Author Topic: Lead Bullet Melting in .45 Colt  (Read 2161 times)

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Offline azvaquero

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Lead Bullet Melting in .45 Colt
« on: October 31, 2005, 11:21:30 AM »
Hi Veral --

I am shooting 255 gr. 10 BHN BB Air Cooled WW in .45 Colt Vaquero, over 7.5 to 9.5 gr. Unique.  Throats measure .4525.  I have tried .452 (slip fit) and .453 (drive through with mallet only).  Vaquero has been firelapped.

The problem I am having is that I am getting leading not only in the throats, but back around and behind the mouth of the brass and on the leade (angle portion between chambers and throats).  Of course, the barrel is leading also (it has a smeared appearance, as if the lube has been blown off the bullet and it is rubbing on by friction).

Am I correct in assuming that the leading around the mouth of the brass and in the leade is from the melting base?  I cannot see how friction would cause this as there is no contact between the bullet and the areas mentioned.  The leading around the mouth of the brass actually reaches back down the sides of the brass, maybe .100" or more.  It has to be blown back there, not because of friction.  I have noticed this from time to time in other guns, but all my .45 Colts seem to have this problem.

My questions are these: 1) What is causing this leading; and 2) What can I do to remedy the problem?

I think once I solve the leading problem in the cylinder itself, the leading in the barrel will probably be gone too.  I have the same problem when using Titegroup, and also when using 15 - 16 BHN bullets.  Can't figure out what to do.  Any help will be greatly appreciated, and thank you for your time.

Offline Lloyd Smale

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Lead Bullet Melting in .45 Colt
« Reply #1 on: November 06, 2005, 12:44:05 AM »
not veral but if you want an opionion what i would look at is if your cylinder is lined up with your bore. Id guess not. Id say by the sounds of it that your bullets are shaving lead when they hit the forcing cone. It may be a simple matter of sending it back to ruger to check alingment or just recuting your forcing cone.
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Offline azvaquero

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Lead Bullet Melting in .45 Colt
« Reply #2 on: November 06, 2005, 05:41:40 PM »
Thanks Lloyd but that's not it.  The leading I am talking about is happening back in the throats, leade, and even back around the mouth of the brass.  In other words, the leading occurs before the bullet even gets to the forcing cone or the barrel.  If I had no leading up to the forcing cone but did have thereafter, then I would look to problems in alignment, barrel, etc.  But when leading is occuring on the leade itself, that is another issue.  Thanks for the thought though!

Offline Lloyd Smale

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« Reply #3 on: November 07, 2005, 12:11:24 AM »
ive seen it happen where a gun that was out of align would actually shave lead when hitting the forcing cone and that lead would end up on the brass and in the chambers like your experiencing. I also experinced the same thing in my 500 linebaugh until i found that my bullet sizing die was out of round which was causing the shaving in the forcing cone.
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Offline Lone Star

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Lead Bullet Melting in .45 Colt
« Reply #4 on: November 07, 2005, 04:58:19 AM »
You are experiencing gas cutting of the bullets, most likely due to too hard of a bullet alloy for the pressure of your loads.   Unique powder can be particularly bad in this respect.  The gas cutting is liquifying the alloy and it is then carried anywhere the gas moves, where it then plates out.

Many years ago I experienced a similar situation with quenched WW alloy in my .45LC BH.  I loaded up 25 rounds in five different charge weights of Unique, from 8.0 to 10.0 grains in half-grain steps.  Firing at targets the first groups were widely dispersed and the barrel was leaded.  By the time I got to 10 grains the leading was virtually gone and the group size was quite tight.  The pressure had finally reached the point where the hard bullets were obturating enough to seal off any gas cutting.

When I first started to reload for the .45LC (in the early 1970s) I used quenched WW alloy.  I would often dig the fired bulets out of the backstops and observe that the rear bands were badly gas cut, but I didn't know enough to diagnose the problem.  Once I performed the above test I learned that I needed either softer alloy or more pressure to eliminate leading.  Since then the Cast Bullet Association published their findings that most leading is due to gas cutting, not friction or rough bores.  It all makes sense now.

