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Der SchizKoph
02-28-2011, 06:10 PM
Could not find anything about this, i have been having some ideas about slugging the barrels on some of my pistols, and was wondering if this has been tried or if it will cause problems:

What i want to do is to plug my barrel about an inch from the end, then pour lead straight into it, then when cool, tap it out

Has anyone tried this or will it cause serious problems? Thanks

Bass Ackward
02-28-2011, 07:03 PM
Could not find anything about this, i have been having some ideas about slugging the barrels on some of my pistols, and was wondering if this has been tried or if it will cause problems:

What i want to do is to plug my barrel about an inch from the end, then pour lead straight into it, then when cool, tap it out

Has anyone tried this or will it cause serious problems? Thanks



I would advise against it.

Slugging should be the mantra here. If it were up to me, no advice would be given until folks slugged, but this is America. Land of the free and home of the public assistance crowd.

Same results can be obtained with three pure lead slugs. One in the muzzle and out. One in the throat and out. And one all the way through for "feel" and the smallest measurement. Common sense should tell you that the muzzle should be the smallest measurement and the slug needs to G L I D E through the bore as smooth as a baby's behind.

Blammer
02-28-2011, 08:39 PM
if you do that you'll likely never get the lead out that you pour into it.

I would highly recommend against doing that.

dragonrider
02-28-2011, 08:45 PM
Here you will find a whole list of videos that explain the how to's slugging a barrel.
http://www.youtube.com/results?search_query=slugging+a+barrel&aq=1

The process you descriped can be done but not with lead, you would use a product called cerosafe. It has a very low melting temp and is used for making chamber casts etc.

stubshaft
02-28-2011, 08:49 PM
It's basically like pouring a lead lap. The problem is not with the lead sticking in the muzzle (because it won't) but that it will likely be well undersize. Like pouring alloy in a mold that is too cold. You can heat the barrel slightly with a heat gun to get better fillout but chances are that it will still be undersize. A brass rod near bore diameter can be used to drive it through.

Charlie Two Tracks
02-28-2011, 08:52 PM
I would think that you would have to have the barrel real hot so the lead would make it all the way down. 600 deg lead going down the barrel and then what would happen if there was a constriction someplace. Not good.

462
02-28-2011, 10:33 PM
When it's as easy to do, as Bass said (and it really is) why even comtemplate a more complex method which will produce very dubious results, at best.

markinalpine
02-28-2011, 11:29 PM
Could not find anything about this, i have been having some ideas about slugging the barrels on some of my pistols, and was wondering if this has been tried or if it will cause problems:

What i want to do is to plug my barrel about an inch from the end, then pour lead straight into it, then when cool, tap it out

Has anyone tried this or will it cause serious problems? Thanks

If you DO decide to go ahead and do it anyway, please take lots of pictures or better, a video, so we can watch :popcorn:
Especially when you try to fix it :kidding:
Mark :bigsmyl2:

stubshaft
03-01-2011, 12:13 AM
I would think that you would have to have the barrel real hot so the lead would make it all the way down. 600 deg lead going down the barrel and then what would happen if there was a constriction someplace. Not good.

Doesn't have to be that hot and all you need is a 1" - 2" section.

lwknight
03-01-2011, 01:09 AM
You will get an undersized reading just like casting into any cold mold. I really don't think that you would want to pre heat your gun to 400 degrees.
At least with cerrosafe the shrinkage compensation is a predetermined measurement.

oscarflytyer
03-01-2011, 01:12 AM
Cerrosafe Chamber Casting Alloy!!!

geargnasher
03-01-2011, 01:38 AM
Why is it that we seem to always have a better new idea before trying the tried-and-true old idea? I'm all for new ideas, but good new ideas are born of the need to improve upon existing ones that have proven inadequate somehow. Just slug the freakin' thing already.

Gear

Bret4207
03-01-2011, 08:07 AM
You guys do know Cerrosafe has a shrinkage factor, right? I forget what percent it is, but it used to be on the package.

Don't pour molten alloy into your barrel. I've made dozens, if not hundreds of laps and they ALWAYS come out undersized, ALWAYS. You want precise measurements then slug it and use a tenths reading mic that you know how to use properly.

btroj
03-01-2011, 09:02 AM
Well, at least the thread has the right title.this would be reinventing the wheel. Too bad the existing wheel works so good!

Drive a slug thru the barrel and get on with things. It would be so much easier, and better, to go old school. Some things just don't need improving upon.

