrier is dragging on the magazine, maybe the buffer spring is weak, or any other number of things, but that shouldn't happen dry or not. Regarding coating, without doing a strict comparison, it seems like phosphate holds lube about as well as chrome does, but after a few hundred rounds suppressed both get pretty dry and I still expect the gun to function. Chrome is easier to clean but I never clean anything anyway. It’s not an upper/lower issue. The issue will follow the chrome BCGs to what ever gun I move them too. They end up not going into battery due to how dry they get. The build up of carbon on the bolt gets so dry and crusty like that it does not want to slide in the carrier. I have to scrape off all the crud and liberally lubricate then it moves like normal. These chrome carriers are not easier to clean than my others. Hence why I’m here wondering if it’s normal or if this is a bad batch of chrome. |
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Originally Posted By -OdieGreen-: Weird. You can see matte chrome where you wiped it with your finger in the gun, but not after you cleaned it. Are you using motor oil as lube? The photo of the BCG in the gun is a normal BCM. That’s the BCM logo showing through. I was just comparing how dirty and wet that BCG is compared to the chrome one next to the white sink. . Both of those BCGs were cleaned and lubricated on the same day. Both were lubricated with a SOTARacha mix. The BCM has around 400 rounds and the chrome has around 40 rounds since cleaning. I have also tried my other usual lubes of Lucas gun oil and Slip EWL. They perform significantly worse on the chrome BCGs. |
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Just my take right or wrong. Different powders in different ammo produce different amounts of residue and different firearms blow back different amounts. Some powder residue seems worse on how long the lube stays wet than others do. Unless the same amount of the same lot ammo was shot in the same firearm with the two different bcg's it would be hard to reach any kind of conclusion. But somehow, I don't think chrome on the outside of a bolt carrier has some mysterious property that would allow it to make lube disappear or dry up. The lube would still be there somewhere even if not on the carrier. There is chrome on the inside of many carriers already anyway. Shiny chrome visually showing black residue better than a black carrier I understand. There is one powder I reloaded some 223 with that I will never use again because its residue seemed to dry out lubrication. Was a great powder for accuracy in the that load though. Just thought I would add that cleaning an AR with the gas port down instead of up might allow bore cleaning chemicals to run down into the base and gas tube and sit there waiting to blow back into the bcg and upper on the first shot. |
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Most of mine used to get dry, whether fired or not, when using CLP. I switched to Mobil 1. Last FRT session, the booth looked like a Diddy party and bitches several lanes over complained about oil splatter. My bolt was still wet when I cleaned it. 
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Preferred pronoun: MARINE
| Huh. I just cleaned a chrome BCG on an upper that I built recently. It only has maybe a few hundred rounds through it. I need to wring it out thoroughly so I'll keep an eye on how it holds up. |
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Originally Posted By j3_: Just my take right or wrong. Different powders in different ammo produce different amounts of residue and different firearms blow back different amounts. Some powder residue seems worse on how long the lube stays wet than others do. Unless the same amount of the same lot ammo was shot in the same firearm with the two different bcg's it would be hard to reach any kind of conclusion. But somehow, I don't think chrome on the outside of a bolt carrier has some mysterious property that would allow it to make lube disappear or dry up. The lube would still be there somewhere even if not on the carrier. There is chrome on the inside of many carriers already anyway. Shiny chrome visually showing black residue better than a black carrier I understand. There is one powder I reloaded some 223 with that I will never use again because its residue seemed to dry out lubrication. Was a great powder for accuracy in the that load though. Just thought I would add that cleaning an AR with the gas port down instead of up might allow bore cleaning chemicals to run down into the base and gas tube and sit there waiting to blow back into the bcg and upper on the first shot. I had questioned powders. Hadn’t gotten around to testing much. one is in a varmint gun. It sees a diet of 77 SMK/TMK over 8208 XBR. It doesn’t get as dry. I actually haven’t pulled it out lately I need to see what it looks like. The one in the pics came out of a gun shooting bulk handloads. I can’t remember which powder is in this current batch but it’s 95% chance of being CFE223 or BLC2. |
