leading from too low velocity?

[lylejb]

am working on a very reduced load in 357 cases, for the wife and kids. i'm looking for a little more than a 22, just so they can get some plinking in, without scareing them too bad:wink:

tried several loads today, all with AA#2 powder and a 158gr commercial cast lswc. (yeah, i know... i haven't made the jump yet to cast my own, but the moore i read here the better it looks to me )

the loads were 2.4 gr, 2.6gr, 3.0gr, 3.5gr. i noticed the 2.4 and 2.6 loads both leaded around the throat / forcing cone/ cyl gap area, but not in the barrel. i've fired these same bullets in normal loads 1000 fps or so, with no trace of leading.

the top corner of the frame and forcing cone area looked like it was spray painted silver, but mostly cleaned up when i went to the 3.0gr and higher loads.

does anyone know what happened here? i was always told you get leading from too high of velocity. these were fired in a dan wesson .357 8"

thanks, lyle:confused::???:

[primersp]

sometime commercial casting are very hard and must be handload to high level for seal
the barrel differently ,it's the same that undersized bullets

[GLynn41]

bullet fit is very important when it comes to well about everything -- if the boolit does not slug up because of the pressure of the load then you will get leading regardless of the speed fast or slow

[n.h.schmidt]

Hi
For what you want to do,this will work. Buy some commercial swaged bullets . they are out there and being swaged they are soft. They will slug up better in light loadings. Very hard lead usually dosn't work well in light revolver loads.
n.h.schmidt

[Rocky Raab]

The guys above are correct.

To summarize: Commercial cast bullets are almost always very hard (to ship better, NOT to shoot better!) They can also be undersized, especially for an individual gun that might run a bit large.

Loading to low pressures doesn't provide the force needed to "bump up" or obturate the bullet so it fills the bore, thus allowing hot gasses to squeeze past the bullet. That's the number one cause of leading - especially light load leading.

Your remedial choices include loading those bullets to higher pressures, either for them or reserving those for yourself. Or buying softer swaged bullets for those light loads. Or casting your own both larger and softer (and with better lube than on commercial bullets).

[Larry Gibson]

Concur with above posts. For such loads commercial cast are too hard and the lube is very poor for low end velocity loads. I also suggest a commercial swaged bullet such as Speer and Hornady's for such loads since you are not casting your own yet. I'd suggest either firms 148 gr HBWCs. You might also want to switch to a faster powder such as Bullseye for such loads. In .357 cases use 3 gr and in .38 Special cases use 2.7 gr. Seat the HBWCs so the case mouth covers about half of the front driving band and use a light taper crimp. Both are the "classic" target load and are just about what you are looking for.

Larry Gibson

[zxcvbob]

I use these for my home defense load (with 4.6 grains Unique in .38 Special brass):
http://www.midsouthshooterssupply.com/item.asp?sku=00051515

Should be good anywhere from target-load velocities up to about 1000 fps. And if they don't work for you in light plinking loads, they'll still be useful.

I've cast a bunch of Lee 158-RF boolits using almost pure lead (about 1/2% tin added to get sharp corners) It should be great in .38 Specials, but I haven't gotten around to shooting any yet.

[lylejb]

thank you for all the responses.

now this is starting to add up :idea:

my usual load for my target practice / plinking is about 1000 fps, and i know i've loaded these higher, about 1250 or so, but i hadn't tried light loads before.

if i understand this right: the bullet is too hard, for this low pressure load. Because it's too hard, it doesn't expand to fit the bore, and allows gasses to leak by. this leakage partially cuts into / melts a small amount of lead, which is deposited as leading.

a couple of mentions of the lube. these have a hard, blue wax like lube. i'm guessing that's probably a choice by the caster to help survive shipping. would it help, or be worth it to try more or other types of lube? i dont have a lube sizer, but have read on hear about "pan lube" with a liquid lube. would that be worth trying?

Larry, i know this type of load needs a fast powder, and i did think about bullseye. unfortunatly, i don't have b'eye right now, and haven't seen anyplace that has it in stock (local) for months. AA#2 is the fastest powder Accurate makes. i have a burn rate chart that shows it directly after B'eye. it's faster than red dot and W231, or so the chart says. i have almost a full pound on hand, so that's what i would like to use.

Thanks again for all your help

Lyle

[Larry Gibson]

Lyle

Goes to show there are alwyas differences. The latest "burn rate" chart I have lists 117 powders with Bullseye at #9 and AA#2 at #20. My point in recommending Bullseye is that it is a single based powder and AA#2 is a double based powder. It is a good powder for DEWCs in the .38 Special. Realise that a DEWC in the .38 leaves only a small case capacity. Thus the ignition of the AA#2 is consistant. However, once you go to a HBWC the case capacity dramtically increases. It is even greater with a SWC with much of the bullet seated out of the case. You further increase this case capacity by using the longer .357 case. This is where the much easier to ignite at low pressures single base powder like Bullseye shines.

You can increase the powder charge with AA#2 until it does burn efficiently but then you may be pushing the loads too high for a "little more than a 22, just so they can get some plinking in, without scareing them too bad" load. The real problem is the hard cast bullets with the hard wax lube. With the current powder availability problems I suggest you try the swaged commercial lead HBWC bullets over 3, 3.2 and 3.5 gr of the AA#2 in the .357 cases. If you can't get the commercial HBWCs then try getting some Lee Liquid Alox and tumble lube (leave the hard wax lube on the bullets) those commercial cast bullets per the instructions and try them with the above recommended loads of AA#2.

