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lcg119
03-12-2007, 09:21 PM
Has anyone ever tried using various coatings on the base and/or shoulder of plain base bullets.....to form a sort of gas-check ? I am thinking along the lines of an epoxy-impregnated paint, or heat-ablative paint, sprayed on. Perhaps coating the entire bullet would allow for higher velocities and less (or no) leading. Surely there has been some research done along these lines ?

44man
03-12-2007, 10:38 PM
Forget it. The stuff will just strip off and could be dangerous if any is left in the bore. If there was a magic thing, the casting outfits would have found it after hundreds of years.

JeffinNZ
03-12-2007, 11:13 PM
I am presently pushing a PB boolit at just shy of 1700fps in my .38-303 over 37gr of W748 (100% load density). I am using a .060 card wad under the bullet as in BPCR loading and the accuracy is scary good. Bullet is only 8 BHN.

How fast do you wish to go?

45 2.1
03-13-2007, 06:53 AM
Keep the heat off the base and you can push it very fast. People have done this by: fillers, wads, coatings, freechecks, unburnt slow powder etc.

lcg119
03-13-2007, 02:56 PM
Interesting..... almost 1700 fps with a PB bullet. I am using a medium speed powder, with dacron fibrefill to hold it in place. I also thoroughly lube my (PB) bullets with Liquid Alox, on the base and all bearing surfaces, as well as filling the lube grooves. So, perhaps I will be able to achieve decent velocity...without leading problems.

As 44man said, if there were some magic elixir for this ...someone would have likely already found it.

If it is a matter of keeping the heat away from the bullet base, as the most important issue, then I'd say that I have a good shot at getting useful velocities. Obviously, testing will be the key. I may still attempt to find some sort of coating, for at least the BASE of the bullets, rather than getting into gas-checks. For some reason, I just don't care for that idea.

My newness to CB's as well as my ignorance of this subject area is causing me much worry (perhaps too much) about the issue of leading, based on scrubbing of the bullet as it passes down the bore. I fully understand the gas-cutting issue, as it pertains to the bullet bases. I realize that bullet lube is what is supposed to prevent lead "scrubbing" in the bore....

Maybe I am just worrying too much about it all.


Thanks.

lcg119
03-14-2007, 03:52 PM
Just a small update..... I found some heat-resistant paint, containing silicon....which supposedly will survive up to 1500 degrees F, so I am trying an experiment. I have sprayed the BASES of a number of my PB bullets with this stuff (after degreasing)...the idea being to use it as a substitute gas-check. Copper melts at something like 1200-1300 degrees (F)....so this paint should provide at least as much protection to the bullet bases as a regular gas check. After curing, I have tried to scrape off the paint, to see how well it has adhered....and I can tell you, it is tough stuff. I think that this may well work out as a (simpler, cheaper and easier to use) substitute for copper gas-checks. I have yet to fire any of these bullets, let alone find an acceptable load for my rifle....but I intend to take careful note of the results....and be rather scientific about my testing. I will report on how well (or poorly) this works out, as data becomes available.

Just thought a few of you might be interested.

joatmon
03-14-2007, 04:27 PM
Yes,very interested. New break throughs happen. Please keep us posted.

Nueces
03-14-2007, 09:25 PM
Yeah, me, too. Thanks for the effort.

As you're working out a load, may I suggest a bench experiment that may have value?
Choose a boolit design with a sharp base edge and cast several in linotype, or other relatively low melting temp alloy. Coat the base bands of half the boolits with your paint and set them base up in a row of shallow drilled holes so that coated and uncoated bases alternate. Now, use a torch to apply heat to the bases by running the flame quickly along the row. See if the uncoated edges round over by melting before the coated ones.

Or, tell us what this paint is, and I'll do it. Retirement looms, man, I need to be kept busy!

Mark

lcg119
03-15-2007, 05:06 PM
Nueces,

I am not casting my own bullets - I have no facilities to do this. I am buying them. Right now, I am experimenting with a 170 grn bullet for the .32-40. This may well not work out as a suitable bullet for my 8mm Mauser rifle...but one has to start somewhere. As for your suggested bench test....that is a good idea. I can certainly do a side-by-side comparison test as to the heat ablativeness of the paint, vs. a non-coated bullet...using a propane torch. It perhaps will be a bit difficult to direct the flame to only the BASES of the bullets, but I'm sure that it can be done. I'll try to set this up sometime soon....and report on the results.

