Playing around with a new 357 Mag load

[Dumpstick]

Got a new mold, a NOE TL358-175RF, 4 cavity. Cast some last week and decided to load some up today.
Trying a new load, I've never loaded heavy 357 before. These dropped at about 182gr with the alloy I used.

11.6gr Accurate #9, CCI 550 (magnum) primers, PMC once-fired brass. 1.600" OAL. Tumble-lubed with a version of BLL (Ben's Liquid Lube).
I'm expecting around 1050 FPS from this load. We'll see. I'll chrono the load when I get a chance.

I only loaded 48 rounds - 8 cylinders. I figure 4 cylinders to chrono, and 4 to shoot for groups.

If these go well, I want to try a 200gr load, in both .38 Spl and .357 Mag.

Quick shot of my reloading bench. After years of loading, one would think I would have a larger work area, but I use what is available - I think it's 23" wide.

For those that care, I love the Lee Classic Turret. It's compact, and it works.
I can easily load 150+ per hour, starting with tumbled brass. The Safety-Prime system works fine.

 

[Calamity Jake]

So why don't you setup the chrono to shoot groups and chrono at the same time?
That way you get the speed of every shot.
I've don it quite often.

 

[gerhard1]

What revolver are you using?

 

[Dumpstick]

When I chrono, I can't concentrate on groups enough to shoot well. I'm too concerned with not shooting the chrono.
I've been doing it enough, it shouldn't bother me, but I suppose it's a mental tic.

The revolver hasn't been decided yet. Between a 4" Ruger Security Six, and an unfired 6.5" Ruger Blackhawk.

Was going to fire these tomorrow morning, but I'm self-employed, and there's revenue to be generated....

 

[Dumpstick]

Okay folks, since everyone is interested, I figured I'd report on this load.

I went out and fired this new load this morning. Only fired 18 rounds.

The good - the load FEELS good. I fired it in a much-carried 4" Security Six with Pachy Presentation grips. It felt good.
- Primers, while somewhat flattened, showed no signs of stress. No firing pin cratering, the edges were still a bit rounded. Empties fell freely out.
- Accuracy was good, at least for a while.... more on that.... it shows promise.

The bad - These wouldn't even chamber in my GP-100. I know, I'm an idiot for not checking beforehand. I sized these to .358, which presented no problem in the Security-Six.
- Velocity was a bit higher than I wanted. The chrono was fighting me, it didn't want to sync with my phone, but the best I could tell I was getting about 1125 fps. From a 4" barrel. I need to back off some.

The ugly - Leading. By the 3rd cylinder, the rounds started tumbling although accuracy was still good. I looked at the barrel - the last inch or so is leaded to where the rifling is not visible. No lube star on the muzzle. This indicates, to me, that I'm running out of lube.

The plan - clean the barrel. Ugh.
- Break down the rest of the rounds. This is why we only load up a few on a new load. I know better. I'm blaming it on the new Lee Classic Turret press. Once I get in the groove, I just keep going.....
- Re-size the projectiles to .357, and put more lube on them.
- Reload, backing off a half-grain on the charge.

This is called 'working up a load." We do this for fun, right ? Including scrubbing the barrel......

 

[Dumpstick]

Well, I'm back on this. Cleaned up the lead in the barrel - wasn't as bad as I thought. I wrapped a patch around a worn brush, and wrapped some Chore-Boy copper around the patch. A few strokes, it was gone. I'm not certain it wasn't mostly Antimony streaking.

I went and pulled the 30 remaining rounds, sized to .357, and re-applied the BLL ( a tad thicker this time). Reloaded with 11gr AA#9 (instead of 11.6).
These rounds still won't chamber in my GP100.
They chamber fine in every other 357 I own, including a S&W 640-1 (no, I have no plans of firing these out of that little flower.... well, maybe a cylinder full, when I gt this load ironed out...), and a Taurus 669.
I'm thinking this is a function of that particular revolver having trouble with the nose profile of this big RF projectile. I'll drop some pin gauges in the chambers to check, I'm betting the chambers will need to be honed. However, that's a rabbit hole best left for another time.
I think re-sizing was a waste of time.

Went and fired them last week. I would have reported earlier, but everyone had ENS on their mind. Alot went un-noticed, I think.

Here's the numbers, from a 4" Ruger Security Six. I fired 18 rounds for the chrono, which was 10' in front of the muzzle.