Brad

Jim
03-01-2011, 10:15 AM
RED(Reverse Engineering& Designing) Method-
Identify the ultimate goal and determine the easiest, safest, most economical approach.
Kinda' like drivin' across country. If wanderin' around lookin' for a road that MIGHT get you there doesn't bother you, by all means, go pour lead down your barrel!
However, if you wanna get somewhere in a timely manner at the least expense, MAPS ARE AVAILABLE.

WILCO
03-01-2011, 10:29 AM
What i want to do is to plug my barrel about an inch from the end, then pour lead straight into it, then when cool, tap it out


I've done some foolish things in my life too. :drinks:

AZ-Stew
03-01-2011, 12:00 PM
You guys do know Cerrosafe has a shrinkage factor, right? I forget what percent it is, but it used to be on the package.

Well, kinda...

Here's the scoop from the Brownell's web site:

CERROSAFE® CHAMBER CASTING ALLOY
Mfr:BROWNELL'S
Price:$28.99 - $45.99 Status:In Stock
Made In The U.S.A.
Never Wears Out- Use Over And Over
There are various products on the market which can be used to make a cast of a gun chamber. To be certain that the product we are offering you is the best and most practical, we contacted the basic manufacturer. They recommended Cerrosafe because of its unique features. Unlike Woodsmetal which swells upon cooling and cannot be removed from a gun chamber, Cerrosafe shrinks during the first 30 minutes of cooling and then at the end of an hour, is EXACTLY chamber size. At the end of 200 hours it will have expanded approximately .0025". This factor is well known by all toolmakers and they will take it into consideration when making dies or reamers or gauges from your cast - if you will tell them the cast is of Cerrosafe. Cerrosafe melts between 158° - 190° F. It should be melted in a clean, iron ladle. Source of heat should be removed as soon as the alloy is completely melted, at which time it is ready to pour. The solidified casting should be removed from the chamber before, or when, it cools to room temperature. If allowed to remain in the mold over an hour, it will grip the chamber walls and be difficult to remove. Clean the chamber of the rifle thoroughly, then plug the bore immediately ahead of the throat with a small rag - but not so tightly it cannot be driven out. If possible, pour the molten Cerrosafe through a small tube into the bottom of the cast, gradually removing the tube as the chamber fills. If the barrel is cold, warm it to room temperature or above before making the cast. When cooled, remove from chamber, using a rod or dowel from the muzzle end of the gun.

I've used it for a rifle chamber casting. Just as with boolit casting, if the "mould" is cold, the casting will be wrinkled. If you get the barrel too hot, the casting will take a long time to cool and may be difficult to remove. The good part is that since it's a low melting point alloy, it's easy to heat the barrel enough to melt it out if necessary.

Personally, I'd rather use Cerrosafe where the casting can be easily pushed out after it shrinks than to put a rod down the barrel, even a brass one, to pound a lead slug through the bore.

Regards,

Stew

blackthorn
03-01-2011, 12:40 PM
While the makers of Cerrosafe produce several different alloy combinations, the one we are concerned with consists of the following percentages: Bismuth - 42.50%, Lead – 37.70%, Tin – 11.30%, Cadmium – 8.50%. Note: Cadmium is very toxic () so use good hygiene and avoid breathing the fumes. We all know the harmful effects of inhaling or digesting lead. Cadmium is even worse. Its compounds are extremely () toxic even in low concentrations, and will bioaccumulate in organisms and ecosystems. So use similar but even greater caution when working with Cerrosafe as you would when handling lead.

Notes on Cerrosafe:
 Melts between 158 and 190 degrees Fahrenheit
 Should be melted in a clean iron ladle without direct flame on the product.
 The chamber being cast should be cleaned thoroughly and a thin coat of oil or graphite applied.
 Reusable

Contraction - expansion factor versus time, after casting, measured in inches per square inch:
 2 minutes -.0004"
 6 minutes -.0007"
 30 minutes -.0009"
 1 hour +-.0000"
 2 hours +.0016"
 5 hours +.0018"
 7 hours +.0019"
 10 hours +.0019"
 24 hours +.0022"
 96 hours +.0025"
 200 hours +.0025"
 500 hours +.0025"

Basic Instructions:
 Plug the bore about one inch ahead of the throat of the firearm using an appropriate size cleaning patch.
 Pour the molten alloy directly into the chamber until full and allow it to cool; it will turn a shiny silver color. As soon as it has cooled enough that it is no longer a liquid (and doesn't present a burn hazard), run a rod into the bore from the muzzle and tap the casting out of the chamber. Take care not to overfill the chamber as the alloy will then run into the locking lug area, making removal extremely difficult. Any recessed areas can be plugged with modeling clay prior to pouring.
 During the first 30 minutes of cooling Cerrosafe shrinks and then begins to expand. At the end of one hour it should be "exactly" chamber size. The Cerrosafe will manage to find its way into some pretty tight places so it is easier to have the rifle stripped to the frame prior to commencing the job. Clean the chamber, lightly oil it (then wipe it out with a patch), plug the barrel at a point that allows the formation of about an inch of rifling to be included in the cast, and cast it.

