How to Properly Polish a Feed Ramp

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Nice video. I do this to all my feed ramps and works great. Never tried to polish inside the chamber, may give it a try.
 
BOOGIE the oily said:
Great video, thanks.:)
But you scared me a bit with the speed of your air grinder. Doesn't the barrel get too hot, by working that fast?
Click to expand...
Lol, no the part will not heat up to anywhere near the heat produced by a fired round, and I use a electric foredom rotary tool not air grinder. I like electric because I can control the speed with my foot pedal.
 
Sorry, but I would NEVER do that to the chamber.
What you end up with is an oversize chamber, plus your round can now seat too deeply.
Should a chamber actually NEED polishing, it shouldn't be polished at full speed, with that compound, for that length of time.
 
Bill ,you're right.
I do it only to fix problems , with abrasive paper .Finer than 400 grit is only for show .Go back and forth parallel to the bore.
Examine all areas for burrs as a burr of even .001" can cause feed problems.
 
Heck of a welcome,huh!? Please understand its not personal.
The content of your vids is .."controversial".
The engineering requirements on your chamber include size (length and diameter) Form (roundness,cylindricity" )Location/orientation,and surface finish.
Same with the ramp. I'd guess something like a 63 rms finish,and I'd bet it gets monitored at Glock with a profilometer.
I'd bet the gun was in spec.

"Ease of extraction?" With most semi-autos,even war finish chambers,what happens if you remove the extractor?And fire a round? Will it stay in the chamber? I'm thinking its coming out,blowback style.It will probably jam,because without the extractor,the ejector won't work.

The reamer left a round,true chamber to size.Did you use pin gauges to measure the dia before and after? Don't assume. What about taper,or out of round,or belling,or jugging?? We probably don't have an air gauge...

It would be interesting to set your barrel up in my Harig index fixture,true to a pin gauge in the bore,and see what the indicator say happened in the chamber.

Glocks have been known to bulge or blow cases from lack of case support.

Would you suppose your nice radius blend gives about .030 less case support?

You might be able to sell the shiny,but it comes at the price of form and dimension.
Think microscopic on the tool finish. What is the chamber as machined? Little lines go around the chamber like screw threads...sort of.They have peaks and valleys.
Assuming no major flaws,we might just cut the peaks off to plateaus. Take the hair off,if necessary.

Now,when polishing,what do you do when you change grit? Change direction. You want to cross the lines you are trying to remove.That felt and compound is traveling in the same direction as the cutter did,and it will polish down in the valleys,too.
How do I know this? I spent many years building plastic injection molds.
I was sent to Chicago by my employer to understudy a Master Tool and Die Finisher. He was polishing coining dies for a mint when I arrived.

Plastic molds have requirements similar to a chamber.Form and accuracy must be held. Appearance is critical,especially on clear parts. And those plastic walls,injected at shotgun chamber pressures really want to get stuck in the mold.

The basic technique you might try is"draw stoning". Parts come out of a mold in "direction of draw" That would be the stone stroke direction.

You might use a 600 or 800 grit to start on the ramp. Gesswein or equiv polishing stone.Lay it flat on your work and stroke. The stone will break down to conform. The high spots will come off first. Watch the low spots evenly fade.

In the chamber? If you must,...I might use a very fine round stone,but probably a lap. Brass tubing would work. I'd use diamond polishing pasre myself,but you may try your Polish-O-Ray. Put some kerosene with it to make a slurry.
Rest your barrel in a vee block. You need good light. Maybe magnification.
Stroke the brass tube chargedwith slurry flat on the chamber wall.
You must see your surface texture. That is your "depth gauge" Strokea strip about 10 minutes wide on the clock face,full length of the chamber. Then rotate your work,and do another strip. All the way round. (First job the Master gave me to work on was a multi-cavity mold that made plastic caps for spray paint cans! They were sinker EDM finish.)
If your tool finish texture is .0006,from peak to valley,and you take nearly all of it,you might leave .0002 of valleys.. You use your tool finish rms as a gauge as you polish. You sustain form,and you hold dimension to the low spots of the tool finish.And,BTW,we planned our tool finish to hit the dimension...
"The secret of a good polish is a good tool finish"

Now,you have a surface held true by the form of the stone or lap,and all the lines go the same direction as the feeding ammo.(Or extracting)
You knocked the high spots off,leaving a trace of the low.

I don't care if its shiny or not. Its smooth.

If you must buff it a few seconds,light pressure,fine compound,...I like an end brush,myself,for the ramp.Actually a nylon pistol brush and a bit of compound would cross my stone marks if you don't have polishing brushes. . Just a few seconds at maybe 300 rpm.

