Just slugged my bore...

[Jech]

Some time ago, I bought 1k "Softball" 18BHN 230gr LRN .452 bullets from Missouri Bullet Company, after many posts and threads on different forums and expending the full quantity of bullets, I am still without a resolution to the leading in the first 1" of my barrel, the onyl thing I had left to do was slug my bore.

http://www.youtube.com/watch?v=CR_WiL8Dkgw

Following this technique, my only deviation from his process is I used one of my own cast boolits instead of a round ball. My 3 sets of grooves are .4505" - .451" as close I can tell using my Lyman 6" dial calipers which only indicate the the thousandth.

My first main question is could a slightly undersized bore create forcing cone leading?

The second is does this mean I should buy Lee's .451 sizing kit and not use my .452 sizing kit since I would be more than .001" over diameter already?

[onesonek]

Personally imho,,,"as close as I can tell" using a caliper is only slightly better than a guess,,, sorry, just not accurate enough. When in doubt, shoot alil bigger. In reality, you can shoot as big as cast, as the loaded round will chamber easily. The barel will make it right, if you are running the pressures to match. From what I can tell in my reading's, is that the leading you described is from undersized boolits. Being .0001"+ over slug is a good thing. The boolit you call "softball" really aint soft at all and will need some pressure behind it. BHN 18 is harder than Lyman #2 and Roto's HardBall. You likely need pressure's around 26000 psi, and guessing roughly 23000 cup for that hard of boolit to shoot properly.
If you use your own cast boolit for slugging, again imo, would be ok if you fattened it up some first and that it is nearly pure lead or at least a very soft alloy. But without a micrometer that allows for .0001" readings, you just don't know where you are really at.
If it is slugging at .4505-.451", then I would use the .452 sizer, or if the are dropping .452-.4525", iI would shoot as is.

just my 2 cents

[bhn22]

Most leading in 45 ACP autoloaders seems to be caused by over-doing the taper crimp & swaging the bullet down below your groove dimension. Pulling a loaded bullet & measuring it will tell you if this is happening. The accursed Lee "Handgun Factory Crimp Die" also swages bullets down in the case. It seems like a good idea until you realize that cases from different manufacturers often have different case wall thicknesses. If you get a thick wall case, you get your bullet squished down to a smaller diameter, even if it's not appropriate for your situation. 9mms have these issues, plus a few others of their own, because of the tapered case.

[geargnasher]

Jech, slugging your bore should have been the FIRST thing you did, even before selecting a sizer and a boolit mould for your gun, since accurate groove dimensions are essential to knowing what mould and sizer to get in the first place.

Coupla things you need to know. First off, your 6" calipers are barely fit to measure COAL, much less a critical bore dimension. The scale will measure to the .001", but you need half that, and the tolerance is probably at least plus/minus that same amount, so if the bore is .4510" like it's supposed to be, it might measure .4520" or .4500" just on the tool's tolerances. You need a good, C-clamp style 0-1" MICROMETER to measure slugs with any accuracy. The other thing is you should be using soft lead to slug your bore. This is not because it's easier to pound soft lead through the barrel, or that it's easier on the gun to do it, it's because pure lead is "dead", that is to say has no elastic memory or "springback". If you pound a typically alloyed boolit through there and measure it, it will be bigger than groove diameter because it will have sprung back some after exiting, and the bore will have expanded slightly as you drove it through, like a snake swallowing eggs.

Now, on to your leading issue in the first inch of the bbl. I'd be willing to bet you have one or more of three things wrong: One, the boolit is too small when it first hits the rifling and you're getting blowby. After engraving, the displaced lead my close up the gaps and achieve bore obturation, and the leading stops further up the barrel. Two, there isn't much "leade" in the barrel and the sharp edges of the rifling lands tear up the boolit causing blowby and leading. Three, you are using a powder that is way too fast, causing the boolit to slam into the barrel too fast at launch and skid straight through the rifling for the first half-inch or so, and that makes the land engraves wide and leaves a gap for blowby. Again, the booit may obturate the bore further down, but not at first, and that would explain your leading. Copper fouling and rough bores can also cause your issues, I'm assuming you cleaned ALL the copper fouling out before you tried shooting cast, didn't you??????

Gear

[Larry Gibson]

Jech

If those commercial cast bullets had a hard wax lube then leading of the first 1" or so of barrels is quite common. It is the wax lube that is the problem. I've washed enough of the hard was lube of thousands of commercial cast bullets for numerous cartridges, including several thousand for the .45 ACP in my M1911s (3 of them). All the bullets at less than 1200 fps leaded the 1st 1" or so of the barrel until I simply washed the hard wax lube off and either TL'd in LLA or relubed with Javelina. Then I got no leading. Again, it's the hard wax lubes which is just convenient for the bullet caster/sellers not the shooter.

