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mallen
09-12-2014, 09:44 AM
Will 9mm @ .356 work with 20 to 1 lead, bhn 10?

Sgtonory
09-12-2014, 09:47 AM
Yes I use around 9 bhn for 9mm. But I have to use a Lyman m die for 38 special. And make sure my case doesn't swage down the boolit.

mallen
09-12-2014, 10:05 AM
Yes I use around 9 bhn for 9mm. But I have to use a Lyman m die for 38 special. And make sure my case doesn't swage down the boolit.

If that's the case, then I could even go 30 to 1. Although, i'm not really sure what lead i'm starting with. I'm adding pewter that i'm told is 97 tin 3 antimony.

mallen
09-12-2014, 10:11 AM
Side question.

lets say i don't have an issue with leadding for whatever reason, how much tin would i need, simply to make the lead fill out the mold?

thanks

Garyshome
09-12-2014, 10:34 AM
That's about what I use.

Rizzo
09-12-2014, 12:36 PM
The .356" bullet seems a bit small from what I've read around here. .358" seems to be the norm.
A lot of casters "slug" their barrel to find out what they should be using.
.001-.002" over that barrel "groove" measurement is also the "norm".

Regarding the bullet hardness, going down the "technical" road of bullet obturation vs psi the 9mm can get pressures up to 30,000+ psi and at that pressure you should "technically" be at a BHN of 25 or so.
However, a lot of casters using BHN of 12 or so with 9mm do not have leading problems so you can't argue with success I guess.
Just passing along what I have read/learned here.

runfiverun
09-12-2014, 12:55 PM
I'd be more concerned with the 356 diameter than the 20-1 alloy.
however I have found that even with a 358 diameter, my 9m's preferred a slightly harder alloy than plain ww's.
I add a little lino to mine, 8-1 is where i ended up.

how much or how little tin you add depends on a couple of things, mold temp/design is the main influence, venting [how you pour], alloy temp, and head pressure of the pot or ladle will all influence the need for tin in your alloy.

montana_charlie
09-12-2014, 01:09 PM
Will 9mm @ .356 work with 20 to 1 lead, bhn 10?
I know what the published charts say, but if you are dealing with 20-1 alloy made from certified ingredients, the hardness is 7.8 BHN.

CM

tazman
09-12-2014, 06:51 PM
A lot of the success depends on the design of your particular barrel. Barrels with taller and wider lands grip the boolit better than narrow short lands. You can improve the grip somewhat with harder alloy but there are limits to this. With a good barrel you can get by with softer alloy.
I had problems with my Taurus PT92 stock barrel not grouping with cast. I changed to a Beretta barrel with wider taller lands and now it groups like a champ.

Echo
09-12-2014, 07:16 PM
Fillout usually only requires about 3% as a maximum, or so I hear. As others, I'm concerned about the .356 number. Better slug the bbl to make sure . . .

zomby woof
09-12-2014, 07:57 PM
I have EAA Witness in 9mm for 14 years. I've shot commercial 9mm lead through it and it leads like crazy. It turns out it has a .357" barrel. All the commercial was .356". I recently ran some LEE 356-120 sized at .358 with rifle alloy. I also coat with HI-TEK. I have no more leading.

MtGun44
09-12-2014, 09:51 PM
100% what r5r said. Diam is too small, hardness may be just fine, most of the
time I care not what hardness I use for pistols. I suggest .357 or .358 are more
likely to work without leading or tumbling, both problems that are extremely
common with the 9mm Luger cartridge.

Bill

mallen
09-13-2014, 06:43 PM
ok. im a bit confused then. the technical spechs of 9mm is .355. my barrel slugs at .354 (iv done it several times). and my mold is a .356. many people have said that im supposed to be .001 above the slug. in which case, .356 bullets are .002 above. I still lead.

runfiverun
09-13-2014, 09:29 PM
technical speccs HA,,,,,,HA,ha ha ahhahh.
welcome to the real world..

check your non existent throat...
your cutting the boolit going into the barrel.

Shiloh
09-14-2014, 08:59 AM
Will 9mm @ .356 work with 20 to 1 lead, bhn 10?

No bullets sized that small, with ANY alloy. would work with accuracy in mine. They would pattern at 50'.
I have tried very hard lead. No luck.