PS - The paint I am using is nothing special. It is a metalic grey spray, made by Plasti-Kote, designed for exhaust headers and the like. I found it in an auto parts store.

35remington
03-15-2007, 07:08 PM
lcg, a bit of a tip with dacron or wads and the sticky tumble alox.

You might want to keep the alox off the base of the bullet-you really don't want the dacron/wads sticking to the bullet, as it don't do much for accuracy. With low pressure loads of medium speed powders like you are using, the dacron does indeed survive the trip down the barrel and is not consumed, and often is not even fused, just a dirty gray.

I deliberately tested this with a number of cartridges and weighed, matched bullets. Some fliers did result in the small calibers and light bullets, esp. .22's and .24's-25's. It may be that the larger calibers are not as influenced by this, so if doesn't affect your own results then forget it.

I've had some little success at higher velocities with combining a wad(s) and dacron-the wads/dacron to keep some of the pressure/gascutting away from the bullet, the dacron to keep the wads in place. This only in cartridges where the wads could be contained in the neck of the case. Eventually this proved to be a lot of work and expense for only moderate gains in velocity so I abandoned it, but you never know what you'll wind up with until you try all possibilities.

Sometimes I'll just punt and use a gascheck bullet rather than flogging a plainbase, but it depends upon whether I like the bullet design in plainbase. As an example, I like the RCBS .25 Cowboy flatpoint design so much that I have tried all sorts of unreasonable stuff with it in my .25-20's. Success up to 1550 fps so far, and I'm pretty happy with that. I'd probably have to have a better dimensioned gun to have any success in pushing it faster.

Nueces
03-15-2007, 10:01 PM
Thanks, lcg119, I'll watch for your report.

Mark

lcg119
03-21-2007, 02:55 PM
Well, I had a chance to run an informal, nonscientific test to see whether my spray paint "gas checks" are effective. I used a propane camping stove as the heat source.
I ran the test twice, and thus used a total of 4 bullets. These were commercial hardcast, supposedly approximately 12 on the Brinell hardness scale......323" in diameter and the plain base type...designed for the .32-40 cartridge. Two of the bullets were cleaned of all lube and of course, were not coated with the heat ablative paint. The other two were coated (the bullet bases only) with the heat ablative paint, as well as having been pan lubed with Lee Liquid Alox. There was no lube on the bullet bases.

The major difficulty with this test was figuring out how to hold the bullets in identical fashion, so that a jet of flame was directed at the bullet bases....and not allowed to contact the sides of the bullets. So, I wasted 2 bullets in getting this right, before being comfortable that I had a uniform technique in hand. This involved holding each bullet with a pair of needle-nosed pliers, vertical and centred approximately 1/4" above one of the blue jets of flame issuing from the burner. I was as careful as possible in ensuring that all 4 individual tests were performed as uniformly as possible (hence the wasting of 2 bullets while "perfecting" my technique). The heat was applied until the base of the bullet began to noticeably slump....and the required time for this was gauged, using a stopwatch.

The results were more or less as expected. The painted and lubed bullets stood up to the heat, before slumping, approximately twice as long as the bare ones. The bases of the bare bullets began to slump at approximately 6 - 7 seconds of heating...whereas the painted and lubed ones lasted more on the order of 12-13 seconds. Further, the gas-check paint was not burned away by the flame...but only blistered....and thus remained on the bullet bases. Slumping of the flat base of the treated bullets did not occur at all, during the test. Indeed, the slumping occurred from the lowest part of the bullet side - the bases themselves were relatively unaffected. The plain bullets slumped, beginning at the bases....and continuing up the sides to at least the first lubrication groove. This suggests to me that gas-cutting of these plain-base bullets can be mostly eliminated by applying the heat-ablative paint to the sides of the bullets, up to the first lube groove, as well as the bullet bases. Of course, this would resemble the configuration of a copper gas check.

