Barrel Bore Glaze

[JP65]

Had a customer with a barrel that was not performing as it used to........
After the usual inspection, I push several slugs thru it and found the bore glazed. I've seen worse, but it was definitely bad enough to effect how the bullet lubricant is carried down the bore.

Thought I would share a picture of the "before & after" results.
The owner will enjoy seeing it......hopefully others will find it of interest.

Jeff Patterson

 

[RFS99]

Had a customer with a barrel that was not performing as it used to........
After the usual inspection, I push several slugs thru it and found the bore glazed. I've seen worse, but it was definitely bad enough to effect how the bullet lubricant is carried down the bore.

Thought I would share a picture of the "before & after" results.
The owner will enjoy seeing it......hopefully others will find it of interest.

Jeff PattersonView attachment 6696

Jeff, I don't know what I'm looking at. Can you tell me what you see in the picture that indicates a glazed bore?

Thanks,

Larry

 

[Williwaw]

And a real newbie wonders what the process was between the before and the after. I'm guessing a light lapping with abrasives but guessing isn't knowing. Thanks.

 

[JP65]

Jeff, I don't know what I'm looking at. Can you tell me what you see in the picture that indicates a glazed bore?

Thanks,

Larry

Start with a clean bore, then you push about 3 bullet down thru the bore it will usually look very similar to the slug on the right.

Look close to the slug on the left......although the bore has been thoroughly cleaned and lubricated by pushing the 3 slugs thru it.....
Notice that the serrations on the left are actually shape like a triangle from scraping.....also if you look closely at the rifling cuts, you will notice that they are missing from the slug on the left and still present on the right slug.

I have seen it so bad that the serrations were completely gone and the bullet look like it had been chromed.

The scraping that effected the bullet on the left was a "glaze" condition that was removed with a light lapping.....
I couldn't see this "glaze" thru a bore scope......one can feel it while slugging and see it's effect on the slug.

Jeff

 

[RFS99]

Start with a clean bore, then you push about 3 bullet down thru the bore it will usually look very similar to the slug on the right.

Look close to the slug on the left......although the bore has been thoroughly cleaned and lubricated by pushing the 3 slugs thru it.....
Notice that the serrations on the left are actually shape like a triangle from scraping.....also if you look closely at the rifling cuts, you will notice that they are missing from the slug on the left and still present on the right slug.

I have seen it so bad that the serrations were completely gone and the bullet look like it had been chromed.

The scraping that effected the bullet on the left was a "glaze" condition that was removed with a light lapping.....
I couldn't see this "glaze" thru a bore scope......one can feel it while slugging and see it's effect on the slug.

Jeff

Jeff, as always, thanks for the information. I can now see what you mean in your picture.

Best regards,

Larry

 

[Lucky]

Start with a clean bore, then you push about 3 bullet down thru the bore it will usually look very similar to the slug on the right.

Look close to the slug on the left......although the bore has been thoroughly cleaned and lubricated by pushing the 3 slugs thru it.....
Notice that the serrations on the left are actually shape like a triangle from scraping.....also if you look closely at the rifling cuts, you will notice that they are missing from the slug on the left and still present on the right slug.

I have seen it so bad that the serrations were completely gone and the bullet look like it had been chromed.

The scraping that effected the bullet on the left was a "glaze" condition that was removed with a light lapping.....
I couldn't see this "glaze" thru a bore scope......one can feel it while slugging and see it's effect on the slug.

Jeff

It is amazing how much glazing built up in the barell. You could not see it , but when your performance starts dropping off , little by little , you know something is wrong , but you have no idea what. The glazing occurred not from lack of cleaning. I ran a brush down the bore after every card to maintain accuracy.
I am anxious to retest the rifle and see how it performs!
I would never have guessed that the barell was getting glazed , but I knew something was wrong.

 

[JP65]

I received a follow up report on the barrel that was de-glazed.....
Same ammo, rifle and barrel, but accuracy has returned.

Out his last 10 practice cards he shot 4 - 2400's and 1 - 2450.
His last match averaged 2337 with 16 X's....... customer's exact words...."it is shooting as good as it ever has".

So......if you had a killer barrel that has slowly lost it's mojo.......

JPatt

 

[14Copperhead]

JP65, I have a question for you about “Light Lapping”. Would JB Bore Bright or JB Bore Paste be best to do some light lapping? My Muller barrel has about 5,000 rounds through it now. I’ve been cleaning after every card I shoot with Boretech Rimfire Blend, more recently with Boretech C4 Carbon remover. Should the Light Lapping be done as a preventative cleaning process after each season?

Thanks,

 

[JP65]

Since this post was under the "Barrel Bore Glaze" ...... Iet me say that I've never been able to remove the "glaze" with anything other than casting a lead lap. "Light Lapping" is referring to the procedure (your not trying to remove or change the bore (barrel surface), just remove a glaze.

I have tried with things like JB bore paste etc. with no success.

I personally do not advocate the use of any type bore paste/polish other than maybe lightly in the chamber area only if you have a stubborn carbon build up.

A few patches wet with Hoppes # 9, followed by a few dry. Then if I have a carbon ring I need to clean and possibly some lead in the bore.....I will pull a .223 centerfire bronze brush about 4 to 6 times (wetting the brush with some Hoppes).....then finish with a few more wets and then the dry patches. ! Strictly pulling the brush, never pushing. Following this cleaning procedure along with never shooting my rifle so fast that the bore gets hot......I have no issues.

I'll say again.....I do not know exactly what causes "bore glaze". I have hypothesized that its possibly caused or contributed by certain type cleaning chemicals along with getting the bore too hot from fast shooting. ????? all I know is that........I change my cleaning to this method because Bill Calfee instructed me to........using Hoppes # 9, I have never since had bore glaze.

JPatt

 

[Shooter6]

Since this post was under the "Barrel Bore Glaze" ...... Iet me say that I've never been able to remove the "glaze" with anything other than casting a lead lap. "Light Lapping" is referring to the procedure (your not trying to remove or change the bore (barrel surface), just remove a glaze.

I have tried with things like JB bore paste etc. with no success.

I personally do not advocate the use of any type bore paste/polish other than maybe lightly in the chamber area only if you have a stubborn carbon build up.

A few patches wet with Hoppes # 9, followed by a few dry. Then if I have a carbon ring I need to clean and possibly some lead in the bore.....I will pull a .223 centerfire bronze brush about 4 to 6 times (wetting the brush with some Hoppes).....then finish with a few more wets and then the dry patches. ! Strictly pulling the brush, never pushing. Following this cleaning procedure along with never shooting my rifle so fast that the bore gets hot......I have no issues.

I'll say again.....I do not know exactly what causes "bore glaze". I have hypothesized that its possibly caused or contributed by certain type cleaning chemicals along with getting the bore too hot from fast shooting. ????? all I know is that........I change my cleaning to this method because Bill Calfee instructed me to........using Hoppes # 9, I have never since had bore glaze.

JPatt

I have a question about your statement “Strictly pulling the brush, never pushing”, is that accomplished from breach to muzzle or muzzle to breach ?

 

[JP65]

Pulling the brush from the muzzle back to the breach.