Larry Gibson

[Bret4207]

Good advice all around. Fit is king with cast, no matter how hard it is. Lubes found of many commercial boolits are geared towards looking good and remaining on the boolits during shipping. A properly fitted boolit with a good quality lube and precision measuring tools to determine fit are where you need to start.

[Jech]

Looks like I'm up a creek without a paddle!

All the sporting goods stores in my area have shifted to steel fishing weights and I don't have any pure lead...just range-mined lead. I also don't have the cash for a set of micrometers >< Ugh!

FWIW I made a dummy with an unsized boolit that measured .455" with 1/32" of the boolit's side exposed. When I tried to chamber these dummies, the slide would not fully lock into battery without a little extra love tap. Extraction was very difficult; analysis of the dummy showed a slight-but-visible ring of lead displaced around the boolit where it (the lead) obviously headspaced into the freebore, not on the case mouth.

The next set of dummies went through my sizing die...all measured a diameter of .452" as advertised. This set of dummies chambered well enough, however when I used the barrel as a case-gauge, the clink was not as sharp as one would hope, and when I lifted the dummy back out by my fingernails, it was a little sticky which tells me it was on the lead but just barely.

The 3rd set of dummies was again using sized boolits but deliberately seated deep so the cone was set back past the case mouth by just a hair. The goal here was to make sure that I'm not dealing with a chamber that's too tight for a .452" boolit and (sorted) Winchester brass I shoot. This set gauged out just fine, a very loud clink.

Now that I hear hard-wax-based lubes commonly lead barrels even when conditions are appropriate, I need to see if I can pilfer ingredients from friends/family for some pan-lube.

[Bret4207]

FYI- Places like Harbor Freight and the on line tool stores regularly sell 1" micrometers for around $20.00. Often you can get them for around $10.00 on sale.

http://www.harborfreight.com/0-to-1-inch-range-digital-micrometer-895.html

At 45 ACP speeds even the simple addition of Mule Snot (Lee Liquid Alox) will help in the lube dept.

Your range scrap may well work. Just be sure you make a good slug.

[Bob J]

This is a pretty cool way to make your own slugs using a unsized piece of brass and dead soft lead....

Part 1
http://www.youtube.com/watch?v=KuNoo4m6jso

Part 2
http://www.youtube.com/watch?v=KuNoo4m6jso

[Three-Fifty-Seven]

Only thing I would add to the above videos is a tad of oil before slugging . . .

[NHlever]

I like to use case sizing lube when I slug bores. My reasoning is that is a forming lube, and it has worked out well for me.

[Jech]

I have a bottle of RCBS Case Lube on hand, worked well enough for my first attempts.

Those videos Bob J linked are interesting, looks like I should use a 45auto case that's been fired and tumbled but not deprimed. Should be able to try this later today :)

[Char-Gar]

Answers to your question:

1. An undersize bore won't cause leading.
2. No need to buy a new sizer. The .452 will do just fine.

Note:

As others said, calipers are not the way to measure a slug. Use a micrometer.

The leading in the rear of your barrel is most likely caused by a bullet too hard, rough forcing cone or both.

If you have a Ruger sixgun there might be issues with bullet size and cylinder throat size, but again you didn't say. If you are talking auto pistol different rules apply.

If you are talking autopistol, your problems are those crappy store bought bullets. See all of the above.

I continue to be amazed by folks who ask questions and don't give enough information for an informed answer.

[Jech]

My apologies, I post on multiple forums as I learn and overcome different obstacles...sometimes I forget which ones I've already given the details on ><

This is for my Springfield Armory XD 5" Tactical 45ACP, wheelgun caveats won't apply. Also, I'm not overly concerned with troubleshooting the leading issues I had with the MBC bullets...I ran out of them so now it's time to make my own :) My original question is in preparation of shooting my own cast boolits so in essence, slugging here is the first thing I'm doing :P

------------
As a sidenote, "Those crappy store bought bullets" are made by a respected member of the boolit-casting community (as well as this forum) who makes their living through these bullets. Out of loyalty for a honest business with a quality product, I would ask that such comments about the products in question be kept objective.

[Bob J]

That was what I liked about them as well..... Nice way to easily make a perfect sized slug out of materials typically readily at hand... Of course the technique is limited to straight walled cases but still that covers a lot of ground.....;)

Also agree with the lube comments...... I lube the bore and tumble lube my slugs before I drive them through......


I have a bottle of RCBS Case Lube on hand, worked well enough for my first attempts.

Those videos Bob J linked are interesting, looks like I should use a 45auto case that's been fired and tumbled but not deprimed. Should be able to try this later today :)

[Char-Gar]

Jech...