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Originally Posted By JHans7663: I had questioned powders. Hadn’t gotten around to testing much. one is in a varmint gun. It sees a diet of 77 SMK/TMK over 8208 XBR. It doesn’t get as dry. I actually haven’t pulled it out lately I need to see what it looks like. The one in the pics came out of a gun shooting bulk handloads. I can’t remember which powder is in this current batch but it’s 95% chance of being CFE223 or BLC2. CFE223 is one I used once and decided not to use again. |
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Originally Posted By Apple3_14159: If the bolt won't go into battery after one mag's worth of fouling, you have more problems than the BCG coating. Maybe the feed ramps have issues, maybe the carrier is dragging on the magazine, maybe the buffer spring is weak, or any other number of things, but that shouldn't happen dry or not. Regarding coating, without doing a strict comparison, it seems like phosphate holds lube about as well as chrome does, but after a few hundred rounds suppressed both get pretty dry and I still expect the gun to function. Chrome is easier to clean but I never clean anything anyway. Just bumping this post... Very important to look at other things. (Had a problem where one of my rifles would fail to extract most of the time. Some stove pipes. Finally noticed the roll pin in the buffer itself was sticking out just enough to occasionally catch on the buffer spring. I've never seen or heard of that before. So a new buffer it was) |
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Originally Posted By FVMC: Just bumping this post... Very important to look at other things. (Had a problem where one of my rifles would fail to extract most of the time. Some stove pipes. Finally noticed the roll pin in the buffer itself was sticking out just enough to occasionally catch on the buffer spring. I've never seen or heard of that before. So a new buffer it was) Originally Posted By FVMC: Originally Posted By Apple3_14159: If the bolt won't go into battery after one mag's worth of fouling, you have more problems than the BCG coating. Maybe the feed ramps have issues, maybe the carrier is dragging on the magazine, maybe the buffer spring is weak, or any other number of things, but that shouldn't happen dry or not. Regarding coating, without doing a strict comparison, it seems like phosphate holds lube about as well as chrome does, but after a few hundred rounds suppressed both get pretty dry and I still expect the gun to function. Chrome is easier to clean but I never clean anything anyway. Just bumping this post... Very important to look at other things. (Had a problem where one of my rifles would fail to extract most of the time. Some stove pipes. Finally noticed the roll pin in the buffer itself was sticking out just enough to occasionally catch on the buffer spring. I've never seen or heard of that before. So a new buffer it was) I've heard of it happening a few times over the years on el-cheapo commercial buffers... It turns out that there's a good reason that Colt does it the way they do on their buffers and preventing the roll pin from walking out is the likely reason.  Colt Buffer .719" Roll Pin vs Generic Buffer .688" Roll Pin  Colt Buffer Roll Pin and Buffer Weights Orientation Upon Reassembly  40 Year Old Colt Buffer Examination |
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Originally Posted By 556Cliff: I've heard of it happening a few times over the years on el-cheapo commercial buffers... It turns out that there's a good reason that Colt does it the way they do on their buffers and preventing the roll pin from walking out is the likely reason.  https://www.youtube.com/watch?v=NQJBlVivGiI https://www.youtube.com/watch?v=ctkvXAtJnNI https://www.youtube.com/watch?v=C8uVA03uzz0Probably more to what keeps a spec pin in place. On a spec one the hole in the bumper is not supposed to be larger than .124" which is .001" smaller than the minimum size hole some spring pin manufacturers recommend. The hole in the bumper can be as small as .120" on a spec one. The hole in the buffer body after anodizing can be as large as .129" but no smaller than .125". The .129" is the maximum hole diameter some spring pin manufacturers recommend for a 1/8" pin. I think the bumper needs to be made of the correct material and the hole sized correctly because it appears it does a lot for keeping the pin in place as it should be at least a .001" smaller on the hole than what is in the buffer body.. Not saying it could not happen, but I have never seen a pin walk out of a buffer far enough to hit/catch the spring. Have seen bumpers that broken into pieces or turned to goo as they deteriorated. |
