Gentlemen,

Pete Mink has posted me in regard to lube purging.

I have yet to be convinced!

Now, I have heard of and understand that some of the fellows in high/velocity 30 caliber benchrest shooting make a case for purging. I do not know anything about that game and will not opinion about it.

What I'd like to hear about is how supposed purging affects the low speed big caliber shooting such as what I do know something about in the Buffalo Rifle match shooting I do.

Good morning,
Forrest

Jim,

Jim says: First off why do we want to change your mind! I know you need the right amount of lube in black powder loads! to keep the fouling soft!

"BUT" I know it smokeless load You can have to much lube!
A fact!

Forrest responds: OK

Keep in mind that Pete says BP also is subject to this. Since I shoot only smokeless I have some questions:

How do you know if you've "Too much lube"?

If you can determin it, how is it determined how much is the right amount?

How does temperature affect "purging"?

Good afternoon,
Forrest

"Jim and I have talked about this in the past so I'll throw in my 2 cents. We have proved that for smokeless powder at plain based bullet speeds (1200 to 1500) 3 lube grooves is plenty. If you are still getting a lube star at the muzzle and you are not leading its enough lube."

Forty-Rod,

Very well. Thanks for your idea about the estimated amount of lube needed. How did you come up with it?

40:  Where Jim and I part company is when lube purgeing is a factor. My take on purgeing is it happens when the speed of the bullet overtakes the lubes ability to spread out along the bore of the barrel. 

F: I've read that a couple times over. I don't understand the part where you say: "...when the speed of the bullet overtakes the lube's ablility to spread out..."

What do you mean? 

Do you refer to the bullet where the supposed limit of spreading was exceeded and tosses the flyer? 

Or the bullet which encounters the excess lube left over from a previous shot and then tosses the flyer?

This appears quite mysterious to me.

40: This is a product of two factors speed and the hardness of the lube. Softer lubes will spread more easly than hard ones but sooner or later you can push a bullet so fast that the lube will loose its ability to be evenly distributed along the barrel. The faster that you go the harder it is for the lube to coat the bore evenly. When this becomes a factor is the question.

F: Hummm...

I'm unclear here too. Are you saying that hard lubes are more, or less subject to purging?

And! to address the subject as clearly as possible: How can you tell that a given flyer is actually a result of "purging"?

In order to keep things as simple as possible I suggest we restrict the discussion to smokeless loaded plain base bullets in 45 caliber at 1250 - 1300 ft/sec, lubed with the typical soft lube like Javelina, SPG and so forth.

Pete did mention black powder lube purging as well but lets leave that for another possible thread!

Good morning,
Forrest

I hope so,Brent have no idea what may have happied to your first post!
It`s out there in space someplace

I don't know anything about lube purging, but I've read Tom Gray about using less lube, and Harrison's book about using less lube on revolver bullets.
I can shoot 3112992s in a 30/30 Martini without GC or M54 30WCF with or without GC, fixed, with 14.5 IMR4227 or 12.5 AA#9 and lube only the bottom groove and get no more leading than when all grooves are lubed. With a PVC wad and 1 groove lubed, no leading at all. Same 31141, or Hoch bullet in M16 32/35 Maynard, or Ohaus bullet in 45/70..
In the 22, either Eagan 65? gr or NEI 78? gr bullet, no leading with only the space above the GC lubed. (Thanks J. Alexander)
In 44, 429421 with only 1 groove lubed, no leading.
But they don't shoot any better than with all the grooves lubed, and I feel guilty not filling them. Look at the CBA guys with big 30 caliber bullets and 1 grease groove.
I keep trying and hope that accuracy will improve with less lube.
Amazing how little lube is needed.
joe b.

Quote:


I personally have found that Bill's advice is normally dead on the money. When it comes to black, I listen to him first. 'Course, I gotta be willin' to get past the verbal abuse & dogmatic opinions, but I have the greatest regard for his knowledge & willingness to share his expertise.

Now if he would just quit chasin' his last spotted shot.................(VBG)
Regards, Joe

I shoot only black except in .22RF.  Never ever anything else.  So all my comments are with regards to that powder. 

Brent,

Very well. Thanks.

B: The loads I was describing are intended to be shot in a dirty bore, fast and furious for a timed match (25 shots in 10 minutes).  So fouling management is everything.  

F: That sounds like quite the match format ~ the grease-cookie sounds logical for sure.

B: They are also always paper patched bullets which are considerably more sensitive to fouling issues than grooved bullets.  (and hence I would expect them to be more likely to show purging than grooved bullets.  

F: Sure enough. PP shooting is lots different in many ways. If I weren't retired and too busy to patch bullets I'd go back to that technique.

B:  As you know, it is generally far easier to prove something exists than to prove that it does not.  this is one of those instances.  It must, however, be a very small effect if it does exist.  I also fail to see a mechanism for this effect to occur.  Coincidentally yclical systems are hard to construct in general.

F: I'm a smokeless shooter for the main part and the "purging" deal seems to originate with the cast bullet BR boys, especially shooting 30 calibers of some sort.

I virtually never heard of this problem happening in slow-shooting calibers like 32/40 or 45/70 until Pete brought it up in an email exchange.

B: Call it what you will.  I know for a fact that this works.  Took me a whole lotta years and shooting, and one phone call from Bill Bagwell to figure this out.  But shooting dirty bores with black powder and paper patched bullets pretty much requires this sort of loading.

F: Sure. As above the rapid-fire BP match format says it all.

What does "FWIW" mean?

B: FWIW, when shooting targets, and wiping every shot, where time is not a factor, I use a cookie that has only 0.06" -0.09" of lube.  These are the most accurate loads (relative to lesser or greater amounts of lube), and are considerably more accurate than the loads I discussed above.  But they also require wiping after every shot, so purging is a nonfactor.  

F: Back in my PP days, shooting smokeless in a 40/65, I found my best accuracy by 'wiping' each patched bullet lightly with Javelina with my fingers before seating.

Accuracy was excellent, almost worth the additional time required for all the PP procedures. No need for cleaning at all either except when moth-balling the rifle for the winter.

Good morning,
Forrest

Lube purging- for lack of a better terminology- is due to excess lube on the bullet depositing to the bore to...

Singleshot,

Thanks. That helps.

Good morning,
Forrest