There are bullets you can purchase from small production folks who hand cast, size and lube with quality materials. These are as good as you can produce at home. Bull Shop is one such provider of cast bullets. Dry Creek is another fine producer that is now back in limited production. I am certain there are others.

I have never seen any of these in a gun store. The ones I have seen are mass produced, machine cast bullets. They have a bevel base to help them fall from the automatic casting machines better. They alloy is too hard for many uses and wax lubricant is worthless as a bullet lube. It is designed to stay in the grooves during packing and shipping and not for it's effectivness as a bullet lubricant. The design of the bullet and the materials used are selected for speed and quanity of production, and not for their suitability for their stated use.

In short, every "store bought" bullet I have ever seen is pretty much worthless and we get many posts on this board about folks with your issues that comes from these "crappy store bought bullets". They are an ongoing problem for the novice cast bullet shooter.

I have no problem with a guy trying to make a buck by producing and selling these above knd of bullets. This is America after all! The old maximum of "caveat emptor" still applies. If the shooter is happy with what he buys, then it is no businsss of mine. But, when they come here with issues related to those bullets and are asking for help, that is another matter.

Now, I was not looking over your shoulder when you bought and loaded your bullets, so only you can decided what you bought.

My comments were not based on prejudice but experience. Sometimes experience matters and we are not required to be open ended/objective about everything is this world. After we have been snake bite a few times, we learn to avoid snakes. I am sorry you were offended, but I gave it to you straight up as I see it. Can I be wrong? Of course! Am I wrong about the vast majority of store bought cast bullets? Nope!

[MtGun44]

Enco's current flyer has a Fowler .0001" carbide tipped vernier mic for $27.99 plus shipping.
Part number is ET619-3106. Web site is

http://www.use-enco.com/CGI/INSRHM

put the part number in the search window. They also list a "import" (no brand name)
direct reading .001"digital mic (numbers in a window, not electric) with a .0001" vernier
scale (you will need to learn to read a vernier scale - not difficult- for either
of these mics) for $19.95; PN: ET600-2311. Carbide faces, ratchet stop, sounds pretty
darned decent, too and WAY good deals, both of them.

Lots of good advise. Better lube, big enough boolit, making sure that seating in
your brass or exiting crimp does not size down the boolits.

Bill

[grubbylabs]

Wow great videos.

So do I need to drive the slug all the way through or drive it in a little at each end and measure both? The volume was a little low for me to hear the whole thing really well.

[Three-Fifty-Seven]

On my revolvers I measured both ends, Ruger's tend to have a "restriction" where they are threaded into the frame, but other guns can also have this problem . . . my rifles, and auto, I just drove it through . . .

[DIRT Farmer]

Just rembember guys, you had to learn some to have an idea of what questions you needed to ask.
Jech, I shot a lot of bought bullets when I shot compation, when shooting at a 10x12 inch plate at 12 yds, it don't take a lot of fine tuning for the load, just hit it, you got to clean the barrel anyway and I did not always have time to cast what I needed. Picking up a few boxes of 500 beat standing in a hot shop when I needed sleep.
Now I have the time to cast but my times are so slow that it is just a reason to visit with the guys when I go to a pistol match.

[fredj338]

I also shoot an XDTAC. They have very shallow throats so the "Sticking" may not be an oversized bullet but one seated too long. This is a problem w/ several designs, even RN, if the ogive is not as long (Lee 228gr). The issue coukd be your reloading technique. Are you using a LFCD to final crimp? This can size down a perfectly fitting bullet & make it slightly small. That & the 18BHN, uberfast powder like BE, or TG, & the wrong lube for the pressure used, can cause this prelim leading as the bullet won't seal the bore until it gets moving. I moved away from harder bulelts in all my 45acp, the pressures just don't support them & leading has been reduced. I also don;t use a powder faster than WST & use CarnubaRed or sim lube.

[badbob454]

nice video's ill have to slug my ruger super redhawk 454 casull leading dosent seem to be a problem but its easy to do when you know how and now i do thanks for the video'S

[243winxb]

From Lee's link below >
If it appears near the chamber, chances are that bullet diameter or hardness are the cause.

A diameter too small and/or too hard an alloy will allow high pressure gas to leak past the bullet, which erodes the bullet and leaves leading near the chamber.
[/COLOR]
If the leading first appears on the leading edge of the rifling (if you imagine the bullet being pushed through the barrel, you will note that one edge of the rifling does most of the work of imparting a spin to the bullet. This is the edge you see when you look through the barrel from the breech end) the bullet might be too soft, and/or the velocity too high.

If the leading appears in the second half of the barrel, the bullet is running out of lube. You should see a star shaped pattern of lube accumulate on the muzzle. This is an indication that there is a little excess lube.

]