loads too hot? 357 reloading

[Rock_Steady]

I am trying some lil' gun in my .357 reloads and I'm wondering if I'm trying to push too fast. I put 18.0 gr Lil Gun behind a 158 gr LSWC with a CCI small pistol primer. I have no chrono, but from the gun's reaction I'm thinking this is putting me too fast. Anyone have thier own experiences/loads for using lil gun to push lead?

 

[Brian Williams]

I love that load in my 1894C Marlin. I have no signs of pressure or bulging. I was looking to find out if anybody was shooting this load in a revolver, particularly a S&W K or L frame.

 

[Rock_Steady]

How about leading? Ever have any problems? It just seems that I'd HAVE to be going way over 1000 fps and causing some build-up.

 

[JackOfAllTradesMasterAtNone]

It depends... Are you shooting a light framed revolver or a Ruger Blackhawk?

There are other signs to look for concerning pressure buildup. First, I'd figure you should be using a small magnum primer. I'd have to look at the book to be sure though. I've never loaded that powder before, but one sure sign is if there are any remaining flakes of powder left in the case once fired. Also look at the shell/case base. Is it flattening? Is the primer flattened? Is it difficult to extract the case from the cylinder? I once broke the frame lock on a Taurus 66 (same as a Smith), by shooting hot loads that functioned fine in a lever action rifle. -Then to find out the screws where coming loose on the rifle with those loads of 296 powder.

One of the best things I ever bought was a Shooting Chrony.

-Steve

 

[The Bushmaster]

Don't look for flattened primers as half of my firearms flatten primers. Instead look for cratered or blown out (sooty) primers. Hard to eject. Ballooned or split cases.

 

[Johnny Guest]

Rather too warm for lead

Rock, may I ask where you got that load? I do hope you have at least a couple of good loading manuals. They'll provide you with alternative loads.

According to the Hodgdon loading information on their website, 18.0 gr. of Lil' Gun is MAXIMUM load for the XTP 158 gr bullet. They say it gives 1577 fps in a ten-inch barrel. Check at - - http://www.hodgdon.com/data/pistol/357mag.php

You don't say what particular lead bullet you're using, but it would need to be terribly hard NOT to lead at such a velocity. I doubt the pressures would be greatly excessive for the first few rounds. I'd bet, though, that at such speeds the lead bullets will be leaving a lot of lead deposits, which can really run the pressures up.

Unless you're using a very long barrel, It's as pretty good bet that lead bullets are stripping and exit the muzzle without properly stbilizing. That being the case, the accuracy will be very poor even before leading causes it to go very bad.

If you want to load at top velocities, I suggest you invest in some jacketed bullets, back down a full two (2.0) grains, and work up a bit at a time. I bet you'll decide to stop before you reach the full max.

If you really want to shoot up those led bullets, You might want to purchase some other powder.

Best of luck
Johnny

 

[Rock_Steady]

oops - I did forget to say that I'm shooting from a 1894c marlin lever action carbine.

Also, I'm not seeing any pressure problems or degradation in my accuracy - I can just definitely tell that I've got a warm load in there.

They didn't post any minimum loads, and I worry about squibs. The primer pocket does not seem bulged, I'm having no problem with case extraction - although sometimes with winchester brass I have problems chambering the next round - still trying to figure that one out.

I'll try backing off about 2-3 grains and see what happens.

Also, I'm using the laser-cast 158 gr LSWC.

--Rock

--Edited for operator headspace and timing.

 

[bouis]

I'm kind of a newbie loading .357 mag (at least with "magnum" powders & primers) and I'm seeing flat primers with 5% below listed max loads. Gun is a Python with a 6" barrel.

16.8 grains of 2400 and a Winchester SP Magnum primer under a 125 grain Remington JHP gives flattening primers. Not too hard to eject the cases, but they don't just fall out like, for example, the Remington UMC factory ammo does. The UMC seems to be just as hot a load, but without the pressure signs.

For example the Lyman manual gives 17.7 gr as the max.

I only shot a couple rounds -- are these pressure symptoms something I should be worried about?

Edit: pics, load above on left, unfired UMC on right for comparison.

 

[Ol` Joe]

I don`t put much faith in primer appearance anymore, in pistol loads especially.
Concider. The primer is built to work in all cartridges that use that size primer. A large pistol primer for example has to ignite a 44 magnum round and hold back the resulting pressure the same way as it does when used in a 45acp. The primer can not be expected to show flatting with high pressures in a 45 acp when pressure excedes the 21000psi max and not totally flatten from the 36000 psi working pressure of the 44.
Now primer blow by, sticky extraction, excessive velocity for the charge (if you have a crony) can mean pressure is too high. Stay with the books suggested loads and you should be OK. I doubt with a load 5% under max your flat primers are caused by anything but the primer being pushed out of the pocket on ignition and haveing the case move back as pressure rises and reseating it. This will cause flattening and is common in low pressure rifle loads. It usually also will show as soot on the case body for 1/2 or so way down as the case/chamber isn`t well sealed until pressure rises enough to expand it fully against the chamber wall.