FWIW,when I cut a chamber,I might go back in with a soft,fine stone.(or not!) The finer small Sunnen hone stones work pretty good.Or I super glue a bit of Gesswein stone on a stick of brass . 600 grit or finer. I run the lathe slow,and stroke in and out. Look real close,you see cross hatch.And I might be in there 20 seconds.Less is more.
I DO NOT wind the lathe up and go in with sandpaper on a stick.

Here is an old trick. The mechanical pencils with the thin lead. Hard lead is best..If you use that as a probe,dragging it on a chamber wall or ramp..you'd be surpised how you can feel any glitch.If the pencil won't feel it,your bullet/brass wont feel it. And it won't leave a scratch.
 
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I've polished a bunch of those over the years, but just the ramps and along the entry area into the chamber. I prefer to use a polish called Zam...which is very fine. An old gunsmith years ago told me about polishing things like that, without removing appreciable material, and I've always adhered to that theory. You are polishing, not grinding or sanding the material away. I see no problem with the way it was done in the video.
 
Bill DeShivs said:
Sorry, but I would NEVER do that to the chamber.
What you end up with is an oversize chamber, plus your round can now seat too deeply.
Should a chamber actually NEED polishing, it shouldn't be polished at full speed, with that compound, for that length of time.
Click to expand...
Sorry Bill, but I will have to disagree with you there friend. You are not removing any material simply polishing the surface does not take much time to polish. I can guarantee you if you take chamber measurements before and after there would be no difference. Danger zone is if you went crazy with some aggressive abrasives or sandpaper that will actually remove and you remove several thousands now your running into problems because you can cause cracked and split casings when you fire your weapon. But using a ultra fine compound like the brownells Polish O Ray 555 won't really remove material from the chamber.
 
HiBC said:
Heck of a welcome,huh!? Please understand its not personal.
The content of your vids is .."controversial".
The engineering requirements on your chamber include size (length and diameter) Form (roundness,cylindricity" )Location/orientation,and surface finish.
Same with the ramp. I'd guess something like a 63 rms finish,and I'd bet it gets monitored at Glock with a profilometer.
I'd bet the gun was in spec.

"Ease of extraction?" With most semi-autos,even war finish chambers,what happens if you remove the extractor?And fire a round? Will it stay in the chamber? I'm thinking its coming out,blowback style.It will probably jam,because without the extractor,the ejector won't work.

The reamer left a round,true chamber to size.Did you use pin gauges to measure the dia before and after? Don't assume. What about taper,or out of round,or belling,or jugging?? We probably don't have an air gauge...

It would be interesting to set your barrel up in my Harig index fixture,true to a pin gauge in the bore,and see what the indicator say happened in the chamber.

Glocks have been known to bulge or blow cases from lack of case support.

Would you suppose your nice radius blend gives about .030 less case support?

You might be able to sell the shiny,but it comes at the price of form and dimension.
Think microscopic on the tool finish. What is the chamber as machined? Little lines go around the chamber like screw threads...sort of.They have peaks and valleys.
Assuming no major flaws,we might just cut the peaks off to plateaus. Take the hair off,if necessary.

Now,when polishing,what do you do when you change grit? Change direction. You want to cross the lines you are trying to remove.That felt and compound is traveling in the same direction as the cutter did,and it will polish down in the valleys,too.
How do I know this? I spent many years building plastic injection molds.
I was sent to Chicago by my employer to understudy a Master Tool and Die Finisher. He was polishing coining dies for a mint when I arrived.

Plastic molds have requirements similar to a chamber.Form and accuracy must be held. Appearance is critical,especially on clear parts. And those plastic walls,injected at shotgun chamber pressures really want to get stuck in the mold.

The basic technique you might try is"draw stoning". Parts come out of a mold in "direction of draw" That would be the stone stroke direction.

You might use a 600 or 800 grit to start on the ramp. Gesswein or equiv polishing stone.Lay it flat on your work and stroke. The stone will break down to conform. The high spots will come off first. Watch the low spots evenly fade.