While this test is by no means completely scientific....and thus, cannot be considered definitive....it does suggest that the heat-ablative paint will make an effective gas-check, in combination with lubing with liquid alox. As I suggested above, the best technique would seem to involve coating the lower portion of the bullet side, up to the first lube groove, as well as the bullet base (thus resembling a regular gas-check). I will certainly re-coat my bullets this way....and I may repeat the test. At this point, however, I am inclined to simply adopt the paint as a good substitute for (copper) gas-checks....and thus use only plain-base bullets. That will save even a bit more money (which I like)...as well as obviate the need for seating and crimping gas checks.

Now to find a good accurate load for my rifle....and get some field data as regards how the bullets stand up in actual- use conditions.

felix
03-21-2007, 03:27 PM
Prolly should shoot those painted boolits in a rougher barrel to take advantage of the silicon within the paint. What I am more worried about is getting the "lube" out of the barrel should it crack and leave behind tough-to-clean areas. But, before you shoot. slick the barrel down with something, and run only one dry patch to take up the puddles. ... felix

Glen
03-21-2007, 03:34 PM
Interesting test, but I disagree with your conclusions. You have only tested heat, and have no idea how this stuff will hold up to abrasion (either barrel friction, or ablation by high speed powder particles), and abrasion resistance is one of the key things a GC contributes to a cast bullet. The answers that really matter here are the actual shooting tests, which I'm looking forward to hearing about.

BluesBear
03-21-2007, 05:47 PM
I am wondering if the spray paint might not work better on gas check design boolits.
The paint would cover the entirte gas check area (it might take more than one coat to achieve proper thickness) and therefore the friction of the paint against the barrel would be minimal. Just as it is with a real metal gas check.

The only trick will be getting enough on the sides of the boolit to prevent flame cutting.

As you described using the paint on the sides up to the grease groove of a plain base boolit, I envision the paint rubbing off, since it will increase the thickness of the boolit. Will this wearing away expose the edges of the boolit and the resulting flame cutting.
And IF the paint chips then you'll have exposed lead also.

In my mind I am seeing a wooden block, five holes in five rows for a total of 25.
Each hole drilled to a tight tolerance for the boolits. Then with the boolit in place with only the gascheck base area exposed you could easily spray enough coats to replicate the gascheck thickness.

I may be wrong but this sounds like it might work.

I am eagerly awaiting the results of further testing by LCG119.
He really might be on to something.

lcg119
03-21-2007, 08:47 PM
You all make good points.

Glen, friction in the barrel, as well as powder particle ablation, could make the idea a no-go. You are correct in that my "conclusion" is probably premature. The friction issue did occur to me...that is why I chose (originally) to paint only the bullet bases. I think that I have a good shot at success with this idea, though...as the paint only must survive for the few milliseconds required for the bullet to exit the barrel - and the bullet lube (alox) should help protect the bullets, as well. Copper gas checks, though more substantial than a couple of coats of paint, are not exactly armour- plated, just as jacketed bullets are not. I am much less concerned about the bullet bases, than I am about the corners, below the first lube groove. Certainly, "field" testing will be the only way to know for sure.

BluesBear, I wondered the same thing. A GC bullet design, with it's rebated shoulder, would seem to offer a place for the paint to adhere, that wouldn't be subject to barrel friction. The next time I order bullets, I may well try to obtain some GC-type....without any gas-checks.

Anyway, I'll see what happens....and report my results. My thanks to all for your suggestions and critiques.

leftiye
03-21-2007, 10:46 PM
How about only painting the bases of the boolits, none on the sides. Stuff might probably chip off anyway. Whole concept will work if the right coating is found. Copper plating anyone? Plastic jackets?

lcg119
04-14-2007, 08:23 PM
Well, I finally had a chance to get in some range time with my "test" bullets....painted with the high-temperature paint I am trying as a substitute gas-check material.

An observation first, about the curing of the paint. The directions indicate that the paint must be baked at approximately 650 degrees F, for one hour, in order to fully cure....and thus, be as durable as possible. This, I found, was perilously close to the slumping temperature of this particular bullet alloy....too close to ensure that the paint can be cured without ruining the bullets. So, after experimentation, I found that using about 450 degrees F, for approximately two hours, seemed to have the same effect (while not ruining the bullets).