Cerrosafe's melting point is below the boiling point of water so you can use a plastic funnel with a short length of vinyl tubing to get it into the chamber. The tubing should be just long enough to reach the chamber with the funnel set through the back of the receiver. Heat the Cerrosafe in a skillet ashtray, or other container with a pouring spout, over a heat source set on low. As soon as the cast has set up, push the ‘plug-patch’ along with the casting out of the receiver with a wooden dowel or brass rod.

There you go! Have a nice day!

mdi
03-01-2011, 12:48 PM
Why is it that we seem to always have a better new idea before trying the tried-and-true old idea? I'm all for new ideas, but good new ideas are born of the need to improve upon existing ones that have proven inadequate somehow. Just slug the freakin' thing already.

Gear
In other words; if it ain't broke keep yer greasy fingers offn' it!:p

mdi
03-01-2011, 12:52 PM
It's basically like pouring a lead lap. The problem is not with the lead sticking in the muzzle (because it won't) but that it will likely be well undersize. Like pouring alloy in a mold that is too cold. You can heat the barrel slightly with a heat gun to get better fillout but chances are that it will still be undersize. A brass rod near bore diameter can be used to drive it through.
O.P. has been getting a lot of ribbing about his question, but I think this is the answer. I've read about hand lapping barrels and the "lap" was made this way...

roysha
03-01-2011, 01:02 PM
Pure lead will NOT stick in the barrel if the barrel is even fairly hot to the touch unless you fill it from one end to the other. Then it is a mechanical obstruction rather than adhesion as in soldering. As several poster noted, that is how a lead lap is made. I defy any of you to solder on a sight with pure lead and no flux.

Back in the late 50s and early 60s when then were a lot of rechambered military rifles of somewhat dubious caliber identification I poured a lot of lead into chambers to at least get an idea of what it was supposed to be. I didn't know about cerrosafe then. The most popular ones were the 8mm-06 and the 7.7-06 but there was also things like 6.5-257 Robt. and an occasional 6.5-06. I never had the least bit of a sticking problem because of the shrinkage of pure lead.

As to measuring with a tenths mike, the majority of the folks here are pretty much stuck with what ever the factories decide to deliver to us and it sure as hell isn't at the accuracy level of tenths. I recently purchased two sizer dies of the same caliber for myself and an acquaintance who is just starting to get serious about casting. Same brand, same caliber, .001 difference between them (.0004 under for one and .0005 over for the other[the marked nominal size]). Fortunately we ordered them undersize for what we wanted so correcting them was not an issue. I have the capabilities and the means to correct/adjust things like that but I doubt most people here do.

Sometimes plans are a little "over speced" and as it relates to sizing cast bullets it can get way "over speced".

As several posters suggested, just use a pure lead slug and mash it in the bore between a couple brass rods and be done with it. Not only has the wheel already been invented but so has the whole dang car.

geargnasher
03-02-2011, 12:16 AM
Well, after all the avatar DID say to have a sadistic day, didn't it? I'm just following the suggestion! :kidding: No harm intended.

Roysha, if a person orders a true, C-clamp style micrometer from an overpriced, rebadged brand from a reloading supplier, that's their own fault if it doesn't happen to read in tenths. Measuring tools (except for fixtures and such) should be purchased from a tool supply company that specializes in the real deal, not Harbor Freight knock-offs. Even Matco or Snap-On will sell you what you need if you can run a truck down. Anyone can own a nice Fowler, Starrett, Brown & Sharpe, or Mitutoyo micrometer if they make a call to the local mechanic's tool peddlers, they'll even meet you on your lunch break if give 'em a call. Expensive, but you know what you're getting when you pay for it.

Gear

Bret4207
03-02-2011, 07:13 AM
Well guys, my point was that Cerro-safe has a learning curve to it and that using an accurate instrument to get accurate readings and knowing how to use it will give much better results than mashing the jaws of a $3.00 Harbor Freight caliper down into the still hot Cerro-safe.

nanuk
03-03-2011, 06:51 AM
A hot lead lap would still need to be bumped up, just like when lapping a bore and the lap wears.... in stead of melting a new one bump up the old one, until you change grit grades.

it SHOULD work for bore slugging

If Mr Goodyear hadn't played with Latex and sulpher, we wouldn't have steel belted radials.

can you imagine driving down a rough gravel road at 50 MPH on wooden wheels?

roysha
03-03-2011, 12:33 PM
And then when they have measured with their B&S or Starrett or Mitutoyu, and read the tenths, (I doubt very many people have the ability to consistently measure to tenths even using a clutch or clicker) what are most people going to do with the information. Nothing! If it measures within a thou of what they expect, assuming they can even read a micrometer, that is where it will stop.

