HP-38 strange fouling

[Steve C]

While I have not used HP38 I have loaded a lot with W231 which is supposedly the same powder.. I have never noticed any powder remnants like you describe with W231 even in 3.1gr .38 spl 148gr HBWC loads. Now generally I load 158gr lead bullets and use 4.5gr for a standard equivalent load and 4.7gr for +p so the pressures are at full power for standard loads and produce velocities from a 4" revolver over the chrono equal to what Winchester lists for their ammo in their catalog.

From your description it almost sounds like what you see when you get slight contamination from lubricant in the powder. Are you using lube on your dies or cases that may be getting into the powder?

 

[ArchAngelCD]

I have a bunch of 158gr JHP that I can try out. The extra weight and the jacket resistance could help. I also have some 110gr JHP freebies. How big of a deal is the published COAL? I feel pretty safe if Im within a couple thousandths of the published number, but is pushing in the bullet another 10th of an inch going to be a big deal? I do have a decent safety margin because the only gun these will go in is a 357. I guess what Im getting at is there any reasonable way to estimate how changing the case volume will affect pressure and how I could safely change the powder charge to compensate?

The SAAMI pressure limits for the .38 Special 17,000 psi, for the .357 Magnum it's 35,000 psi. You have more than enough margin but you don't want to have hot loads around because they always seem to find their way into a gun the shouldn't be in.

As for OAL, in the .38 Special the number in the book is almost useless to you except to tell you what they used. In revolver cartridges you are supposed to use the manufacturer's supplied crimp groove, that is the correct spot to crimp that bullet. Seating depth will effect pressure more in a short cartridge like the .380 ACP than the .38 Special.

 

[washambala]

Are you using lube on your dies or cases that may be getting into the powder?

The dies were cleaned with acetone when I first got them to get the preservative oil off. Cases are not lubed. Supposedly the TiN coating on the die works like a carbide die. I havent had a case get stuck yet. Other than that, I dont see any points of contamination unless it came that way. I could always open up another can and see what I get.

You have more than enough margin but you don't want to have hot loads around because they always seem to find their way into a gun the shouldn't be in.

As for OAL, in the .38 Special the number in the book is almost useless to you except to tell you what they used.

I can give the cowboy bullets a try seated all the way down like you described earlier with a heavy crimp. Ill try backing off the charge a little with those too. Im going to make up some of the jacketed ones too to see if I have any better luck with them. If I load anything that I think might be over pressure, it will all be shot at the next range trip. Ill report back some results hopefully by next week.

Im assuming no one has done any kind of testing that showed "X.Xgr of XYZ powder with an internal case volume of ABC behaves almost the same as the same bullet with .5gr less and a smaller internal case volume. Seems like a table of numbers like that would be pretty useful.

 

[Jim Watson]

The "yellow crumbs" are unburnt granules of powder with the glazing blown off. You are looking at naked nitrocellulose... with about 10% nitroglycerine as is common in Ball powder.

Commonly seen with too light a load... or too much airspace.
The wadcutter should be seated flush with the case mouth. I have loaded a lot of Speer wadcutters with 3.2 gr W231 or HP38 and see some but not a lot of unburnt "crumbs."

I don't know where to seat that waffle weave Hornady 140, but if it is too long OAL, it will leave too much airspace and the burn will be poor. I would seat them down to the top of the waffled bearing surface and see what happened. 4.6 gr HP38 ought to do ok like that.

Only bullet I have ever stuck in the barrel was a 125 at 158 OAL with 4.3 gr HP38. Coming up from low ready the powder was flung against the base of the bullet and it was just too far from the primer to ignite.

 

[washambala]

You are looking at naked nitrocellulose... with about 10% nitroglycerine as is common in Ball powder.

Thats sort of what I was guessing. I just wasnt expecting to see a problem like that with by the book data. It also threw me off because there are thousands of pages of reloading Q&A on forums and other websites, and I couldnt find any mention of it at all.

Even the hornady HBWC data calls for it to stick out of the case about .10" and crimped into the waffle.

 

[Jim Watson]

I have not used Hornady wadcutters.
Most of my wadcutters were Speers, seated flush.
I have a S&W Model 52 midrange .38 only, its wadcutters MUST be seated flush.
Like factory loads.

 

[ArchAngelCD]

From my experience swagged WC bullets like those should be seated flush with the case mouth whereas Cast DEWC bullets are crimped into the crimp groove that is just off the end of the bullet.

 

[Reefinmike]

While I have not used HP38 I have loaded a lot with W231 which is supposedly the same powder.. I have never noticed any powder remnants like you describe with W231 even in 3.1gr .38 spl 148gr HBWC loads. Now generally I load 158gr lead bullets and use 4.5gr for a standard equivalent load and 4.7gr for +p so the pressures are at full power

You have never seen the unburnt powder fouling because you aren't at a low enough pressure to see it. Your wadcutter loads are light but the deep seating depth will get that powder to burn clean. If you really want to see what we are talking about, load up some of those 158gr bullets with 3.2 or 3.4gr of powder. Shoot them and carefully pull out the spent case then tap it upside down on the bench. It is not contaminated powder, it is nekked hp38 with the graphite coating flashed off due to low pressure.

