Lube Purging

  • 973 Views
  • Last Post 18 November 2018
frnkeore posted this 19 September 2018

Tell me about it. How and why does it effect accuracy or, is it real, at all?

Frank

Attached Files

Order By: Standard | Newest | Votes
Ken Campbell Iowa posted this 20 September 2018

... i understand that lube purging ... is where the gun shoots fine but after so many shots shoots a wild one or two ( purging excess lube ) ... the shoots fine again until another lube purge is called for ...

"" oh it's purging time again ... yer gonna leave ( the group) ... ""

....can anybody think of an experiment where we could get a better handle on " lube purging" ... ...

as usual, everytime we change something to prove our point, the changes themselves confuse the experiment ...

if we increase the groove volume to hold more grease, the bullet is less supported ...  2000 shots later, we need to then cross check the effect of wide grooves but with less grease .... 2000 more shots ....  then maybe wide grooves with harder lube against softer lubes ... 

we might forever be doomed to johna's * pretty sure *  that lube purges ..... or doesn't purge ...

*************************

maybe we could pre-coat the barrel with more and more lube and see what happens ?? ...  how can even a really really greasy bullet over-lube a barrel ?? .... maybe the waxy grease crystallizes and actually de-conditions/cleans the barrel erratically ....   turning it into a " cold barrel " that needs a fouling shot ( flyer )  ..to return to group center ....

another mystery of cast bullet shooting .  yet another ....

ken

 

Attached Files

Ross Smith posted this 20 September 2018

Why would we cure this? We (I) need some excuse for "flyers".

Attached Files

  • Liked by
  • shastaboat
John Alexander posted this 20 September 2018

I brought up lube purging.  I didn't mean to imply that I believe it is real.  Highest and best use may be as an excuse for those dreaded flyers as Ross suggests.

John

Attached Files

frnkeore posted this 20 September 2018

John,

No I didn't think that. It's something that I've heard of for 10 years but, I don't remember reading anything factual about it. 

I open this to see if there was anything factual or at could be proven, regarding it.

Frank

Attached Files

4060may posted this 21 September 2018

FS 116 and 120, has article about purging

Chuck

Attached Files

Ross Smith posted this 21 September 2018

Why would lube accumulate in the barrel? Doesn't it get "purged" every shot by the gas check if not the driving bands? Something else must be influencing this, rough barrel, leading,//////////?????????????? Just thinking.

Attached Files

4060may posted this 21 September 2018

Merril Martin did a long dissertation on it with 22lr in Precision Shooting, I give away all the Issues I had to a 22lr bench shooter....

Attached Files

frnkeore posted this 21 September 2018

I don't have FS 116 & 120. If someone could read them and give a summery, it would help.

I'm at odds of how it could be documented. Maybe high speed photos?

It seems hard to believe that any kind of lube, could deflect a lead bullet or does the accumulated lube, cause the bullet to ride over it, inside the barrel?

Frank

Attached Files

Larry Gibson posted this 22 September 2018

Some are of the opinion that "lube purging" is the purging (throwing off or spinning off) of the lube out of the lube grooves on exit from the muzzle during flight.  It is believed if the lube purges off the bullet it should do so immediately and evenly otherwise unbalancing of the bullet may occur during flight which, of course, can adversely affect accuracy. Additionally the harder wax lubes may have a "vaning" effect also. 

LMG

Concealment is not cover.........

Attached Files

  • Liked by
  • James Nicholson
Brodie posted this 22 September 2018

And Boys and Girls that is where the "Lube Star" on your muzzle comes from.

B.E.Brickey

Attached Files

fa38 posted this 22 September 2018

I think lube purging was a theory put forth by Tom Gray a number of years ago.  He also experimented with making various lubes and believe the final one was Gray 24.

Attached Files

Larry Gibson posted this 22 September 2018

The subject was also heavily discussed in the HV/RPM threads on the other forum.  The subject was broached when I found a large amount of different lubes being "purged" and ending up on the chronograph screens.  It most was the harder lubes used in older design bullets with large lube capacity grooves.  It was prevalent with both 6.5 and 30 caliber bullets.  The depositing of lube on the screens ended with bullets of better design and the use of softer lubes such as NRA 50/50, 2500+ and the original Javelina.

Here is a photo of the screens I took back then (10 +/- years ago).  Yu can plainly see the lube splattered on the front of the screens.  The little bits and pieces splattered all over all 3 screens indicates the lube is not "purged off the bullets at the same time nor evenly. 

 

LMG

Concealment is not cover.........

Attached Files

frnkeore posted this 22 September 2018

So then, are we saying that lube purging, is simply the normal ejection of lube, when the bullet exits the barrel?

If so, how can it effect accuracy, unless all the lube doesn't leave the grooves?

Is it a misnomer then?

Frank

Attached Files

shastaboat posted this 22 September 2018

Like Old Coot says you know things are right if you have the lube star on your rifle's muzzle.

 

Because I said so!

Attached Files

frnkeore posted this 22 September 2018

The context that I'm speaking of, is that it detracts from accuracy. That is how I hear it referenced.

"a flier, because of lube purging"

 

Frank

Attached Files

Brodie posted this 22 September 2018

Whether or not ejection (through centripetal force) affects accuracy it still makes a mighty fine excuse for what the nut holding the stock caused anyway.

B.E.Brickey

Attached Files

fa38 posted this 23 September 2018

I am assuming that Frank was asking about fliers from too much lube inside the barrel and not the bullet having lube flying off after it leaves the barrel.  Tom Gray wrote about it in a couple of the FS issues.  A couple of photos from FS 116 and 120

 

Attached Files

frnkeore posted this 23 September 2018

Thank you, very much fa38.

He doesn't say how that he proved his purging theory or exactly how it causes fliers. Is there more that explains that? He talks like it's been proved somehow. Or does he just say in the article, that his lube prevents lube purging?

It seems to me that he's talking about the bore condition, being consistent and I would agree with that, if it could be proved that it effects the bullet (damage), velocity (high or low impact) or barrel harmonics but, how has he proved that fliers are a result of to much lube, it seems that, if your considering inconsistent bore condition, being the cause, to little lube, could also be the reason. I would think that to little lube could rectify itself easier than to much.

If the purging, causes a flier, how does to much lube rectify itself, especially with a PB bullet. If a GC scrapes the bore, in the purging, why wouldn't the GC, prevent it, in the first place, when less lube is present?

It's still unclear what it might be.

Frank

Attached Files

fa38 posted this 23 September 2018

Here are the entire articles from FS116 and 120.

Probably have to get your reading glasses for the photos.

 

Attached Files

fa38 posted this 23 September 2018

 

My lube flyer picture of two groups from June 1996. 

Top group was shot with my lube, probably a mixture of bees wax, lanoline, a couple sticks of the 50/50 beeswax and alox, peanut oil and a stick of LBT blue soft for color.  It turns to a light green color.

The bottom was shot with Gray 24.  The two flyers were something like the 5th and 9th shots.  I shot the extra two to see what would happen.  I was going to cut the flyers out and show them to a friend but decided to keep all 12.  The rifle was a Peregrine chambered in a long neck, short body 30 Herrett that I no longer own.

I shot other groups with Gray 24 and decided to quit using it because of the occasional flyers and I could make my lube a lot cheaper than purchasing LBT or Gray 24.  I sold the rest of the Grey 24 to Fred Sinclair.  That does not mean I did not get fliers with my own lube and maybe all my fliers are operator induced.

Ninety percent my shooting at that time was with single shots and plain base bullets at velocities from 1000 to 1500 fps.

Attached Files

Show More Posts
Close