Larry Gibson

[zxcvbob]

It is a good powder for DEWCs in the .38 Special. Realise that a DEWC in the .38 leaves only a small case capacity. Thus the ignition of the AA#2 is consistant. However, once you go to a HBWC the case capacity dramtically increases. It is even greater with a SWC with much of the bullet seated out of the case. You further increase this case capacity by using the longer .357 case. This is where the much easier to ignite at low pressures single base powder like Bullseye shines.


Bullseye is a double-based powder. In fact, it has more nitroglycerin than any other powder except Power Pistol (about 40%) It is easy to ignite because it is small flakes instead of balls, and it probably doesn't have any deterrent coating.

DEWC and HBWC give you exactly the same case capacity when seated to the same length. The only thing that changes is the shape of the powder chamber.

[lylejb]

again, thank you for your help.
i looked up online a burn rate chart, and your right. the chart i was looking at was older. it looks to me, however, that most of the powders between #9 and #20 simply didn't exist when my older chart was made. i don't think bullseye or AA#2 has changed, just newer competetors have entered the market, that fall somwhere inbetween.

as far as i know, i wasn't having any ignition problems. all loads seemed consistant, among those with the same charge. i don't have a chronograph to check velocities or spreads.

for these loads, i do seat the bullet front drive band flush with case mouth. this is a trick from Accurate's cowboy action data. this decreases case volume to approx 38 special.

as i said earlier, i don't have any b'eye, and haven't been able to find any locally in months. i did think about it, and if i had it, i would use it. i do think the AA#2 is fast enough for what i'm trying to do.

another part of my interest is to use as much of what i have on hand as possible. all loading componets have been few and far between in my area, and even if i could find a mail order / online place with powder, it wouldn't be worth the haz mat +shipping for only a can or two.

i have about 500 - 600 of these bullets left. i'll try the alox (if i can find that) on a hundred and see if that helps.

thanks again for all your help

Lyle.

[Rocky Raab]

Lyle, AA#2 is just fine. I just shot a box of 38 Specials loaded with it a day or three ago. A 158 SWCL over 4.0 AA#2 gives me dead at 800 fps and is accurate enough to consistently hit a gallon jug at 100 Yards, offhand. Fine load.

[Larry Gibson]

lylejb

Yes there certainly have been a lot of new powders the last few years. I do stand corrected by zxcvbob wherein Bulleseye is a flake double based powder. I don't know how I missed that mistake. However the point he also makes is that it does ignite much easier. You may or may not have had ignition problems as mentioned but poor and erratic ignition also can cause the gas blow by and leading as you describe. Also since you were apparently wanting some "little more than .22" loads the level of pressure may not have been sufficient for efficient ignition. Then again it may have but since you didn't chronograph we don't know so it was just another consideration. My bet is the LLA tumbled bullets with your 3 or 3.5 gr loads of AA#@ will lead very little if at all. Let us know what happens.

Larry Gibson

[lylejb]

the good news....i scored a can of trail boss, the one and only can of powder my local bi-mart had[smilie=w:

the bad news, i cant find any lee liquid alox. i've checked all the usual places, and called around. no one local has any left, or has any idea when they may get more (of course):roll:

i'm going to go with 2.7 gr of trail boss, the min starting load for 38 sp, and see how that goes.

does anyone have any ideas for tumble lube other than LLA.

does any member here sell a similar product to LLA?

Thanks

lyle

[zxcvbob]

the bad news, i cant find any lee liquid alox. i've checked all the usual places, and called around. no one local has any left, or has any idea when they may get more (of course)
i'm going to go with 2.7 gr of trail boss, the min starting load for 38 sp, and see how that goes. does anyone have any ideas for tumble lube other than LLA.
For low-velocity loads, I like Rooster Jacket better than LLA. You might can find some of that; I think Midway has it. I've also heard of using Johnsons Paste Wax for boolit lube. The usual way is to heat them up then slosh around in a plastic ice cream carton with a small dollop of JPW. But it would probably work to thin the wax with turpentine and use just like LLA. (I haven't tried using paste wax, just read about it and I made up the turpentine part)

[wallenba]

If the barrel is clean, but the throat and cone have buildup I'd suspect the bullet may be 'shaving'. The cylinder may not be parking square with the barrel. It would not take much. Get a lewis lead cleaner kit, it has a special cone insert w/ brass mesh to clean that stubborn stuff out, then get it looked at. Shaving can be dangerous to bystanders as a small chunk can get blown sideways.

[Rocky Raab]

I'll second the Johnsons Paste Wax. Perfectly adequate bullet lube for low to medium-speed loads in handgun and rifle.

You can melt in in a tuna can, hold the bullet by the nose (I use big tweezers) and hold it in the wax for four to five seconds - enough to warm the bullet a bit and get a nice thin coat of wax. Cold bullets come out with a thick goopey coating. Stand the bullets on their bases on wax paper and allow to completely dry and cool. The solvents in the wax have to evaporate, just like from LLA. Overnight is enough, usually.

With either JPW or LLA, I like to dust the bullets with powdered mica to get rid of the sticky tacky feeling. It might even add some lube quality.

[lylejb]

Finally got some shooting time:)

as i said earlier, i now have trail boss powder to work with, and am very happy with the results.

i tried 2.4gr and 2.7 gr , both loaded in 357 cases with 158swc commercial cast.

my leading problem is about 99% gone. Just a trace at the flat edge of the barrel, where the forcing cone starts. [smilie=w:

thank you to all that helped.

special thanks to Larry Gibson, your suggestion of a faster powder was what i needed. I still can't find any bullseye locally, but the trail boss is working well for me now.

i still haven't tried changing lubes. I'll probably try JPW as i can get that easily, just to see what happens.

THANKS AGAIN TO ALL, FOR YOUR GENEROUS HELP.

LB