 

[Clark]

CAUTION: The following post includes loading data beyond currently published maximums for this cartridge. USE AT YOUR OWN RISK. Neither the writer, The High Road, nor the staff of THR assume any liability for any damage or injury resulting from use of this information.


*1950's vintage Colt Police Positive 38 Special 4" barrel, that I reamed the chambers out to 357 mag:
1) 18 gr. LIL'GUN 158 gr. XTP 1.59", WSPM, 1173 fps [Hodgdon max load]
3) 23.5 gr. LIL'GUN 158 gr. XTP 1.59", WSPM, 1155 fps


I wrote Hodgdon and asked why they stopped at 18 gr a 25kpsi, and they said that was all the powder they could fit in the case.
I asked them why not use the 158 gr LSWC, and they said that LIL'GUN was melting the bottom of the bullet. [But I don't have any trouble with 18 to 26 gr of LIL'GUN with 158 gr LSWC generic lead bullets.]

What I found was that more LIL'GUN past 18 gr just makes the revolver kick harder, make more noise, and more peak pressure. The chrono was not impressed. I was impressed with the high velocity at low pressures. I can get a 158 gr moving faster than that with a .380 and Power Pistol, but my 380 can take much more pressure than my .357 mag.

Looking at the Hodgdon data:
http://www.hodgdon.com/data/pistol/357mag.php

158 GR. HDY XTP COL: 1.580"

H110 16.7 gr 1591 fps 40,700 CUP
LIL'GUN 18.0 gr 1577 fps 25,800 CUP


Someone on the internet has pointed out to me that the Hodgdon 158 gr data is bogus, and that H110 is just as good.



What does it all mean?
I think I am going to switch back from LIL'GUN to H110, becuase it smells better.

 

[Grump]

I'm not too keen on relying on primer "flattening" to estimate pressures below 35,000 PSI (9mm P max, IIRC).

The primer pocket does not seem bulged

You can't tell that without trying to seat a new primer. If they go in with hardly any resistance (especially compared with once-fired brass), there IS a problem SOMEWHERE, which could include overpressures which I believe would be somewhere above 65,000 PSI.

bouis wrote:

16.8 grains of 2400 and a Winchester SP Magnum primer under a 125 grain Remington JHP gives flattening primers.

Well, what you have pictured is LESS flat than what I've gotten with Federal [edit typo!] 125-gr .357 loads.

The problem with trying to "read" primers is that it is highly affected by headspace and the type of case stick/slide/stretch that happens in YOUR chamber. For example, one rifle I have will show what looks like overpressure flattened primers with normal loads, if I let my sizing dies crunch down to minimum ammo headspace. What happens is the primer backs out early in the firing cycle, then the normal case stretch/slide whatever as the casehead finally impacts the bolt face mushrooms that primer in the pocket. Lighter loads leave the case stuck forward in the slightly loose chamber, with the dreaded "primers backing out" pressure "sign."

I've seen an article in Handloader magazine that showed "normal' looking primers in rifle cartridges, from loads which were proven to be overpressure by other methods. "Reading" primers is very inexact and must be corrected for variables of your gun.

Carefully reading the squaring off of the radius of a primer in lower-pressure rounds (21,000 PSI and less) like .45 ACP and .38 Special, might be possible if you carefully compare with factory loads using the same primer....maybe...

 

[Jim Watson]

Oh, dear.
"They didn't post any minimum loads..."
But they (Hodgdon) DO post:
"The loads shown here are at maximum. Reduce them by 10% and work up to the load that works best for you. NEVER EXCEED THE LISTED LOADS"

 

[Rock_Steady]

Sorry, I must have committed the cardinal sin. I'll give some of those a look again.

Or maybe just stick to Unique or Bullseye, which seem to have alternate starting points listed for us illiterates.

 

[BluesBear]

I keep hearing so many people moan and groan about possible leading with high velocity loads. As if velocity isd a bad thing.
Leading is caused by so many other things than velocity.

Such as what kind of bullet lube is used? Many commercial casters and most hobby casters get by with the cheapest recycled Criscocrapola they can find.

Also;
What is the diameter of the bullet?
What is the alloy of the bullet?
Is it a bevel base or a flat base or a gas check design?

All of the above can cause leading if not just right.

Shooting a cast bullet that's too small for the cylinder throats can cause leading.
Shooting a cast bullet that's too small for the bore can cause leading.
Shooting a cast bullet that's too large for the bore can cause leading.
Shooting a cast bullet with an improper base can cause leading.
Shooting a cast bullet that's too hard can often cause more leading leading than shooting one that's too soft.


A cast bullet needs to obturate enough to properly seal the cylinder/bore.

Anything that causes the propellant gasses to slip past the bullet base will cause leading.

For instance a soft bevel base bullet may load easier but it's also more likely to suffer gas cutting (leading) on the base than a similar flat base design.

Same for a hard cast bullet that is undersized for the bore/cylinder. Gas cutting will once again cause excessive leading.

A grossly oversized bullet with Criscocrappola lube will lead excessively because it must squeeze itself through the bore.

And shooting a gas-check design without a gas check is just asking for gas cutting.

And we haven't even discussed lube/powder smut that is commonly mistaken for leading.


Velocity is only a small part of the equation.