In the chamber? If you must,...I might use a very fine round stone,but probably a lap. Brass tubing would work. I'd use diamond polishing pasre myself,but you may try your Polish-O-Ray. Put some kerosene with it to make a slurry.
Rest your barrel in a vee block. You need good light. Maybe magnification.
Stroke the brass tube chargedwith slurry flat on the chamber wall.
You must see your surface texture. That is your "depth gauge" Strokea strip about 10 minutes wide on the clock face,full length of the chamber. Then rotate your work,and do another strip. All the way round. (First job the Master gave me to work on was a multi-cavity mold that made plastic caps for spray paint cans! They were sinker EDM finish.)
If your tool finish texture is .0006,from peak to valley,and you take nearly all of it,you might leave .0002 of valleys.. You use your tool finish rms as a gauge as you polish. You sustain form,and you hold dimension to the low spots of the tool finish.And,BTW,we planned our tool finish to hit the dimension...
"The secret of a good polish is a good tool finish"

Now,you have a surface held true by the form of the stone or lap,and all the lines go the same direction as the feeding ammo.(Or extracting)
You knocked the high spots off,leaving a trace of the low.

I don't care if its shiny or not. Its smooth.

If you must buff it a few seconds,light pressure,fine compound,...I like an end brush,myself,for the ramp.Actually a nylon pistol brush and a bit of compound would cross my stone marks if you don't have polishing brushes. . Just a few seconds at maybe 300 rpm.

FWIW,when I cut a chamber,I might go back in with a soft,fine stone.(or not!) The finer small Sunnen hone stones work pretty good.Or I super glue a bit of Gesswein stone on a stick of brass . 600 grit or finer. I run the lathe slow,and stroke in and out. Look real close,you see cross hatch.And I might be in there 20 seconds.Less is more.
I DO NOT wind the lathe up and go in with sandpaper on a stick.

Here is an old trick. The mechanical pencils with the thin lead. Hard lead is best..If you use that as a probe,dragging it on a chamber wall or ramp..you'd be surpised how you can feel any glitch.If the pencil won't feel it,your bullet/brass wont feel it. And it won't leave a scratch.
Click to expand...
I see where you are coming from friend and I agree in parts of what you say. And yes a firearm will extract without a extractor do to blow back but the extractor job is simply to hold the casing long enough to hit the ejector and knock the spent casing out of the firearm. But without the extractor you will have erratic ejection.
 
I did not view the video
I do not think for any of my store bought guns I would mess with the chamber on purpose... if it is malfunctioning and under warranty.. you get the idea

ON the other hand I have a CZ 75 9mm and a Tarus PT 1911 .45 that did not eat SOME ammo as well as others...internet search suggested dragging FEED RAMP... within my skill set to polish... problem solved...for me

Dremel, felt and cloth buff, various compounds, mirror smooth....happiness....I very seriously doubt I removed .005 metal...but did make each able to eat all the cheap crap ammo I am feeding them
 
Here is an indisputable fact:

You can not polish steel without removing metal.

I am very familiar with the polishing compounds you mention and the Foredom flexible shaft machines- I have 5 of them in my shop.

I do more metal polishing in a week than most people do in their lifetimes.

Running a felt bob with 555 polish at full speed for that length of time will remove a CONSIDERABLE amount of metal- especially since chambers don't need polishing. And it can bevel the chamber mouth, which can cause deeper cartridge seating and excessive pressure when firing a cartridge that is jammed into the beveled mouth.

That's the trouble with Youtube-everyone thinks they are an expert.
 
Bill is right on this. By polishing metal, you are removing it regardless. I would not touch a feed ramp unless I were having issues with one. In the past, I have encountered some chamber issues with burrs or other such that had to be removed (in school for gunsmithing). I always started with the lightest abrasive available, and always by hand. Typically I would use ceramic slip stones, and I would also use these for feed ramp polishing but I would only ever use them in a chamber if there was a burr or other material that had to be removed. I don't think I would ever use a dremel on the inside of a chamber. I think there are just too many unknowns.
 
Bill DeShivs said:
Here is an indisputable fact:

You can not polish steel without removing metal.

I am very familiar with the polishing compounds you mention and the Foredom flexible shaft machines- I have 5 of them in my shop.

I do more metal polishing in a week than most people do in their lifetimes.

Running a felt bob with 555 polish at full speed for that length of time will remove a CONSIDERABLE amount of metal- especially since chambers don't need polishing. And it can bevel the chamber mouth, which can cause deeper cartridge seating and excessive pressure when firing a cartridge that is jammed into the beveled mouth.

That's the trouble with Youtube-everyone thinks they are an expert.
Click to expand...
I guess we will just agree to disagree on this subject. As far as Expertise I do consider myself somewhat of a expert I graduated from the Colorado school of trades as a gunsmith, apprenticed under a great local gunsmith for a few years before branching out on my own and forming my own gunsmith shop and I would have continued running my business if not for some medical issues I have. But your more than welcome to watch my videos and give your opinions friend. This is the United States of America and one of the best things we have is the right to our opinions and freedom of speech.
 
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