Your solution will likely be to use a softer alloy or more powder/different powder.  Also check to see if your bore diameter at the forcing cone is larger than your cylinder throats; this can cause the same problem once the bullet enters the bore and the gas can get around it due to the large bore.

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Offline azvaquero

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Lead Bullet Melting in .45 Colt
« Reply #5 on: November 09, 2005, 07:01:44 AM »
Thanks Lloyd and Lone Star.

Lloyd, I guess that could be happening, but I still question it because this is happening in all my .45 Colts.  I have 2 Vaqueros (one out of box, the other firelapped), a SRH (this one has big .454 throats, so I can understand how this would lead without my using a large bullet).  The other is a Blackhawk, with a cylinder that was reamed from a .44 mag cylinder by Dave Clements (this he linebored).  All of these lead, all in the throats, so my guess is it has something to do with the load instead of the gun.  But that is interesting that lead was blowing backwards, I guess that is entirely possible because of the tremendous pressures involved.

Lone Star, thanks for the comments.  Your thoughts were my thoughts, and here's what I have tried:

Initially, I was using Meister Bullets .452" RNFP (produced from a Magma mould), and coming in at about 15 to 16 BHN (measured with Veral's hardness tester).  Meister uses a 6/2 alloy (92% lead, 6% antimony, and 2% tin -- or was that the other way around?)  Leading was pretty bad.

I also cast some of my own and played around with sizing diameters with the same type of alloy.  My bullets were again about 16 BHN.  Leading was bad.

I then tried WW's, without water dropping them.  I too believed that the BHN was too high, and that was causing my problem.  My air-cooled WW bullets come in at around 10-11 BHN.

I continued to get leading, heavy in the forcing cone, and very little in the barrel.  Don't remember if there was any in the throats, but my guess is, probably yes.  There was a restriction in the barrel at the threads, so I firelapped.  Now the leading pattern has changed.  The leading in the throats appears sprayed on, as if by a hot torch (just as you allude), and the leading in the barrel now comes out easier, there is less of it, but it extends the full length of the barrel.  Kind of has a smeared-on appearance.  My guess is the same as yours -- I am getting gas cutting back in the throats, which is blowing off all or nearly all the lube, and the unprotected bullet skids down the barrel dry.

So my next move was to try increasing pressure on that 10 BHN bullet, to obturate in in the throats.  I like to shoot 7.5 gr. Unique (the bullet being 250 gr.), and this I increased in increments up to about 9.5 gr.  I was surprised that leading did not seem to decrease, esp. since the bullet is relatively soft.  Maybe I need to try 10 gr. Unique?  Also, I will try maybe some 2400 to see what happens.  Maybe 13.0 gr. Blue Dot.

These bullets are bevel based.  It seems to me that pressure is pressure, and that the bullet would seal even with this "boat tail" base, but maybe this is a contributing factor.  Maybe I should try some plain base bullets.

Please let me know if any of you have any other thoughts, and thanks to all for your comments.  Would enjoy hearing your opinion, Veral.  Thanks

Offline Castaway

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Lead Bullet Melting in .45 Colt
« Reply #6 on: November 09, 2005, 07:44:37 AM »
Odds are that the problem is being caused by the bevel based bullet.  In my opinion, they are the cause of cast bullets bad reputation.  Bevel based bullets and hard cast have been sold as easier to seat and harder must be better (for some unknown reason)  by the commercial casters.  Bevel based bullets drop easier from the gang moulds and hard bullets have fewer culls.  Fewer hangups and fewer culls means more product in a faster time, not a better product.  You're on your way by casting, but the first thing I'd do would be to fix that mould to a flat base or get a new one.

Offline azvaquero

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Lead Bullet Melting in .45 Colt
« Reply #7 on: November 09, 2005, 01:31:04 PM »
Thanks Castaway.  I have the RCBS 250 GR. RNFP flat base, I'll give that one a try when I have time to cast some up at 10 BHN.  Veral recommends BB bullets in his book, over plain base, which made me suppose that there weren't problems.  I figured Veral had tried them all.  