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Originally Posted By j3_: Probably more to what keeps a spec pin in place. On a spec one the hole in the bumper is not supposed to be larger than .124" which is .001" smaller than the minimum size hole some spring pin manufacturers recommend. The hole in the bumper can be as small as .120" on a spec one. The hole in the buffer body after anodizing can be as large as .129" but no smaller than .125". The .129" is the maximum hole diameter some spring pin manufacturers recommend for a 1/8" pin. I think the bumper needs to be made of the correct material and the hole sized correctly because it appears it does a lot for keeping the pin in place as it should be at least a .001" smaller on the hole than what is in the buffer body.. Not saying it could not happen, but I have never seen a pin walk out of a buffer far enough to hit/catch the spring. Have seen bumpers that broken into pieces or turned to goo as they deteriorated. Originally Posted By j3_: Originally Posted By 556Cliff: I've heard of it happening a few times over the years on el-cheapo commercial buffers... It turns out that there's a good reason that Colt does it the way they do on their buffers and preventing the roll pin from walking out is the likely reason. https://www.youtube.com/watch?v=NQJBlVivGiI https://www.youtube.com/watch?v=ctkvXAtJnNI https://www.youtube.com/watch?v=C8uVA03uzz0Probably more to what keeps a spec pin in place. On a spec one the hole in the bumper is not supposed to be larger than .124" which is .001" smaller than the minimum size hole some spring pin manufacturers recommend. The hole in the bumper can be as small as .120" on a spec one. The hole in the buffer body after anodizing can be as large as .129" but no smaller than .125". The .129" is the maximum hole diameter some spring pin manufacturers recommend for a 1/8" pin. I think the bumper needs to be made of the correct material and the hole sized correctly because it appears it does a lot for keeping the pin in place as it should be at least a .001" smaller on the hole than what is in the buffer body.. Not saying it could not happen, but I have never seen a pin walk out of a buffer far enough to hit/catch the spring. Have seen bumpers that broken into pieces or turned to goo as they deteriorated. It's surprising how much thought went into a part that seems so simple. I've never seen a failure of a buffer in person, only here on the forums. It's always with very cheap bargain bin (likely Chinese) parts. Usually the bumper is a non standard color and so is the body of the buffer. It's one of the few parts that even I thought you could get away with not buying Colt as long as you avoided buying the obviously Chinese bargain bin junk. I have Damage Industries buffers in all my ARs and the roll pins in them are flush to the buffer body on both sides and the slot on the roll pins is oriented incorrectly and randomly on all of them. I plan to weed them out for Colt buffers at some point, but I am curious to see if any of the roll pins ever manage to walk out. I'll probably never shoot enough to ever see it happen, and I think that's probably the case for most people. |
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Originally Posted By mcantu: Roll back to a base line setup to remove variables. Use factory ammo, not reloads; use a real lube (a basic CLP at least), not a bubba'd up goop concoction from a YouTube channel; no can, if you've been using one From the original post I have already tried Lucas extreme and Slip 2000. What is a more real lube I should try? This whole issue is the reason I tried the engine oil/grease mixture to begin with. So far that mixture has been the best on these 2 BCGs. I have tried factory ammo. Wolf Gold and PMC Xtac. I have shot them both supressed and unsupressed. In both 5.56 and .300 BO. Same issue. The issue follows the BCGs not the guns they’re in. |
| It sounds like you're putting the oil/grease everywhere as opposed to exactly where you need it. For the BCG, you want to put grease/oil only on the four rails and on the bottom where the hammer rides. Put a lot on the cam pin, the spring on the extractor, and on the raised edge of the bolt. This should last for 1000s of rounds and shouldn't create a sloppy mess like your pictures. Oil on any other part won't really do much of anything. |
