Polyurethane anyone?

[shooting on a shoestring]

I just got back from the range with my nephew. We collectively emptied about 1600 cases, 38s and .357s. I was pleased with the Lee 158 TL SWC and the standard Lee Alox lube in .38. As I plan the menu for reloading, I thought I'd revisit Johnson's Paste Wax. Then I thought about using polyurethane. We have wood floors in my house and touch up a few spots with polyurethane. The first time I tried JPW, I had a problem with JPW flaking off the boolits in loading, and thought polyurethane might bond to WW boolits better than JPW. At .38 pressures and velocities, polyurethane just might be sufficient as a boolit coating. Has anyone tried it? Have any thoughts? I'm thinking of tumble lubing about 100 Lee 158 TL SWC with polyurethane, and loading them over 3.5 gr Bullseye in .38 cases. Anyone see a reason not to try it?

[cohutt]

I just got back from the range with my nephew. We collectively emptied about 1600 cases, 38s and .357s. I was pleased with the Lee 158 TL SWC and the standard Lee Alox lube in .38. As I plan the menu for reloading, I thought I'd revisit Johnson's Paste Wax. Then I thought about using polyurethane. We have wood floors in my house and touch up a few spots with polyurethane. The first time I tried JPW, I had a problem with JPW flaking off the boolits in loading, and thought polyurethane might bond to WW boolits better than JPW. At .38 pressures and velocities, polyurethane just might be sufficient as a boolit coating. Has anyone tried it? Have any thoughts? I'm thinking of tumble lubing about 100 Lee 158 TL SWC with polyurethane, and loading them over 3.5 gr Bullseye in .38 cases. Anyone see a reason not to try it?


I'd say- disaster.

Wax=a Lube
Poly= not a lube, imho

ever shoot russian ammo with the laquer coating in a hot chamber?

[snuffy]

Polyurethane is a plastic, not a wax. It has solvent in it to evaporate, leaving the plastic to bond to the wood. I doubt you'd like having to remove plastic that rubs off in your bore![smilie=1: [smilie=b: :groner:

[357maximum]

I say go for it and give it a whirl, let us know how it goes, you do not know till ya try. Plastic and wax are somewhat chemically similar, it may work.....YOU may want to invest in some acetone or acetone based plastic fouling remover for shotguns if all does not go well, but how else will YOU KNOW?

I KNOW plastic removes alot easier than lead from the bore (synthetic 2cycle motor oil based lube test)

[whisler]

Polyurethane is a high molecular weight resin, not a wax or lubricant. If you have to remove cross-linked (dried) polyurethane from the bore of your gun, you will need to use paint stripper just to soften it enough to scrub it out. At the temperature you will generate in firing the piece, you definitely will cross-link the the polyurethane to a fare - thee - well (old English for "boy have you done it now"). I don't have much experience with casting yet, but I do know polyurethane and I know you definitely don't want to do this. Save the polyurethane for the grips or stock and use something else for lube.

[357maximum]

Just how hot does a boolit get in it's trip down the bore? hmmmmmmmm

I would assume the poly would be dried/hardened before loading.


I have never tried it, but I know it will not work.........hmmmmmmmmm


How long was the earth flat and why, before it suddenly became round?

[shooting on a shoestring]

Well, I'm gonna do it. When I get through with this post I'll go tumble lube with the polyurethane. When they cure, I'll reassess, and if the urethane bonds better to the boolits than JWP, I'll load some .38s. I'll fire them in my 1-7/8" barreled J-frame. Then if I do gets lots of bad stuff in the barrel, it will only be a 1-7/8" problem.

I'm thinking waxes are carbon polymers with chain lenghts running about 20 to 30 or so units long. Urethanes are carbon polymers with a few nitrogen atoms in the chains triple bonded to carbon atoms, chain lenghts running considerably longer after crosslinking (I believe at the triple bonded nitrogen group) during hardening. During firing, I expect the urethane polymer to be left mostly intact like the shorter chained waxes, but some will combust, especially on the bottom of the boolit. The combustion products should be the same as for waxes, except for the triple bonded nitrogen groups, which are cyanates. I suppose in theory, there will be a very, very small amount of cyanates liberated as products of incomplete combustion (PICs), but I expect that the possible toxicity from that process to be orders of magnitude less than the toxicity from the nitroglycerin PICs, areosol Pb, and heavy metals from the priming mixture.

Whisler, you raise a good point about the possiblity of goop in the barrel. My first line of defense will be a handfull of traditional (Felix) lubed boolits with a heaping helping of cream of wheat between the boolit and Bullseye. If that doesn't clear the problem, brush and solvent surely will, given the appropriate dose (and I do have a suitable selection of solvents).

