Funny thing happened when I was cleaning my .45

[stevie_d_64]

I broke down "Sledgehammer" and was running the brushes and swabs through the barrel and noticed that there are some interesting striations, very slight ripples, for lack of a better word, in the grooves , not the lands of the barrel...

Very slight, but I did notice this...Any takers???

It's a Springfield 1911 A1, BTW...

I don't think it is a real problem, but I wanted to see if anyone else has ever seen this before...I am not sure it is anything serious, but it may be a manufacturers "personality" defect in the barrel, it may not be, I just don't know...

BTW, the ripples are perpendicular to the direction of travel down the barrel...

[jimlongley]

Sounds like tool marks to me.

[mr surveyor]

Sounds like tool marks to me.

I agree. I noticed the same thing in a new Airweight 637 a couple of years ago. After a couple hundred rounds the barrel ended up mirror polished.

New barrel?


surv

[stevie_d_64]

Tool marks...Probably...

I've got about 2500 rounds through it, so I am not sure that it is something serious to effect performance, accuracy or any potential FTF's...

I tried some (of what I thought might be good) digital pictures, but the flash kicked in on a few and blasted the images, and when the flash was turned off, you couldn't see it...

I think I should be glad it still works...Besides I need to pick up a couple of back up barrels anyway...Gunshow in Pasa-git-down-dena this next weekend...See who's selling wares then...

[MoJo]

tool marks for sure. With 2500 rounds through the gun I'm surprised they are still there. You never noticed them in the past? Have you been shooting FMJ or lead bullets mostly?

[joe817]

They're called "chatter marks". It occurs during the rifling process. As I understand it, and I'm no expert, it occurs when the tooling machine is rotating at to high of an r.p.m. when cutting the lands and grooves. I have them in my Govt. .380. as well.

Other than that, I don't know much about it. I'd think that chatter marks affect accuracy. And I've heard that with enough shooting those chatter marks are worn off. But with 2,500 rounds through your barrell...well gee. I dunno.

I know gunsmiths have a procedure called "firelapping" that's supposed to eliminate that. But I do not know how effective it is.

That's the sum total, and probably then some, of my knowledge of "chatter marks".

[Keith B]

I'd call Springfield and ask them. They are super on their customer service, and I have never had them fail to answer a question. If there is concern over them, I'd bet they will either take the gun back and rework the barrel or provide a new one without the chatter marks, since their guns have a lifetime warranty.

[The Annoyed Man]

My Springfield Loaded 1911 has something similar, and the round count is unknown. I've probably shot 700-800 rounds through it. I bought it from HighVelocity; he shot a lot of rounds through it, and he's not the original owner. The barrel is in good condition and the pistol shoots fairly accurately. To me, they are not so much marks, as they are a "rippled" look to the shininess of the metal in the grooves. It doesn't look "rough," just kind of "uneven." My guess is that there must be variations on the order of .0001" in the depth of the grooves — not enough to affect the accuracy, but enough to change the way the metal reflects light.

I noticed exactly the same phenomenon just the other day in a friend's new Kimber Pro Carry II barrel. That pistol was new and had just been to the range for the first time, not more than 100 rounds or so, and I was showing him how to field strip and clean his gun.

Come to think of it, both barrels I noticed it in were Stainless. I've never seen the phenomenon in a carbon steel barrel. Perhaps it is there, but the barrels just aren't shiny enough inside to notice it? Or, perhaps there is something different about the nature of stainless versus non-Stainless steels. I seem to remember once reading a long time ago that the trade off was that stainless barrels distribute heat more evenly (hence improved accuracy), but that stainless steel is slightly softer, so stainless barrels don't last as long. I have no idea if this is true or not, as I've never worn out the barrel of any gun.

[tomc]

Ya know, Steve, as you get older, the eyes begin to fail and start to play tricks on you. I guess the eyes are the third thing to go!

Sorry, Steve. I just couldn't resist.

Tom

[jimlongley]

There is a school of thought among long range target shooters, that "lapping" a bore will improve accuracy by a measurable amount.

This is not a comprehensive description of the process, merely an overview.

This process consists of polishing the bore with successively finer grades of compound on a "slug" or series of slugs that fit the bore almost perfectly, ridding it of tool marks which would tend to pick up fouling and change the internal ballistics from shot to shot. Purists insist that the polishing should take place from breech to muzzle only, that is; the slug should be inserted at the breech and pushed to the muzzle, remove, rinse, repeat, not scrubbed back and forth as many people do when cleaning a gun.

Ideally the lapping process should leave the bore mirror smooth, with no tool marks and a very slight taper from breech to muzzle.

-------------------------------------------------------------------

Years ago, my barber and I, our wives, and our kids, shot on a gallery rifle league together. I dropped by his house one night to have a look at a rifle he was offering for sale and found him in his basement workshop busily lapping the bore of his prize .22 target rifle. This guy could already shoot better standing than I could prone, well almost, and he was trying to improve his accuracy at 50 feet, by lapping the bore. To be honest, he also used to compete at 100 yards in smallbore, but . . .

[MoJo]

You may want to look into TUBB FINAL FINISH This is a series of bullets that are coated with lapping compound that you fire through your barrel to smooth out imperfections.

[Dragonfighter]

My Springfield Loaded 1911 has something similar, and the round count is unknown. I've probably shot 700-800 rounds through it. I bought it from HighVelocity; he shot a lot of rounds through it, and he's not the original owner. The barrel is in good condition and the pistol shoots fairly accurately. To me, they are not so much marks, as they are a "rippled" look to the shininess of the metal in the grooves. It doesn't look "rough," just kind of "uneven." My guess is that there must be variations on the order of .0001" in the depth of the grooves — not enough to affect the accuracy, but enough to change the way the metal reflects light.

Are the barrels CRS or drop forged?

[stevie_d_64]

I knew someone could come in here with that machinists term for this issue..."Chatter"...Good stuff!!!

I really do not believe it has effected the performance or accuracy of the pistol...

And I did just happen to notice it, besides the middle-age of the eyeballs (tomc! )...

I am going to get some direction from the Springfield customer service folks and see what they recommend...I mean, I'll go ahead and buy another barrel from them, just because I believe this may just be more cosmetic than a real problem with the pistol...

Question though, does anyone believe that if I put a custom, or match grade barrel in this pistol, would that void the life-time warrantee??? I'm thinking no, but you never know how some manufacturers feel about it...I mean you are only swapping out a barrel (part) and not doing anything to (physically) modify the overall construction of the gun or it's basic performance...

I'm also a believer of "if it ain't broke, don't fix it" mentality...

I'll see what the folks at Springfield say tomorrow...Keep y'all posted...

[stevie_d_64]

You may want to look into TUBB FINAL FINISH This is a series of bullets that are coated with lapping compound that you fire through your barrel to smooth out imperfections.

Interesting...

[mr surveyor]

if it shoots good.... I'd shoot it as is.