Just wondering if anyone else out there has ever tried BB bullets successfully, with no leading.  Veral?

Offline Veral

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« Reply #8 on: November 09, 2005, 03:28:43 PM »
I'm going to leave all the above discussion in place, even though I don't agree with all of it.
  First of importance:  If either lead, and or smoke, is coming back on the outside of the cases, pressures are too low to slap the brass out against the chamber and provide a tight seal, and bump the bullet base up tight against the swollen brass.  Don't try light loads of slower powders to stop this.  Up the loads with the powders you have until the cases come out clean.  You might also try magnum primers if you are shooting in cold weather, which it is right now in some of the US.  The Colt brass is roomy for such light charges and a little more fire may get pressures up before the bullet starts moving.  If powder gasses are blowing past the bullet while still in the case, as you seem to be experiancing, the lube, or wax used for lube, is wiped off the bullet before it gets to where friction reduction is required.
  Gas Cutting:  I've read a lot of ink on this subject and most of the theories I've disproven.  If bullets are too hard to obturate and seal whatever part of the they are passing through, it is possible for gas cutting to go the length of the bullet alongside the non driving side of the rifling lands, and possibly between the bullet body and bottom of the grooves.  It doesn't take much upset of the base to create a seal against the latter problem, but lack of adaquate lubrication can cause the leading edge of the rifling to peel lead, opening a gap on the non driving side, for blowby.  Rough rifling EDGES can cause the same problem, but your lapped bores won't have that concern.   The second area of so called gas cutting in all the way around the last edge of the bottom driving band, which will show roughness and appear to be somewhat torn, melted or burned, as you prefer.  It is caused by friction melting the lead at this point which is obturated most tightly against the bore, and a higher quality lube will fix this problem instantly, without changing powder charge.  Even a slight smear of LBT Blue soft, wiped over the wax which many commercial casters call lube, will be enough to solve the problem.  If this latter problem occures, the lead will be deposited mostly in the grooves, and heaviest close to the throat.
Veral Smith

Offline azvaquero

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Lead Bullet Melting in .45 Colt
« Reply #9 on: November 10, 2005, 07:09:08 AM »
Thanks Veral.  What, in your opinion, would cause lead around the upper 1/32" to 1/8" of the brass, on the outside?  I think you are absolutely right about the brass not sealing tightly enough when this is happening.  However, I am at a loss to explain how friction could cause this lead around the mouth of the brass.

Also, what is your opinion on BB bullets, as far as gas cutting is concerned?  Do you believe BB bullets allow gas cutting more easily than a PB bullet, as has been discussed above?

A Thought on Bullet Expansion: Conventional thought (Elmer Keith) used to be that bullets should be sized to fit groove diameter.  Now most authorities realize that throat diameter is more appropriate.  A properly obturating bullet must expand to fill the throat, which is then sized down inside the barrel to groove diameter.  The more a bullet is sized up and down, back and forth, the more it is thrown out of balance.  Less is more, in this instance.  HOWEVER, from what I am seeing here, the bullet must obturate BEFORE IT EVER LEAVES THE CASE.  Otherwise, the lube has already been blown away.  If this is the case, should the lead bullet not be sized to chamber diameter minus the wall thickness of the brass?  Why size it to throat diameter, if it must first expand to fill the chambers themselves, only to be sized back down by the throat, then again in the barrel?  Any thoughts or experience on this Veral?

Offline Veral

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« Reply #10 on: November 13, 2005, 05:51:20 AM »
I certainly have plenty of thoughts, and you have addressed all the issues quite well with your questions.  Bear in mind that it is too easy for me to discuss problems relitive to my own bullet design features and leave readers in the dark so far as other designs, as I have you.