 

[washambala]

I have a S&W Model 52 midrange .38 only, its wadcutters MUST be seated flush.
Like factory loads.

I've heard enough stories about these to strongly consider buying one if I ever found one in the wild, whether I could afford it or not. After I burn up the 100 or so WC loads I have now, Ill try making some seated flush with the case rolled over the top like that. I never had a chance to look at factory HBWC loads up close. I remember seeing a box of S&B in a store once. they wanted almost $30 for it. I didnt even bother to look in the box at that price.

 

[Rule3]

The "yellow crumbs" are unburnt granules of powder with the glazing blown off. You are looking at naked nitrocellulose... with about 10% nitroglycerine as is common in Ball powder.

Commonly seen with too light a load... or too much airspace.
The wadcutter should be seated flush with the case mouth. I have loaded a lot of Speer wadcutters with 3.2 gr W231 or HP38 and see some but not a lot of unburnt "crumbs."

I don't know where to seat that waffle weave Hornady 140, but if it is too long OAL, it will leave too much airspace and the burn will be poor. I would seat them down to the top of the waffled bearing surface and see what happened. 4.6 gr HP38 ought to do ok like that.

Only bullet I have ever stuck in the barrel was a 125 at 158 OAL with 4.3 gr HP38. Coming up from low ready the powder was flung against the base of the bullet and it was just too far from the primer to ignite.

I do believe Mr Watson has it

I recall another thread on this but am too lazy to search for it.

 

[blarby]

Classic sign of too little pressure to burn clean.

This got answered a long time ago !

 

[washambala]

I did a quick search, but without knowing why it was happening, it was hard to get anything useful. Even on the google searcher.

Seating depth will effect pressure more in a short cartridge like the .380 ACP than the .38 Special.

For shorter cartridges like this, how tight should the seating depth be held? Is .002-.003" either way going to make any noticeable difference?

 

[blarby]

Is .002-.003" either way going to make any noticeable difference?

You might notice .02 to -.02,(4 Hundredths) but not in the thousandths.

Most folks (and im not saying you, just most folks) cant accurately measure .001 increments anyway these days as most digital calipers round to the .001th, making accurate adjustments at that level of tolerances fairly moot anyway.

Just work hotter charges. Im sure as you approach maximum loads your cartridge residue should clear right up.

Different powders do have more/different efficient working pressure bands. No two are alike. Most powders burn more cleanly at higher pressures, as the propellant is burned more efficiently via higher temperature.

 

[washambala]

Most folks (and im not saying you, just most folks) cant accurately measure .001 increments anyway these days as most digital calipers round to the .001th, making accurate adjustments at that level of tolerances fairly moot anyway.

I can make measurements that tight. The problem I had with 380 was that if I use the conical seater plug, the bullets arent consistent enough in the shape of ogive to give me exactly the same COL. I can use the flat seater to get better consistency, but then the bullets seat a little crooked.

 

[blarby]

The problem I had with 380 was that if I use the conical seater plug, the bullets arent consistent enough in the shape of ogive to give me exactly the same COL. I can use the flat seater to get better consistency, but then the bullets seat a little crooked.

A not uncommon problem.

You can have custom stems ground from stock stems by most manufacturers, or you can use the FIMO/hot glue trick to make infinitely variable seating stems on the fly without a mill.

 

[washambala]

Ill have to try that. Thanks blarby. If I do that, is there any easy way to get the glue blob out if I get different bullets?

 

[blarby]

Absolutely.

Just pick it off

Hot glue doesn't "bond" to steel. Just sticks.

 

[washambala]

Thats easy enough on a flat piece of metal. Sometimes the stuff likes to hang on when theres a cavity for it to hang on to.

Range report:
I loaded up a ladder of HP-38 loads under 140gr "cowboy" bullets and under 158gr JHP. All of these were loaded with a heavy crimp. The yellow, unburnt powder issue never completely goes away, but the higher loads seems to help. The JHP loads seem to work better. At 4.6gr and at 4.9 (listed as +P in Hornadys data) there is a lot less yellow flaky crap. The lead bullets were not as clean as with the JHP even .2gr above their max load given by Hodgdon (strangely, that same load is .5gr lower than Hornady's max. But Hornady also thinks that HP38 and 231 are different powders and only slightly similar on the burn rate chart....). Even with all the unburnt powder at lower and medium levels, they are less smoky than whatever remington is using in their factory 130gr fmj loads. That smoke makes me gag. It might be better to just get used to the unburnt powder.