As to my results and observations from the range, they are as follows. The bullet lube I am using, Lee Liquid Alox, seems to do the job just fine. Further, there was no apparent problem with the high-temp paint on the sides of the bullets (bearing surfaces)...being deposited in the bore. I tried a number of different loads, 7 in all, varying only by the powder charge (in one grain increments)... loads producing roughly 1000 fps, up to probably about 1500 fps. After 45 rounds...and frequent inspections of the bore along the way, there was no apparent leading problem - nor was there any visual evidence of the HT paint being deposited in the bore at all. Whether this was due mostly to the bullet lube doing it's job....or whether the paint in fact is tough enough to stay on the bullets, I certainly cannot say. I cannot recover any bullets fired at my local range....so I cannot make an examination of fired specimens, unfortunately. I can say that all seemed to go well, as regards the firing of these rounds. There was the typical smoking, from the bullet lube, which did not increase or decrease, regardless of the charge weight. Nothing untoward or strange happened. My rifle developed a nice "lube star" at the muzzle, just as was suggested it should.

Alas, groups (if they could be called that)...were terrible. In other words, there was no useful accuracy at all. Most of the 45 rounds I fired did not end up "on paper". Of course, I do not know whether this is due to the bullet diameter (.323"...a bit small for cast bullets, in a barrel which slugged just over .323").... or the charge weights themselves....or the fact that my M48 has never really liked jacketed 170 grain bullets (so perhaps it doesn't like cast 170 grainers, either). The finished (painted and baked) bullets, before lubing, actually measured between .324" and .325", but I certainly don't know if this made any difference. All I can say, definitively, is that there was no problem with leading or deposition of the HT paint, in the bore...or at least, it didn't seem to negatively affect accuracy.

After I had finished my testing with the cast bullets, I decided to fire about 10 -15 of my favorite light target loads, using jacketed bullets. I wondered if barrel deposits (not apparent to the naked eye....from the cast loads) might have an effect on accuracy with "normal" ammo. The first three or four shots smoked a bit, decreasing each time (I assume as deposited lube was used up in the bore). By the fifth shot, the smoking had stopped altogether. Accuracy, after the first three or four rounds, went right back to "normal" with this load, which is to say, excellent. I had no trouble in placing the last 10-12 shots in a circle 1.5" in diameter, at 50 yards. This is typical for my M48, with this load. So, I have concluded that there was no problem with significant depositing of lead (or the high-temp paint), in the barrel.

Unfortunately, since accuracy was nonexistant, I do not have a good basis on which to draw any further conclusions. I will try a few more loads with these painted bullets, with a bit stiffer charges..and take note of the results. It seems that my particular rifle might not care for these particular bullets...which I doubt will change dramatically, with a bit more powder. Nevertheless, I will perservere and push them a bit faster, to see what effect this might have. I may well try some 200 grain, round-nose, plain-base cast bullets, next. These I can obtain sized to .324", before application of the paint, so they might be a better fit. Also, my M48 seems to like heavier bullets best of all, which is common with Mauser-98 type rifles. I will apply the same regimen with these...namely painting the bases and sides with the high-temp paint...followed by oven curing...and finally, tumble lubing.

I'll keep you posted, in case anyone is still interested.

BluesBear
04-15-2007, 08:51 AM
Interesting. results.

Perhaps a comparison test consisting of firing some of the painted bullets and then some of the same bullet but unpainted using the same powder charge is in order.
That would give us a better idea of the real accuracy.

I'm still interested.
I'm wondering how that paint would work on high velocity handgun bullets?

lcg119
04-15-2007, 03:48 PM
A comparison test (between painted and unpainted bullets) may well be in order. Unfortunately, since accuracy was nonexistant with these particular bullets, in my rifle (so far)....I am not inclined to repeat the testing...at charge weights that do not seem to work for my gun. I will load some hotter charges, perhaps up to roughly 2000 fps, to see if the paint "gas-checks" have any effect, positive or negative. I am inclined to think that these particular bullets will not be accurate in my M48, no matter what I do. It is possible, I suppose, that the painted bullets did not obturate properly at the low velocities (and pressures) at which I fired them....so perhaps more velocity/ pressure will improve this (and thus improve accuracy). The cured paint is pretty tough stuff...and perhaps it prevents obturation at really modest pressures. I cannot say. The bullets are supposed to be about 12 on the hardness scale...so they are not of an unduly hard alloy...so I don't think excessive bullet hardness is an issue. I am not going to expect much accuracy from these bullets, though. Perhaps I shall be pleasantly surprised, who knows ?