  First, bevel base:  I realized a few hours after writing my above comments about them that my answer was misleading, mostly because I cut very tiny BB's in my molds, which leaves performance so far as base obturation very close to what a flat base gives, though my tiny BB's DO increase pressure requirements for obturation.  Other moldmakers, and particularly Magma, cut very large BB's, closer to a boat tail, which create serious base obturation problems with light loads if the bullets don't fit the gun on takeoff, demanding MUCH higher pressures than a flat base for obturation.

Hold all this is your mind as I discuss bullet fit.  Again, my bullet designs differ dramatically from all other mold makers in that if possible I put a wide driving band outside the case, EXTREMElY wide on my WFN's when the nose is .4 inch long.  This band MUST be sized for a slip fit into the throats or ammo WILL NOT CHAMBER.  In other words, this close fit is a tight enough seal that minimal blowby can get around it, thus obturation of the heel isn't necessary to prevent the problems you are experiancing.  

Pretty much all bullet designs offered by other mold makers, and especially those designed for commercial casters, as Magma molds are, have an under diameter, or at least very short driving band outside the case to insure chambering in all guns.  Furthermore, most commercial caster size to nominal diameter or perhaps .001 over.  Bingo.  The problems you have arise.  If you were concentrating on obtaining the highest possible velocity from bullets so set up, the large bevel base is an asset in allowing higher velocity levels before leading occurs.  However with your light loads you probably are getting no obturation at all at the heel.  The bullets lead till the cylinder throat walls catch them and gas rips the lube off on takeoff, while THE HIGH HEAT OF ESCAPING GASES causes the gas cutting you are experiancing.  Get that straight.  If gases are escaping lead doesn't melt from aroung the heal.  Period.  Also the leaning bullets cannot be straightened out in the barrel, but fly through cattywhompus, and hit the target with even more lean.  In other words, a close fit prevents bullet tipping, and insures top accuracy.

If you have a lot of the commercial cast bullets left, or if you want to use commercial cast for whatever reason, the dead sure solution for preventing leading is to add shot buffer over the powder.  Use enough to get some compression.  It is available where ever shot shell reloading supplies are sold.  Upon firing it forms a hard plastic wad behind the bullet, which wipes any leading away and totally eliminates all blowby.  If the bullets aren't a precise fit to the gun, accuracy cannot be equal to bullets which fit properly, but accuracy will be consistent, and as good as possible with the loose bullets, with zero leading.
Veral Smith

Offline West Creek Charlie

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Lead Bullet Melting in .45 Colt
« Reply #11 on: November 16, 2005, 11:10:53 AM »
I'll never claim to be nearly as educated as some of these guys but I do shoot mostly 45 colt and experienced much of the all the same problems you are experiencing. I got a 250 WFN from veral and lube with Felix lube and all those problems went away with a big increase in accuracy. I shoot 5.6 grains of red dot or 7.2 grains of 231 for a little over 800 fps and get NO leading. Guns are much easier to clean and require it less often as well. From my experience I can easily say that a flat based bullet with a good lube will most likely solve your problems. It even works for me if I use other bullet designs as long as they are flat base and cast with air cooled wheel weights.

My only problem now is getting enough vel to get the WFN to shoot straight at longer ranges out of my SAA's. My 231 load works better than the red dot load. I think the key there is more velocity.
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Offline azvaquero

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Lead Bullet Melting in .45 Colt
« Reply #12 on: November 16, 2005, 03:43:01 PM »
Thanks Veral, West Creek, and all.  Thanks West Creek for telling me your experience with the LBT WFN 250 gr., that answers a lot of questions.  

Well, anyway, I'm fit to be tied.  I have gone out over the past couple of days and shot some 255 gr. Lyman 452424 (Keith style SWC, flat base), air cooled WW, 10-11 BHN, and am still getting leading.  I started out with 8.5 gr. Unique, with leading, then went to 9.5 gr., with maybe a little less leading but still there.  The grease groove on this bullet is much bigger than the Magma RNFP I was shooting (which has a tiny grease groove).  I have a bunch of Ballisticast lube that I am using up, which is what I have been using.  The other lube I have used in the past is Magma lube, which is crayon hard.  The Ballisticast is slightly sticky at room temperature -- seems to be better lube than the Magma -- so I have been using it.  The 9.5 gr. loads really throws my Vaquero up in the air with some good force, so I can't hardly imagine that THIS is not enough pressure!  Maybe if I were shooting Lynotype, sure, but not Air Cooled WW.  Leading doesn't seem quite as severe as when shooting the BB Magma RNFP, but it is still there.