Shiloh

mallen
09-14-2014, 10:51 AM
technical speccs HA,,,,,,HA,ha ha ahhahh.
welcome to the real world..

check your non existent throat...
your cutting the boolit going into the barrel.
I have a question about the throat. I have been basing my slug based on the muzzle. im told the barrel should not taper. but i swear that it is tapering, if i slug just to the throat and push it back out it clearly slugs bigger than at the muzzle.

could this be why im getting the leadding?

runfiverun
09-14-2014, 12:42 PM
that is the correct direction for a taper, and it's usually a good thing.
what is bad is if there is a tight spot somewhere in there leading you to think there is a taper.
the tight spot will squeeze the boolit down, then allow gas to blow by after it passes.
the blow by can/will cut the boolit, and the smaller boolit will lose grip on the rifling....

MtGun44
09-14-2014, 07:30 PM
The Lee 356 120 TC is STRONGLY RECOMMENDED, it will feed and chamber
in most guns, even those with little or no throat, and has a long area to engage
rifling. Conventional lube recommended, too. Many guns have chambering probs
with RN designs due to the throat issues mentioned. Will reiterate:

USE THE LEE 120 TC conventional lube at .357 or .358 for shortest route to success.

Hardness is a tertiary issue, with fit #1, needing a LARGER than groove diam boolit
in most situations. Lube is #2, IMO. Recommend NRA 50-50 or any of the many
copies. LBT soft blue is also excellent.

Have to, again, agree 100% with r5r - on the "specs" -- means zip, specs are 1st,
for jbullets, and second - irrelevant to reality. Fact is, .355 will not work in 50-60% or higher
of 9mms. If you would like to verify that for the umpteen thousandth time, have at it.
All we are offering is the predicted 'short cut to success'. Did I mention the Lee 120 TC? :kidding:

Bill

Harter66
09-14-2014, 07:39 PM
Question? Has this pistol launched a lot of 147s ? I had 1 once that had had in a former life probably fired a bunch of heavies. The result was that the center length of the bbl fouled while the first and last quarter of the bbl. The bbl was by all measurable means about .002 bigger at its midpoint and under size at the muzzle by .001 of nominal. I fire lapped and removed the breach end "hump" and that also bought the muzzle up to the skinny side of nominal.

mallen
09-15-2014, 12:44 AM
The Lee 356 120 TC is STRONGLY RECOMMENDED, it will feed and chamber
in most guns, even those with little or no throat, and has a long area to engage
rifling. Conventional lube recommended, too. Many guns have chambering probs
with RN designs due to the throat issues mentioned. Will reiterate:

USE THE LEE 120 TC conventional lube at .357 or .358 for shortest route to success.

Hardness is a tertiary issue, with fit #1, needing a LARGER than groove diam boolit
in most situations. Lube is #2, IMO. Recommend NRA 50-50 or any of the many
copies. LBT soft blue is also excellent.

Have to, again, agree 100% with r5r - on the "specs" -- means zip, specs are 1st,
for jbullets, and second - irrelevant to reality. Fact is, .355 will not work in 50-60% or higher
of 9mms. If you would like to verify that for the umpteen thousandth time, have at it.
All we are offering is the predicted 'short cut to success'. Did I mention the Lee 120 TC? :kidding:

Bill

I know what you mean about tech spechs. I only asked about that for more understanding. Now that im adding tin, the mold is filling out much better and im getting a good 1 to 2 thousand larger than my slug.

Well. I tried 99 rounds of the powder coat with a good thick coat. just soft range lead. didnt take much cleaning and the bore was good and clean. looking at it close tho, there is kind of a texture to it, a pitting almost. im not sure if iv done something to the barrel, or if iv just never really looked at it that close. (i don't think iv ever shot any 147 gn in it, someone asked). My last batch iv been making 20 to 1. sure fills the mold much much better. looks more metalic as well. that should make them run perfect without the cost of adding more pewter.


went to the flea market today. only found one piece of pewter. wasnt even worth buying.


im trading a guy some wheel weight lead for rounds. 750 rounds for 30 lbs (he is also trading 1k of these iv got now for primers). im excited about that. should have 3% antimony, so i can add 3% of my pewter tin and have electrotype. 12 harness. should be able to hit modest velocities for 9mm without powder coating. much faster with powder coating. If i am understanding all of this correctly.


thanks for all the help.

mallen
09-15-2014, 12:55 AM
as far as lube goes, that is what the powder coat does, but if i can do it right and afford it, i could use something else and not powder coat. iv thought about doing the 45/45/10 iv read about. obviously i can get the lee stuff a try and see what results i get. the lee liquid alox sucks. a lot.

as far as size. im stuck with .356 as that is what my mold makes.

although, solid black bullets do look kinda sexy. not to mention the glow in the dark powder coat.