Mythbusting? Can a bore be too smooth?

[Canuck Bob]

Research about lapping and polishing resulted in the statement that a bore can be too polished. My interest revolves around cast bullet shooting, including paper patch, but includes jacketed.

Confirmed or Busted?

Folks report barrels with problems lead less or not at all. Some report they copper foul less and reduce or eliminate cleaning other than carbon. I've tried a couple of cast bullet sites as well. Will report on the outcome.

Edit: This assumes a healthy polished bore not one ruined by bad lapping process'.

[TedH]

What do they say happens if it's "too smooth"?

[Chuck 100 yd]

NO! the smoother the better.
If you have one that is too smooth you can always leave it dirty and standing out in the rain for a few days.

[3leggedturtle]

Sure it can, and a "lady can be to pretty and outdoorsy too" . I am sure some i-net know it all probably has proof that a "too" smooth bore wont let the powder build up pressure because the bullet just glides out with no friction.

[Canuck Bob]

Guys, I understand the apparent absurdity to this. However it comes up as possible on some forums.

[Rusty]

The only way I could see it being too smooth would be if it were shot so much that it was turned into a smooth bore.

[Bronco]

Kinda like being too good a shot

[Old Ironsights]

I can only pray to develop a way to make a shotgun bore so smooth as to be frictionless.

I will be rich beyond dreams of Avarice.

And I can dream a lot...

[Chuck 100 yd]

Old Ironsights, Maybe you remember back in the late 70`s there was a company making 1100 and 870 barrels for trap guns that Had 12 ga. chambers and the rest of the barrel and choke were bored to 10ga. spec.
A friend (young lady ) had one and it shot and patterned very good and recoil in the 1100 was just SUPER soft, almost non existent when shooting 1 oz. trap loads but would grind up targets like a normal 12ga.

[mikld]

Yep, I read this question on another forum yesterday, and read some "yes barrels can be too smooth" posts, but didn't see any "why it's so" answers...

[AJMD429]

There are those 'polygonal' rifled barrels, and some that I think were sort of an elliptical cross-section that twisted as you moved along the bore axis. If those were ok, then it could be that the 'edge' of the rifling doesn't have to be sharp to engage and rotate the bullet.

[Canuck Bob]

This appears on the cast bullet sites. So far it seems to apply, if it is valid, to barrels polished to a level well beyond anything the vast majority will ever see. 600 grit surfaces seem to be the point were it is recommended to stop for lapping. It is nothing I'll ever have to worry about.

This was strictly an exercise in wondering if such a thing could be true. One thread mentioned that muzzleloaders can be too smooth as well.

One thing that did come up in research is that paper patching can result in very polished bores over time.

[Canuck Bob]

http://www.riflebarrels.com/articles/ba ... ouling.htm

Here Dan Lilja states clearly that a barrel can be too smooth and foul more. I suspect he knows a thing or two about gun barrels! He also states clearly that amateurs should not mess with custom barrels. He seems to indicate that is not the case with unlapped factory barrels.

[6pt-sika]

There's a lot written about breaking in barrels and polishing them .

I am of the opinion that both those things lessens the life of a rifle barrel .

My usual break in procedure for a new barrel be it factory or sutom is to shoot a single sahot clean it . Shoot a 3 shot group clean it . Repeat the 3 shot thing a couple more times and then start shooting a fouler followed by 3 or 4 3 shot groups and clean rerpeat the process .

Polishing , the whole idea of that makes me feel slightly ill . When you polish you are putting minute particles of some kind of light abrasive in the barrel . That goes against everything I have done in my life as far as rifle accuracy was concerned . It may be for some folks but I AM NOT one of them .

[6pt-sika]

http://www.riflebarrels.com/articles/ba ... ouling.htm

Here Dan Lilja states clearly that a barrel can be too smooth and foul more. I suspect he knows a thing or two about gun barrels! He also states clearly that amateurs should not mess with custom barrels. He seems to indicate that is not the case with unlapped factory barrels.

I have a Lilja barrel on one rifle and a couple Shilen barrels on others .

I am of the opinion when one buys a barrel blank from a custom barrel maker the barrel should be lapped when you receive it so why would you wanna polish/lap it anymore or shoot a whole bunch of shots supposedly breaking it in .

[6pt-sika]

This appears on the cast bullet sites. So far it seems to apply, if it is valid, to barrels polished to a level well beyond anything the vast majority will ever see. 600 grit surfaces seem to be the point were it is recommended to stop for lapping. It is nothing I'll ever have to worry about.

This was strictly an exercise in wondering if such a thing could be true. One thread mentioned that muzzleloaders can be too smooth as well.

One thing that did come up in research is that paper patching can result in very polished bores over time.

I do not agree with lapping/polishing bullets for cast bullets .

If the gun is old and or that rough shoot jacketed in it and get another similar gun for cast bullets .

There's a person and I use that term loosely on www.castbulletassoc.org/forum that is using furniture polish to do all his Handi Rifle barrels . I don't care for the guy personally and think his procedure is absurd . But there are others on that site that seem to go along with his idea .

[Canuck Bob]

Thanks 6pt, always respect your advice. I am going to try some fire lapping simply as an education and experiment. The jacketed lap system does not interest me. I will attempt it in my 444 with 400 grit paste rolled into a cast bullet. My 444 has constrictions and is prone to copper fouling. My Win 94 seems reasonably chatter free so I am going to try paper patch in it simply to try paper patching. By the summer I hope to be shooting cast in everything I own except a 223 bolt and a Handi Hornet. That would be 303 Brit, 32 Special, 32-20, and 444.

I have realized that I've never broke in a barrel. I shoot and clean but have never been a guy to worry about a bit of copper. This winter is about getting my rifles clean and copper free or at least close to copper free. I'll use your method above on a new to me 223 CZ527 lefty I bought with a low round count and the Handi Hornet which is shot but not a bunch.

Paper patchers note that PPing often polishes the bore as part of the normal shooting. It seems quite benign.

[oldgerboy]

"Too smooth" might mean polished to the point of having an overlarge bore and resulting in bad accuracy or leading due to the bullet loosing lead due to the bore not sealed from the burning powder heat.

[Paladin]

Here is a copy of (page one of a two page) order that was issued to us to "break in" the then new M-24 sniper systems. I think it makes a difference and when I get a new barrel I follow it.

[3leggedturtle]

Guys, I understand the apparent absurdity to this. However it comes up as possible on some forums.

Didn't mean to come off like a smart aleck but, it did almost make me choke up some coffee on my keyboard. Like some of the others said, I wish I could live long enough to shoot my rifles and pistols to that level of smoothness and see if that is a possibility.