I don't think it's much of a lube issue.  Once again, the leading is most severe back in the cylinder throats.  This lead absolutely sticks like solder, and it looks like it was blown on with a hot torch.  Very difficult to remove.  The leading up at the muzzle has a smeared, flaky appearance, and comes off no problem at all.  The lead in between (back towards the breach of the barrel) is somewhere in between these two extremes.

As I said, then, the quality of the lube doesn't seem to be the issue back in the throats, because gas appears to be just blowing it away before it has a chance to go to work.  The smeary lead at the muzzle most certainly is a lube issue (lack of it, that is), but if I get the throat problem figured out my guess is that the rest will work itself out.

It seems that maybe the bullet design is the culprit.  Veral, I am wondering about something you said.  The Front driving band on the Lyman bullet is only about .060" wide (measured fairly inaccurately with my micrometer, which I couldn't get hooked around the edges of the band very well).  I am wondering if too much gas is blowing past the significant gap between the front of the front band, and the throat.  There must be at least a .050" gap there (i.e., I measured my cylinder previously, and it will take a .110" front driving band, this before firelapping, so it could be more now).  Maybe, if this gap is minimized, the pressure will still be there on and around the base and middle bands, and lube groove too, but it won't be moving past the bullet in such volume and maybe won't take lead and lube with it as it blows.

Could I try seating the bullet out about .050"?  I wouldn't be able to crimp into the grease groove, but I could apply a taper crimp of sorts.  Would this be worthwhile to try, just to see if having a wider front band would help?

I am saving up for a mould from Veral, but I would like to figure this out before then, and hopefully get some of my other many moulds working as it would be a shame to be able to use none of them.  Also, must be many other people that have been able to get these other designs to work somewhat well, without leading, as they have been around for years and many people have reported favorably on them.  This is more of an issue for me at this point of a problem that I must solve -- it bugs me and I will not sleep until I can figure out what is going on.

Anyone else have experience similar to me and West Creek?  Veral, do you think the front band is the problem?  Thanks to all.

Offline Veral

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« Reply #13 on: November 21, 2005, 05:36:29 PM »
Hoboy!  You sound like exactly the same kind of nut that started LBT.  -- The reason I got so deep into cast bullets was because of leading problems with my first molds.  I couldn't sleep either till I found the solutions.

By all means seat some bullets out and see what happens.  If the bullet diameter is a close fit to the throats, seat them out till you KNOW the front band is out where it fits close, and don't even bother to crimp.  Just load up a dozen and single load them, so the uncrimped bullets don't move.  If the cases show now more lead, you have one answer.  If there is no lead anywhere, you have all the answers and your lube is adaquate for the speeds of interest.  However, I do believe you lube isn't good enough to prevent barrel leading, and if it isn't, try some from LBT.  It stops a lot of headaches of the type you have.
Veral Smith

Offline unclenick

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Lead Bullet Melting in .45 Colt
« Reply #14 on: November 23, 2005, 11:43:18 AM »
This is an interesting and educational discussion.  The fact lead is on the outside of your case mouths says the case isn't swollen to chamber diameter while the bullet is still on its way out of the cylinder.  Thus you get gas cutting that blows back into the chamber around the case.  The BB will exacerbate this problem because it starts letting gas out of the case mouth earlier in its travel.

I like Veral's suggestion of the shot buffer.  Another thing to try is cutting a short stack of wads from shirt cardboard or from LDPE sheet using a sharpened case.  This is miserably slow work, but as a diagnostic tool may be worthwhile.  You could also buy .45 caliber P-wads from NECO and use 2 or 3.  The idea is to get a gas seal that keeps the case inflated until after the bullet has got a little further on its way.