357 Max, thanks for the encouragement, but I notice you didn't mention any plans for a joint venture.

I'll post more after the deed is done.

[Freightman]

coat the bore with the JPW and shine, might keep the poly from sticking.

[Ricochet]

Try it and let us know how it works out, Shoestring.

[andrew375]

Give it a try, what have you got to loose?

I've not had any problems with putting high density polyurethane moulding powder, AKA SuperGrex, behind cast bullets. So I don't see a problem.:drinks:

[felix]

Urethane is a different animal than methane, ethane chemistry, which the gun buffers typically are. The urethanes are made for heavy duty flex, and return to "center", applications and therefore can be very "sticky" when decomposition starts. However, the temp-time factor might not occur in a gun application, but if it does, then there could be a major cleaning problem after the shooting session like was suggested earlier. ... felix

[leftiye]

While we're at it, Can any of youse chemists figger out if there's a paint that might work as a dip/jacket for boolits?

[357maximum]

357 Max, thanks for the encouragement, but I notice you didn't mention any plans for a joint venture.

I'll post more after the deed is done.


I have done so much playing with waxes , that it will be awhile before I play some more...ureathanes are on the list...but they are down there a ways.....go for it and report back...it will not hurt the gun if you have to apply some elbow grease if it does indeed fail. Will not hurt you either...besides apparently it is thee only way you are going to know for sure.

I have had failures too...it is not that big a deal, especially when you find panacea.

[shooting on a shoestring]

They're loaded. 100 rounds Lee TL 158 SWC tumlbe lubed with Fast Drying Polyurethane, two applications (spanning abut 5 hours thanks to some Central Texas sunshine) sitting in .38 Spl cases over 3.3 gr Bullseye, CCI 500s in the pocket.

As a control, I also have Alox lubed TL 158 SWCs, same load ready to go.

Firing will probably happen within a week. So far they feel and look great. The urethane stuck firm to boolits and did not show any inclination to flake during loading. The boolits feel slick and did not deposit anything on the bullet seating plug. The proof will be in the pudding. I'll post after shooting (and cleaning) and divulge the results.

[AZ-Stew]

Please post the S/N of your revolver so we'll know which one not to buy after you find out you can't scrub the residue out of it.

Regards,

Stew

[redbear705]

I work in plastic injection molding and have used polyurethane in numerous jobs.......there is one thing I can tell you....when polyurethane gets over heated it turns to a nasty sticky messy crud that will take hours just to get the mess off the mould/mold.

That over heated stuff is so sticky.............no way will I put that in my gun.

The polyurethane finish you are using may be a different animal but I dont think it will be that different when launched down the tube with a couple thousand degree flame burning it up as it gets smeared along the barrel.

Let us know what happens....:)

JR

[LiquidLead]

Polyurinstain (where still legal) comes in several species, some of which cure out pretty hard. Besides the possibility of a nasty buildup that has been pointed out, I would be concerned about the abrasive effect of firing multiple rounds. :(

I would look pretty closely at the bore after the first couple of rounds. I know some of it will dull planer knives badly. Some of it will really mess up a drum sander, also.

Good luck.

Mike

[gray wolf]

Any chance of a Polly buildup in the bore and creating an obstruction??
Like lead does in some glock pistols??
Just a thought.

[felix]

Yes, very possible, just like any lube over time. Different lubes give different results after being fired and left to harden, depending on factors too numerous to make simple sense about. ... felix

[shooting on a shoestring]

To the point, leaded like crazy.

The load: R-P .38Spl cases, 3.3 grains Bullseye, Lee .358 TL 158 gr SWC tumble lubed with two coats of MinWax Fast Drying Poly Urethane Clear Satin Finish. The Poly Urethane coating filled the boolit's lube grooves to almost flush. They loaded great, no flaking.

The test weapon: S&W J-frame, Model 60 in .38Spl, 1-7/8" barrel, groove diameter .357, throats .358.

What happened: Barrel was pre-lubed with a patch of Marvel Mystry Oil followed by a dry patch. First shot - barrel looked slightly fouled, second and third shots - barrel showed leading in corner of grooves the lenght of the barrel. After the fifth shot, the barrel was heavily leaded. I did not see any plastic coating, no goop, no burned on crud, just very heavy leading. 5 shots of Cream of Wheat filled cases powered by 2.8 gr Bullseye and Alox lubed TL 158 SWC, the barrel was still leaded. The revovler was cleaned with Ed's Red, 10 strokes of a bronze brush. The clean barrel was left wet with Ed's Red, 10 more poly urethane coated bullets, accuracy began deteriorating. Velocities were running about 720 fps with SDEV of 7 to 9. Revolver was cleaned with Ed's Red, 10 strokes of bronze brush, still leaded, brushed 20 times, Ed's Red, clean barrel, experiment aborted.