I own some of all three of the above brands plus some of the cheap drek from china and while I would not want to make my living relying on the long term life of the accuracy of the cheapies, they measure right there with my carbide faced B&S mics. If one cannot split the marks to come close enough (for cast bullet purposes) to get at least .0005 then perhaps they should not be trying to use a mic.

All I'm trying to say is that sometimes we become so involved with the minutiae we lose sight of the fun side of the hobby.

btroj
03-03-2011, 01:13 PM
I use a digital caliper to measure my slugs. For ME it is good enough. I feel that if I am off a 1/2 thou it doesn't matter much for my purposes.
BUT the OP asked about using a poured slug to measure bore diameter. I don't think it would work as well due to wrinkles and shrinkage. It also seems ALOT more work to me. Driving a soft slug thru a barrel is pretty easy.
I personally slug very few guns. I try the diameter I think will work then go from there.

This could easily be viewed as a Ford/Chevy argument. Some feel a need for very precise measurements, some don't. No right or wrong as long as we all know what we are getting from our method.

Brad

geargnasher
03-03-2011, 07:04 PM
I would say that some of us, in some instances, REQUIRE very precise measurements when crafting ammo. Most of the time, for most people, it doesn't matter that much. I keep my Fowlers in the reloading room and the good mics at work, and I measured things to the nearest .0002" by guesstimating between the thousandths marks. One day I discovered that that set had a "tenths" vernier. Neither the tools nor I am reliable enough to use it well, so I'd say it's accurate +-.0003.

As far as digital calipers go, some can be fairly consistent, but few are much closer than .0005" either way to reality. As long as you use the same set for boolit and slug measurement, you're likely to be ok. I measured a sized boolit for a fella once who was having leading issues, he swore that it was .4525", and it was .4510" with three different mics of mine. I told him his .452" sizer was undersized and his mic was bent. Come to find out, he was using a bad set of digital calipers. He got a good 0-1" mic, honed the sizer die until his boolits came out just over slug size, and solved the problem. But like they say, if you ain't got a problem you ain't got a problem, right?

Gear

goofyoldfart
03-04-2011, 01:52 AM
I have been an "A" rated, precision, electrically cross trained, multi-crafted Millwright for 25 yrs.[smilie=w: I also have precision Starrett , Mitutoyo, and B&S mikes, stainless dial calipers and indicators that I have from the years of work. a couple of thousand dollars worth.[smilie=s: many decades ago there weren't Harbor Freight cheapies and if you brought the cheapies that you could find on the job, you were ridiculed and not allowed to use them on any thing serious.:shock: Yes, even today with bad eyesight, I can "read between the lines" , But then I was trained to do so. Y'all probably don't need to read to a ten thousandth, but please do remember that some of us can! For us old dogs, that is what they make magnifying glass for.:violin::coffee::coffee:

Bret4207
03-04-2011, 07:51 AM
And then when they have measured with their B&S or Starrett or Mitutoyu, and read the tenths, (I doubt very many people have the ability to consistently measure to tenths even using a clutch or clicker) what are most people going to do with the information. Nothing! If it measures within a thou of what they expect, assuming they can even read a micrometer, that is where it will stop.

I own some of all three of the above brands plus some of the cheap drek from china and while I would not want to make my living relying on the long term life of the accuracy of the cheapies, they measure right there with my carbide faced B&S mics. If one cannot split the marks to come close enough (for cast bullet purposes) to get at least .0005 then perhaps they should not be trying to use a mic.

All I'm trying to say is that sometimes we become so involved with the minutiae we lose sight of the fun side of the hobby.

If you go back and read my post and what it actually says vs what you seem to think I said you'll see I stated that when you want to accurate readings you do it correctly with the right equipment that you know how to use properly. I'm sure you've seen the people that use a mic like a C-clamp or the ones that push so hard on the wheel on the caliper they strip the friction surfaces. I can read between the likes and guess at the tenths too, but for a guy to whom all this is new, that wants an accurate reading, he needs to slug, use the right tools and use them properly. Most people who haven't put any time in with a mic have a hard enough time figuring is the division they are looking at is .025 or .050 much less figuring tenths.

Personally, I only slug when I see a need to slug. But when I do I want to know if it's .3113 or .3117.