Another experiment, now that you've fired some heavier loads and have fire-formed cases, is to decap manually or with a Lee universal decapper die, then size only the first quarter inch or so below the case mouth.  This leaves the rest of the case fat and reduces the amount of pressure needed to keep it sealed against the chamber walls.

In the end, I expect you will want one of Veral's long driving band bullets with a nearly flat base.  Good luck and keep reporting results!

Nick

Offline Veral

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« Reply #15 on: December 04, 2005, 07:25:21 PM »
Since writing the above answers I thought of a way to proove whether BB bullets are causing such a problem.  Use a coars file and fill the bases till the bevel is gone.  You won't get them square enough to give good accuracy, but if the sharp edges stop the leading you know what the problem is.

  Don't expect wax wads to stop the gas flow past the bullet.  It isn't tough enough, as we are dealing with some pretty sharp pressures even with light loads where this type problems shows itself.

  For your information:  Peak pressures in revolvers happens before the bullet leaves the case completely, especailly with the faster powders.  If the bullet doesn't obturate inside the case, it isn't going to, in which case our gas seal has to happen up front between forward driving band and cylinder throat, or with some sort of firm wad behind the bullet.

  Also, please read the post about crimp jumping.
Veral Smith

Offline azvaquero

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Lead Bullet Melting in .45 Colt
« Reply #16 on: January 17, 2006, 04:51:28 PM »
I was sitting in front of my computer reading the latest edition of Handloader, and decided to check my old post to see if any new replies had come in.  Veral, I hadn't seen your last reply until now, so thanks for the information, which I will definitely try (filing the bevel base, that is).  The bullet is Magma's 250gr. RNFP, which has a very SLIGHT bevel base (not much at all), which should be easy to file off.  I have some Lyman 255 gr. SWC's with a flat base that I have loaded up and will go out and try.  I haven't had much time for experimentation but I have had a little and have learned something each time.

Number one, I got the Magma bullet to stop leading in the cylinder throats when firing them with about 10 grains or so of Unique.  I could not have imagined that it could take so much pressure to stop the leading, but it did.  The barrel still leaded, but it was plainly visible that this was smeared on lead, caused by lube inadequacy.  I want to get problem number one fixed (cylinder throat leading) before I even begin to worry about number 2 problem (barrel leading -- which I suspect will be easier to fix).

One thing I am convinced of, though, at this point, is that there are two culprits involved here with leading.  One is friction, as you state in your literature, Veral.  However, I am now more convinced than ever that lead melting/lead spray is involved.  Veral, you call this gas cutting, but is this not one and the same thing?  If gas cutting is not actual melting but the blowing off of microscopic pieces of solid lead, the effect is the same.  Anyway, the two types of leading I described above have a totally different appearance, under a microscope (I use a good one which I have access to -- a Meiji EMZ stereo, which probably retails for around $2,000.00).  The leading in the cylinder throats has a sprayed on, melted appearance, and is extremely difficult to remove.  Under microscopic inspection, the LEADES (the short, angled, tapered portion between each chamber and each throat) has lead spray appearance.  The barrel leading on the other hand appears flaky, smeared.  That has to do with lube failure.  

To further support my belief that actual melting is going on, I have examined recovered bullets around the base perimeter.  There, I find unmistakable signs of melting/gas cutting.  I'm not talking about the uneven, melted appearance of the base viewed with the naked eye.  What I am talking about are microscopic rivulets visible only under the magnification.  There are rivulets (not always, but occasionally) around the lee side (non driving side) of the rifling grooves where gas tends to cut, which run comparatively deep (5 to 10 times as deep as the rifling grooves), where no friction against metal could possibly take place, as they are too deep, and it appears like a ditch bank washed out by water.  I don't think these would be visible under a magnifying glass, but they definitely are under a good microscope.

In further evidence of this, at low pressure, where the case doesn't seal up against the chamber walls very well, there are flat lead deposits around the top perimeter of the brass (along with black soot).  This was discussed above.  How else could the lead get there?  Gas cutting is melting lead (or blowing microscopic pieces, whichever you will), and blowing it backwards.  This lead is then smashed between the expanding case and the chamber wall.  This cannot be cause by friction, however the case may be, as the bullet at no times comes in contact with that portion of the chamber.