As a followup to my observation regarding the APPARENT LACK of barrel leading or deposition of the gas-check paint in the bore....I can now speak of this with more authority. I thoroughly cleaned the bore last night (this was subsequent to my post on this subject yesterday) - and in fact, I found NO evidence of leading or paint deposition at all. The bore was very easy to clean, just as when using jacketed bullets, except that there was no copper fouling (that I could find), as well. So, whether this is due to the Liquid Alox bullet lube....or the gas-check paint...or a combination of both.... ???.... it looks hopeful.

I think that the "acid test" will be to up the velocities (and pressures) with these bullets, until some evidence of leading/ paint deposition DOES occur....and to note the threshold at which this occurs. If I happen to find myself able to push these PLAIN BASE bullets to say, 2000 fps....still without problems (EVEN if accuracy is still not good)....then, I think that this would go a long way to help prove that the "gas-check" paint DOES offer some positive effects. Of course, it would also be very useful to set up a test regimen after which I could recover some or all of the bullets...to examine them closely. If the next batch show any promise at all, I may try to arrange to fire into some sandbags or something similar, so that I might recover fired bullets for examination.

We shall see.

BluesBear
04-16-2007, 06:37 AM
I forgot to ask you how much of the boolit you painted?
Just the base or the entire side?
How about the nose?

If this experiment turns out to be feasible I can envision colour coded boolits.
DIfferent colours for different velocities.

lcg119
04-16-2007, 11:37 AM
For the bullets I have on hand now....I painted the bases and the sides, from the base to the upper end of the bearing bands. I did not paint the bullet noses, or the ogive area....as I saw no reason to do so. I removed the waxy lube from the lube grooves (before painting)....and re-lubed with the Liquid Alox, after the paint was cured, tumble lubing the entire bullet.

jhalcott
04-16-2007, 05:58 PM
Have you considered dropping the bullets into cold water as soon as they come from the oven? This will raise the BHn (surface) quite a bit. What scale are you using to get 12BHN. That is about the hardness of MY wheel weight alloy,air cooled. Linotype is 22 BHN. Are you seeking high velocity or better accuracy.? This seems to be a LOT of work for about 2.5 cents saving per shot.

jhalcott
04-16-2007, 06:01 PM
Have you considered dropping the bullets into cold water as soon as they come from the oven? This will raise the BHn (surface) quite a bit. What scale are you using to get 12BHN. That is about the hardness of MY wheel weight alloy,air cooled. Linotype is 22 BHN. Are you seeking high velocity or better accuracy.? This seems to be a LOT of work for about 2.5 cents saving per shot.I'm JUST lazy, and want aneasy fix!

lcg119
04-17-2007, 11:37 AM
jhalcott,

A very good point, sir. When I originally started this experiment, the intention was so that I could use plain-base bullets....and skip the slight extra expense and bother of gas-checks. Also, I wished to skip having to size the bullets...thus I could skip getting the sizing die/ gas-check crimp tool, as well. The K.I.S.S. principle, you know ? It has turned into a bit more of a headache than I wished it to be. I still do not have an accurate cast load for my rifle, as well. Nevertheless, since I have the bullets in hand, I will carry through with the experiment....and try a bit higher pressures and velocities. I am not expecting any great accuracy from these bullets, but at least I might be able to prove the efficacy of the painted "gas-checks".

Whether I continue experimenting with cast bullets at all, in future, is open to question. I may just drop the whole idea and go back to jacketed bullets.....

PbSnSb
04-18-2007, 05:13 PM
I have a can of Bullet Master Lube from the early 80's.....the company was located in Lake Oswego,Oregon.....there was an article in Handloader about that time. Looking at the label, it's considered an "Air Drying Film Lubricant". It appears to be molybdenum disulphide/antimony oxide using a vehicle of epoxy and polyamid resins....with a substantial quantity of chlorinated solvents.
If I recall the article correctly, significant velocities were reached with this lubricant without leading.

BluesBear
04-18-2007, 09:12 PM
I get better results when using an analgesic decongestant with an antihistamine. [smilie=1:


Seriously, do you have any contact information for them?
I had forgotten about them. I used their lube 20 years ago and really liked it.

leftiye
04-18-2007, 11:11 PM
PbSnSb
Are they by any chance still in business? I have a can of Bullet Master which is dried up. Worked fine back then! Probably better than the new spray lubes. I've posted about this stuff a coulpe of times recently, but probably got the name wrong.