Velocity - Avg 1020 fps
Std Dev- 54.7 fps
Spread - 215 fps

Yeah, look at the spread. 215 fps. That sucks. Accuracy was okay, and shows promise, but it was by no means anywhere close to the best I've done.
I did some reading after shooting this (why do I always do this bass-ackwards?). I looked in my copy of Powder Profiles, the new edition. In it, author R.H. Vandenburg, Jr. tells of his tests with AA #9. He states that the powder is slow enough that a very firm crimp is beneficial in getting efficient burn from the powder.
Perhaps that is what my problem is. I did put a firm roll crimp on these rounds, but crimp is such a subjective thing. I have a Lee collet crimp die (NOT the Factory Crimp die), maybe that is the answer.

At this point, I can go several ways.
1- I can keep chasing this load. It is essentially a down-loaded 180gr plain base 357 Mag load.
I can try different crimps.
I can even try a gas-check, to see if the barrel cleans up.
I can try a heavier charge - Lyman cast #4 shows 12.4gr of AA#9 (IIRC) as max, but I'm wanting something around 1050 fps or so. 1100 wouldn't bother me. The spread may clear up at a higher pressure - which is what the tighter crimp does too, BTW - raises pressure. If the spread tightens up, I'm betting the accuracy will too.
I can even turn around 3 times, and click my heels prior to firing.

2- I can throw in the towel with the #9 powder. It may just be too slow for the results I want. Perhaps a move to a somewhat faster powder would help. I have AA#7, and even some old BlueDot (in a cardboard can). Even faster, I have (a bunch) of HS-6.
A faster powder would bump up pressure, helping the base of the projectile to obdurate, maybe clearing up the leading.

3- I can give up all of it, and take up bowling.

Nah... they won't allow me to wear my emerald slippers on the lanes.....

 

[Dumpstick]

Still chasing this load. Here's what I've done with this since last week.

I loaded some of these TL358-175PB up using AA#7. I'm thinking that the #9 may be too slow for what I want.

I went with PMC brass, CCI #550 (SP Magnum) primers. Western Powder #6.0, and Lee #2 (pg208) agree on the charge weights - something like 8.2 - 9.3gr. I went with 2 loads - 8.5 and 9.0gr. I'm still looking for 1050-1100fps

I fired these on the 9th, from a 4" Ruger Security Six. 18 shots each. Some of the shots produces an error on the chrony, the 8.5g load is 14 shots.

Charge weight Speed Std Dev. Spread
8.5gr 900 fps 16.6 49
9.0gr 968 fps 18.0 63

The numbers look good, it's a fairly efficient load. I've seen 90+ fps spreads on factory ammo, so I'm not too worried about the numbers I'm getting. I fired some factory Federal 125g JHP from a 6.5" Blackhawk (the same day), and got 70+ fps spread, along with ~1650fps muzzle velocity (!!!!)
Also, I don't think I'm a good enough shot, or that I'm shooting at enough distance to notice the difference. Both loads were easy shooting, but the Pachy grips on it tend to work very well for me. Brass fell out easily, no indication of pressure. Brass was clean, no soot.

Target for the 8.5g load. 25', standing, two hand hold, no support.

That's about a 1.5" dot in the center, the group is 4 3/4" x 4 1/4". The 9gr load was similar, but centered about 1.5" higher (!) on the target, even though it was traveling faster. I never shoot all that well over the chrony, I'm certain I can do better.

Note : That Ruger needs help. It was leading again - I looked down the barrel, and it looks like the rifling was chiseled in. I may have to fire-lap this thing to get it to quit leading.

Where am I at with this ? Well, I don't know.
I can use the 8.5g as a target shooting/casual load. However, I can shoot much more accurately (not to mention economically) with a wadcutter and 3 grains of something fast.
I can keep the 9.0g load as a field load. Certainly, 180 grains traveling at 950+ fps is a capable round. If I put it in the 6.5" Blackhawk, or the 6" GP-100, I will probably flirt with 1050 fps, my original goal. Although, I really don't go woods walking as much as I did 20 years ago.
I can try this with a gas check. The mold is a 4-cavity - 2 plain base/2 gas check. I can try some of these with a gas check, and put the fuel to it - make an almost-max round with the #9 powder. For that matter, I can fire it all the way up with some H110 !

When I purchased the mold, I wanted to use it in a .357 Handi-rifle that Mrs Dumpstick owns. It chambers 360DW brass easily, and I wanted to see what this 180g would do in there, gas-checked and lubed up. I think it would make a formidable deer/hog round, at 1500fps or so, easily a 100 yd rifle.

 

[Legend]

Seems like that would make a nice plinker bullet for a 357 Max rifle round.

 

[Dumpstick]

It probably would. I haven't tried 357 Max in the Handi-rifle, as I don't have any to try. Most of these carbines will not chamber the Max without reaming, and I would rather leave this one stock.
I do have 360 DW brass, and I really think the 360 DW will do whatever I need doing with the carbine.
I'll mess with this some more later.