Molten Lead From Muzzle

[Ricochet]

Went to try out a new load today in my Mosin M91/30. It slugs at .312". I always keep the bayonet mounted on this rifle. If I didn't, I'd've never known about this. The boolit I was shooting was the .312" Fat 30 Tumble Lube boolit from a group buy a few years ago, a 165 grain Loverin with Lee style mini grooves and a plain base. I lubed them with LLA (these were the ones that caused the phenomenon I'm reporting), and also tested some with another promising tumble lube agent. Alloy is about 1 part wheelweights to 3 parts soft scrap lead, water dropped. They're a little harder by crude hardness tests (hand pressing the edge of a screwdriver, that sort of thing) than air cooled wheelweights. These boolits are intended for low velocity shooting, but I thought I'd see what happened with a load of 3.1cc (about 37.5 grains) of IMR 7383 under them. Gave a muzzle velocity averaging around 1850 FPS, a bit fast for plain base boolits of relatively soft alloy. From the first few shots with the LLA, I saw a heavy, rough, chunky looking black buildup on the base of the bayonet facing the muzzle. There was a nice greasy lube star on the muzzle, and I thought I was seeing lube and powder soot. I can't comment on grouping, as the POI was somewhere way off from where it shoots with Hungarian heavy ball, I couldn't see where the boolits were hitting, I couldn't get closer due to the range being in use by others, and I never got it on the paper. But the muzzle showed light streaky leading, nothing that bothered me. When I switched over to the other lube, which I'll have to test further, no more lead showed up in the bore, and the buildup on the bayonet stopped growing. The black mess got coated with a trace of white ash from this lube.

When I got home and went to clean my rifles, I expected that stuff to wipe off the bayonet easily. As I said, the bore was barely leaded and there was a nice greasy brown deposit on the muzzle crown. But the stuff on the bayonet was HARD and rough! I polished it by rubbing, and it was silvery and shiny! It was lead, soldered tightly to the steel bayonet! It was in the form of a fine spray, mostly, but there were several large drops just like solder blobs. Had to scrape it off with a pocket knife, it was really stuck on there!

The same alloy in the much heavier, gaschecked 8mm Maximum boolit, lubed with LLA, over the same powder charge at about 1800 FPS, shoots very nicely and made several respectable groups from my Persian Mauser right after this.

Now I'm not surprised that the Persian would shoot better and lead less than the Mosin. The Mosin's a WWII vet, and the Persian's barely used if at all before I got it. The bore's slicker'n slug snot. The Mosin's is a bit frosty. And I was shooting plain based boolits at gascheck speed from the Mosin. But I sure was surprised to find it actually spraying molten lead like that! And I'd never have thought anything of it if I hadn't had that bayonet on to catch the spray. The bore leading is very light and didn't bother me a bit. Wish I could see what some of those boolits looked like!

I'll bet this sort of thing's going on in some of the cases we all know about where a particular boolit in a particular load with a particular lube doesn't cause bore leading problems but won't shoot well.

I'm not going to do any further testing with this load and these boolits. They need to stay with the light, pistol powder loads at modest velocities.

[floodgate]

Rickochet:

"When I got home and went to clean my rifles, I expected that stuff to wipe off the bayonet easily. As I said, the bore was barely leaded and there was a nice greasy brown deposit on the muzzle crown. But the stuff on the bayonet was HARD and rough! I polished it by rubbing, and it was silvery and shiny! It was lead, soldered tightly to the steel bayonet! It was in the form of a fine spray, mostly, but there were several large drops just like solder blobs. Had to scrape it off with a pocket knife, it was really stuck on there."

As I think I mentioned a few days ago, I had the same thing happen with a M-N M44 with the bayonet extended, #311407 w/LLA, and 16(?) gns. Red Dot. Moderate leading in the bore (bullet 'way undersized!), but heavy and very tenacious leading on the inner face of the bayonet blade. Does anyone make a really GOOD bayonet lube?

floodgate

[Ricochet]

Hmmm, I missed or forgot your report. That's a good idea about precoating the bayo with something to keep it from sticking. But what it's really got me wondering is how often we're all spraying molten lead from the muzzle with no clue it's going on?

[PatMarlin]

Doesn't Bullshop have a bayonet lube?... :mrgreen:

[kodiak1]

Ricochet
I would be damn suspect of my mix of my melt. Sounds to me like you are shooting more of a solder than a lead.
Ken.

[44man]

What was the other lube?
I have always said LLA rubs off in a short distance and it also burns so you are shooting a bare boolit down most of the bore. Makes it lead at that speed and the hot gases are melting the leading behind the boolit.
Add to that some skidding from the soft lead and gas cutting from the poor fit that is developed from skidding and leading.
Also, what is IMR 7383??????

[Ricochet]

IMR 7383 is well known to surplus powder burners, and has spawned a bunch of threads on Cast Boolits. It had one application only, the second version of the .50 caliber spotter cartridge for the spotter rifle on the 106mm recoilless rifle. In the cartridges I've tried it in so far, it gives velocities for charge weights equal to IMR 4350, but it's a bulky powder that's only about 7/8 as dense so you can't load a maximum pressure charge in most of the mid-size cartridges. It just reaches the lower end of 4350 loads. In this Mosin load filled to the base of the shoulder, there were partially burned powder kernels left in the cases and showered over the Chrony.

The other lube I'm experimenting with, just starting, is White Lightning bicycle chain lube.
http://www.performancebike.com/shop/Profile.cfm?SKU=17143&item=40-1654&slitrk=search&slisearch=true
It's a waxy solution that also contains a white precipitate that has to be shaken back into suspension from time to time, probably a metallic soap as used in greases. It dries to a nearly clear, slightly sticky wax. Much prettier and neater to handle than LLA, and a lot slicker. Doesn't attract and hold much dirt; as advertised, it sheds it off. It clings to metal very well, lubricates under the high local surface pressure conditions found in a bike chain drive (where the instantaneous peak torque is as high as a small block Chevy can put out and the contact surface areas are very small), is durable enough to last over 100 miles between applications on a chain, and obviously can survive well in a dirty environment.

I also have some Boeshield T-9 to try out. It's another dry wax solution sold principally as a corrosion inhibitor, that was also quite popular for bike chains in the '90s. Wouldn't surprise me if both of them are repackaged Lubrizol rust inhibitors, as is LLA. Several of the ones on Lubrizol's site fit the general description of an oil/solvent based solution that dries to a waxy film.

Haven't found any prior reports of these being used on boolits. I think they've got good potential; I'll report further results as I come up with them. Anybody else who wants to give 'em a try, please post the outcomes also.

[Ricochet]

Just a little addendum for those who think my alloy might be too low melting: I'd used the same stuff for some gaschecked 8mm boolits, and after water dropping them and putting off the checking till next day, they were too hard for my Lyman press to force through a .323" Lee sizing die, so I oven treated them at 475°F, quenching them and immediately sizing on the checks before they could harden. There was no sagging or slumping whatsoever during the heating, and they hardened back up nicely. I wanted them softer than pure wheelweights heat treated, and they are, but they're noticeably harder than air cooled wheelweights.

The revelation for me is that looking at bore deposits doesn't tell the full story of what's happening to the boolit. Just looking at the bore, I'd think the boolit and lube were working pretty well, but I was splashing lead all over that bayonet! It stuck to the bayonet a lot better than it did to the bore, perhaps because the bore got coated with LLA. It was certainly making it to the muzzle and building up a brown greasy deposit on the crown, not burning completely away by any means.