PbSnSb
04-19-2007, 10:32 AM
My first can dried up quickly and they sent me another, if I remember correctly. The one I have now seems to be ok, but I'm not sure that I want to open it until I have an immediate use. The contact information on the can is as follows:
Bullet Master Sales
6182 S.W. Dawn Street
Lake Oswego, Oregon 97034
503-639-8144

BluesBear
04-19-2007, 09:53 PM
Well that telephone number now belongs to Decision Consulting Incorporated in Portland. :(

Next time I go to the Portland Gun Show I'll ask around about them.
Unfortunately I'm going to have to miss the one this weekend but I'll be at the one June 9th.

PbSnSb
04-21-2007, 02:13 PM
Went back and located the article by Al Miller in Handloader #79....from his published test data, you would think that we would all be using Bullet Master by now,i.e., 30/06...Lyman#31141 @ 2714 w/no leading and 1 1/4-1 1/2" groups.....Colt Python using Lyman#356156 @1407 with no GC, no leading and 2 3/4" groups.....he also indicates that it was more effective to size after the lube was applied and that it wasn't necessary to apply the lube full strength.....a mixture as weak as 90% methylene chloride was adequate depending on velocity.

felix
04-21-2007, 02:41 PM
Prolly taken off of the user market? Because of the methylene chloride. That solvent is one of the worst around because it tends to open skin pores and let whatever product pass through. I have seen movies where the bad guys mixed that stuff with snake poison, and then paint steering wheels with the mixture. ... felix

leftiye
04-21-2007, 03:05 PM
Ya know, It does seem possible that nowadays we should be able to come up with a jacket material that could be dipped, or painted on. My first guess would be a plastic or polymer "paint." I mean, how hard could it be to equal paper as shielding for lead? Could maybe use the copper anti fouling paint that they use on boats, or a polymer with a large amount of paint grade copper in it.

Junior1942
04-21-2007, 04:43 PM
If paint will work as gaschecks, I can't understand why aluminum beer cans won't work as gaschecks.

BluesBear
04-21-2007, 11:03 PM
A buddy of mine back in Kentucky had a gizmo that did make gaschecks out of aluminium cans. I think it was called Freecheck and made by Hanned?
They always worked fine in my .41 magnum.
I tried to find one about four years ago but the company seems to have gone out of business.

lcg119
05-12-2007, 09:30 PM
One last post on this subject. I had a chance to go to the range today...and shoot the last of my painted "gas-check" bullets. I tried loads beginning with 26.0 grains (the Yugoslav milsurp 8mm powder)....up to 31.0 grains, in 1 grain increments - starting from where I stopped before. None of the loads were accurate through my rifle, which I expected to be the case (the bullets, at .323" before painting, are simply too small). However, there is no sign of leading or deposition of the gas-check paint in the bore. Cleaning the bore was a breeze, just as after the previous test (with lighter loads). I am guesstimating that, based on previous loads, etc., that at a maximum (31.0 grains)....I was pushing the bullets at perhaps 1700 - 1800 fps. So, it seems possible that, in this case, the gas-check paint was at least effective at staying on the bullets in the barrel. Perhaps the lack of deposits only means that the bullet lube (Lee Liquid Alox) was doing it's job. Perhaps the painted gas-checks are fully effective....I cannot say. It would have been nice to see some moderate accuracy from at least one of these loads...but, alas, that was not the case. I am not able to recover bullets fired at my local range, so I cannot do a definitive examination of a fired bullet, to really gauge the relative efficacy of the gas-check paint.