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Originally Posted By dalle0001: It sounds like you're putting the oil/grease everywhere as opposed to exactly where you need it. For the BCG, you want to put grease/oil only on the four rails and on the bottom where the hammer rides. Put a lot on the cam pin, the spring on the extractor, and on the raised edge of the bolt. This should last for 1000s of rounds and shouldn't create a sloppy mess like your pictures. Oil on any other part won't really do much of anything. If I only lube the rails and the bottom both of the chrome BCGs will be bone dry just like in the photos. There is not a shimmer of oil. And then they won’t go into battery because of the crusty carbon. The wet oily mess is just me running 1 chrome and 1 non chrome BCg through similar paces to compare. Both were cleaned and over lubed. The non chrome turned into a mess. The chromed is dried out. That’s what I’m trying to determine. Why do the chrome get dry and fail to go into battery? Why do my non chrome stay a wet mess? Same bottles of lube. Same or similar shooting conditions. |
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Originally Posted By j3_: Probably more to what keeps a spec pin in place. On a spec one the hole in the bumper is not supposed to be larger than .124" which is .001" smaller than the minimum size hole some spring pin manufacturers recommend. The hole in the bumper can be as small as .120" on a spec one. The hole in the buffer body after anodizing can be as large as .129" but no smaller than .125". The .129" is the maximum hole diameter some spring pin manufacturers recommend for a 1/8" pin. I think the bumper needs to be made of the correct material and the hole sized correctly because it appears it does a lot for keeping the pin in place as it should be at least a .001" smaller on the hole than what is in the buffer body.. Not saying it could not happen, but I have never seen a pin walk out of a buffer far enough to hit/catch the spring. Have seen bumpers that broken into pieces or turned to goo as they deteriorated. What you didn't mention is the size of the pin A nominal 1/8" slotted, tubular, spring pin diameter is 0.131 to 0.135. If you decide to use a coil spring pin the diameter range is 0.130 to 0.139. Worst case there is a 0.001" interference between the aluminum and pin and a 0.006" interference between the bumper and the pin. Big however, though. If you drive the steel pin out of an aluminum part, the hole is now bigger than it was when the pin went in and the pin is smaller. This is why it is recommended that the pin be replaced every time it comes out. They are cheap enough. |
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Originally Posted By JHans7663: If I only lube the rails and the bottom both of the chrome BCGs will be bone dry just like in the photos. There is not a shimmer of oil. And then they won't go into battery because of the crusty carbon. The wet oily mess is just me running 1 chrome and 1 non chrome BCg through similar paces to compare. Both were cleaned and over lubed. The non chrome turned into a mess. The chromed is dried out. That's what I'm trying to determine. Why do the chrome get dry and fail to go into battery? Why do my non chrome stay a wet mess? Same bottles of lube. Same or similar shooting conditions. Is your barrel ext full of crud? |
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I haven’t had any issues from my chrome but it’s more of a matte chrome from Expo. Maybe try that Bcg in a different gun and see if the problems follow it. I’ve definitely had NiB dry up and short stroke the gun after few hundred rounds so try and use a grease mixture (half Slip EWG half ALG go juice) on anything non phosphate. At this point I’m just buying traditional phosphate . |
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surprised to see this issue I like to get my match pistols hard chromed because they don’t rust, last a long time, and are super easy to clean this one was done by TRIPP RESEARCH others were done by METALIFE Attached File |
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Originally Posted By TGWLDR: It does look to be NiB honestly. Originally Posted By TGWLDR: Originally Posted By armsman: The BCG in the picture doesn’t look like a hard chrome BCG. It looks more like one of those nickel coated BCGs. It does look to be NiB honestly. I was thinking the same thing. |
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Originally Posted By armsman: The BCG in the picture doesn’t look like a hard chrome BCG. It looks more like one of those nickel coated BCGs. Could be. I have two new BCGs on order. If my issues go away with new BCGs these will go away. Hopefully the newborn will let me out of the house so I can go test them. 
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