I fired the same load using Alox lubed TL 158 SWC coated twice, no appreciable change in velocity, 50 rounds fired, light leading the lenght of the barrel, easily shot out with Cream of Wheat loads.

Conclusion: Poly Urethane is not a suitable lube/coating for boolits, but does not leave urethane in the bore, just lots and lots of lead. I did see some flakes of poly urethane on the outside of the fired cases upon extraction. Mostly near the case mouths but some as far back as half way. My guess is the urethane came off the boolit before it got into the barrel. The throats had none to only a slight bit of lead in them, of course they only saw 1/5th of the shots the barrel did.

[cohutt]

well thanks for trying and posting the results.

I just put a little alox in the JPW and it doesn't flake like pure jpw. Also much less nasty and sticky that pure alox.

[Ricochet]

Thanks for the report. Now we know something that definitely doesn't work.

Cohutt, you're starting down a road I started on 9 months or so ago, adding things to JPW, starting with liquid Alox. It does improve on the pure JPW, IMO. I've currently got a mixture that started off as a can of JPW, and also has in it Alox, toilet bowl wax, and a bunch of beeswax. It's great stuff for dip lubing rifle bullets, works fairly well for tumble lubing pistol bullets (it's a little gummier than ideal for that), and is the best stuff ever for dipping out of the can with a plastic knife and smearing over the tops of the balls of a cap and ball revolver. Just about eliminates leading in my Colt Walker replica, which leads terribly with all the traditional BP lubes.

[mag_01]

Good report thanks --- One thought would car wax do it for you --- My son gave me a clear wax goes on easy leaves no white residue -- might be something to look at -- could be put on with a cue tip . I just cote my TL boolits with Lee TL ----- light loads 1 cote ---- heavy loads 2 cotes ---- Mag_01



One way or another " Get her done".

[leftiye]

So, how about something else that could be painted on? Anybody? On another thread a guy used high temp engine enamel ( I think, but my memory is probly wroong). Said it shot okay , IIRC. He was more interested in protecting the base of the boolit. I don't think that temps are that much of a problem, and am more interested in protecting the bearing surface of the boolits.

[Bret4207]

Years ago, 20-25, there was a graphite bearing boolit dip on the market that was supposed to work. The thought of handling each boolit with tweezers and then trying to arrange them base down seems a lot of work for something that performed about like Mule Snot or JPW. I suppose you could add graphite to JPW and thin with mineral spirits to the point it would spray and use a pump sprayer if thats your aim.

[357maximum]

And now YOU know what that particular combo is like, and nothing will ever replace actual experience.

Maybe a softer setting urathane would do better maybe not, only the man that has tried it knows for sure.

I can tell you that mixing straight melted beeswax with mineral spirits in search of a different tumblelube does not work well either, but YOU still do not know it will not work.

I can tell you that mixing melted beeswax with pure acetone does not work and makes for some neat white globulations of crap and some knock out capable fumes...same deal

I commend you on the just doing it, good job.:drinks:

[Ricochet]

+1 on the "only YOU know it works or it doesn't if you've tried it" part. I've had, and posted, good results with White Lightning bicycle chain lube in several fast GC rifle loads. Others have had horrible results in some seemingly rather undemanding pistol rounds with the stuff. I still haven't figured that one out. I thought I'd found some great stuff.

[Charlie Horse]

They laughed at the Wright Bros.

[truckjohn]

They laughed at the Wright Bros.

No, we laughed "with" the guy who lubed his boolits with glue..... How about using Epoxy or Phenolic as boolit lube?
JB Weld or Plastic Steel probably work about as well....

If he said "Hey All, I want to try out lubing my boolits with Epoxy.... we would have said "Hey man, bad idea."

Polyurethane.... main ingredient in:
Gorilla glue
Elmer's "Pro Bond" glue
Great stuff canned spray foam
Right stuff gasket sealer
The new Bomb proof tub caulks

As another said... it's a cross-linked thermo-setting resin....
1. Does not melt -- just hardens more with temp.
2. Degrades when too hot -- Into impenetrable sticky black tar
3. Lets lube our boolits with JB Weld and see what happens?

I think using it after drying was a wiser choice than wet. You would probably have a new permanent "High Performance Coating" in your barrel otherwise.... and possibly firing boolits glued into the shells may not have gone as planned.

John

[leftiye]

A guy on another thread (Teflon Tape Boolit Lube) mentioned a teflon pipe thread sealant that brushes on. Might be the elusive "paint on boolit lube?"