The above lead me to the unmistakable conclusion that there is more involved in leading than friction alone.

I truly think Veral has stated the solution, however: a full, tight front driving band.  I measured my cylinder throats since leaving the above posts (remember, they were firelapped) and they are now about .454 back towards the leade (right in front of the bullet), tapering to about .453 up towards the exit point.  It appears that if a good seal is maintained up front, between the front portion of the bullet and the throat, this may benefit nearly as much as an obturating base in deterring leading.  That is, if gas pressure passes up around the sides of the bullet but cannot blow by the front band, it cannot easily carry anything with it as it has nowhere to go, and pressure builds much more rapidly back inside the case, causing it to expand and further seal gasses.  Obturation then takes place much more quickly.  If gasses on the other hand are allowed to leak out past the front of the bullet, pressure cannot be built nearly as rapidly and lube and lead are carried away, and obturation is much more difficult to obtain.  Case seal is more difficult to obtain.  Veral has addressed this problem with a full diameter front driving band.  Nobody else seems to have figured that one out.  There are a lot of "fake" LBT style bullets out there that have an undersized front driving band, which gives up much of the performance of the real thing.  All they have is the wide Meplat, but no front driving band to speak of.

I think that the fact that I have had a .454 space at the beginning of my throats, with a Magma bullet with a smallish front driving band, has caused much of my problem.  I will, then, keep experimenting and trying different things, and posting my results.

I think we all owe untold credit to Veral Smith, however.  In the area of bullet design, it would by no means be a stretch to call him today's Elmer Keith.  Certainly his contributions in this area have been just as original, just as revolutionary (if not more so, which is probably closer to the truth), and just as timeless.  His designs are still considered to be the last word in heavy handgun hunting.  I think we are all fortunate to be able to communicate with this man, via this forum, while he is still around.

Offline Veral

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Lead Bullet Melting in .45 Colt
« Reply #17 on: January 21, 2006, 07:08:16 AM »
Your explaination of gas cutting, being deep on the non driving side of the rifleing is common but as erronous as going to a junkyard and looking at wrecked cars, then trying to determine what caused the damage.  The cause in this case is because the driver didn't prevent the impact.

  Blowby gas cutting on the non driving side of the lands happens long after the driving side of the rifling has filed, abraded, melted due to friction (poor lube) or whatever, a bit of lead off the bullet, which in turn opens a gap on the non driving side of the land, which allows blowby, which releases the hydrolic lube pressure required for optimum lubrication and also blows out any lube touched by the hot gases, long before any lead is warmed to the melting point.  The lack of hydrolic lube pressure causes faster abrasion on the rifling driving side, a larger gap, etc, etc.  

  The only solutions for gas blowby that I'm aware of are a smoother bore finish, higher quality lube, sometimes a harder alloy, and gas checks, not necessarily in that order, but in the order of importance dictated my the conditions of barrel, bullet, lube etc.

  It makes me feel REAL good to be compared to Elmer, on any grounds.  He was my idol starting in my teens.  But to set the record straight.  If Elmer at his best and I at my best were to get into a shootout, he'd have shredded me to fairly decent gunpowder.  If we went head to head on technology the reverse would be true, and he is still my idol.  He had hunting conditions we today can only dream of.  I've had years mechanical knowledge and experiance Elmer couldn't comprehend even existing.  In fact much of what I've learned mechanically wasn't possible to learn during Elmers learning years, even in machine shops, and for sure off a wonderful saddle horse.  (I love horses as much as he did, but it isn't likely anyone would consider me as good a rider!)

  I guess what I'm saying is. Elmer and I have both given our best with what we've had to offer, which doesn't make either persons accomplishments superior to the other when viewed overall.  Nor either of us superior to anyone else who has given their best in their chosen field.  I love small enterprising USA.
Veral Smith