I'm not sure where I will go from here....I will likely try some bullets sized at least .324" in diameter. Probably something in the 175 to 200 grain range...with gas-checks already installed. I found a source for some 175 grainers that fit these criteria, for approx. $ .12 each shipped....but I am not certain that this includes the gas-checks (I'll have to ask directly, to be sure - IF this price does include gas-checks already installed, then I think it will be well worth trying these). Frankly I am not as enthusiastic about cast bullets as I was in the beginning....as it seems a bit much to deal with all of the related issues, in order to save a few dollars on projectiles. I am not encouraged by the idea of paying a (net) cost of $ .15 to .20 each for sized, lubed, gas-checked bullets....when I can shoot jacketed ones for $ .21 to .28 each (net), with no bullet prep required. I will probably try another 100 of a (seemingly) more suitable cast bullet, just for the sake of "science"...but after that, who knows (especially if I get poor accuracy). I have heard that it is often much tougher to find a good cast bullet load, than it is with jacketed bullets.....so I probably should not be at all discouraged (after all, I really haven't yet scratched the surface of this area).

The older I get, though, the simpler I like things to be - so I am always conflicted about matters such as these.

leftiye
05-12-2007, 10:30 PM
Lcg119, I was glad to see a further post on this thread. At first glance one is sceptical about painting boolits. But then you think about it and it's not only "why not?", but it seems very probable that anything that will adhere strongly enough not to come off of the boolit will probably work. Semi flexible plastics mught be real good. I don't think heat is nearly the problem usually thought, I think that all it has to do is stay on the boolit, and not do damage. As long as it separates lead from steel, it"s all over.. If it contains dry lubricants so much the better. Anybody got any ideas?

BluesBear
05-13-2007, 05:20 AM
I recall, back in the good ol' Pangor Punta days, when S&W announced Nyclad ammunition. (They directed it towards lowering lead emissions in indoor ranges.)
Everyone guffawed at the idea of a plastic coated bullet.

No one's laughing today.
Turns out it was good at more than just reducing toxins.

It long survived the demise of S&W's ammunition division.
Federal quickly bought the rights to produce it and a lot of people still swear by it.
Some folks even say it was Federal's vision to buy the rights to Nyclad and Scorpion bullets that enabled Federal to become the major ammunition company it is today.

People have embraced firearms with spray on finishes. So why not boolits?

leftiye
05-13-2007, 04:23 PM
Anybody have knowledge of a polymer paint that would stay put on the boolit, and also take the heat for a moment? Maybe one that you could mix MDS into.

leftiye
05-15-2007, 11:45 PM
Any one have any idea as to how the "Nyclad" boolit coatings are applied, or what they might be made of?

Newtire
05-17-2007, 08:38 AM
Maybe I am just off on the wrong track or not but I always have heard that the gas check's purpose was not to prevent the boolit base from melting but to keep the bases uniformly flat under the pressure of firing or something along those lines.

I read where the short trip down the barrel of even a long barreled Mosin Nagant (for instance) and the time involved wasn't enough to heat the boolit base up to cause any actual melting.

It said (wherever I read this?) that the flat surface of the check helped to give a more uniform platform for the pressure to have a chance to make the boolit obturate and seal the bore.

So, this is not straight from the burning bush on top of Mt. Galena but seems more logical than the heat theory. Just a thought.

BluesBear
05-17-2007, 05:04 PM
It's not so much that the lead actually melts, because it doesn't. Examination of recoverd fired boolits will confirm that. If the boolit had actually melted the base would become a glob.

What the gas check really does, is attempt to prevent erosion of the base by the hot, high pressure gases pressing against it.
Like any high pressure gas, the gasses from burning gunpowder are looking for an escape route.

The gas check actually deters obturation of the boolit.
This makes proper sizing of a gas check boolit every bit as critical as a plain base one.

maximus
12-09-2010, 02:49 PM
I was thinking on EZ-SLIDE ALKYD GRAPHITE COATING since graphite melting point (3700 or 4000 K), it may work , i dunno test it in 9mm first lol then go up!

leftiye
12-09-2010, 10:57 PM
No, the lead doesn't melt. But I think it gets a lot softer. Virtually all deformation that causes inaccuracy could (can) be caused by "soft" lead - maybe caused by heat. Look at how paper patching changes the situation!

maximus
12-10-2010, 04:50 PM
i have tryed graphite oil, it worked fine, but very mokey.

Jim
12-19-2010, 02:52 AM
In the beginning of this thread, it was mentioned that keeping the heat off the base of the bullet is the trick.
Back in the spring, there was a thread going on(for a looong time) about shooting boolits at some incredible speed like warp 9. The poster wrote that he used plastic shot shell buffer over the powder to create a barrier between the powder and the boolit and it also created a false 100 percent case density.