NOE-360-160-WFN and Accurate #9 in .357Mag

My first shot at AA#9 in .357 Mag worked much better than Enforcer. I had to do some figuring on a good starting load since the wide flat nose, small lube grooves, and small cannelure translates to a relatively short bullet (0.625” long, and 1.585” COAL.). I calculated that the Lyman 358429 (170 grains) and Lyman 358477 (150 grains) both had a 77% case fill, so I used that to get a starting point of 13.9 grains. The max charges for four lead bullets in this weight range in Lyman’s 49th have max charges that range from 13.0 grains to 14.5 grains and max velocities from 1,221 to 1,350 fps (4” barrel on a universal receiver.). Western Powder’s #1 shows a max charge of 12.4 grains under a 158 grain SWC yielding 1,255 fps from a 6” barrel. I decided to load up 6 rounds @13.7 grains, 6 rounds @13.8 grains, and 6 rounds @13.9 grains and shoot them out of a 3” DAO revolver. My chrono gave me this:
13.7 grains -> 1,217 fps average; 26 SD
13.8 grains -> 1,252 fps average; 24 SD
13.9 grains -> 1,241 fps average; 26 SD
Primers all look good and cases all ejected easily. No leading.
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I’m thinking 1,200 fps with 94-4-2 alloy will take care of an Appalachian black bear if the next one I see in the wild isn’t as friendly as the previous and the recoil is plenty for a challenge at the range.
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I don’t plan to go hotter with this combo, but I am curious about everyone’s thoughts on what might be a safe limit here for a modern .357Mag (not a Ruger). Should I target 1,100 fps for this 3” barrel?

It seems to me that you are riding the ragged edge there.

Without knowing how much of the boolit is going into the case, it makes it difficult to tell which of the possible alternates is the best match, but looking at the Lyman Cast Bullet Handbook #4, they show max charges of AA 9 for the 150 grain 358-477 as 13.5 grains. 14.5 is the max for the 358-156, 155 grain boolit, while the max for the 358-665 158 grain and 160 grain 358-311 boolits is 13.7 grains. Speer also shows 13.7 as max for their 158 grain Jacketed rounds. Hodgdon's 2022 annual shows 12.4 max for a 158 SWC, while 13.8 is their max for a Hornady XTP jacketed.


It would appear that your loads are at or above the max loads for every one of these boolits except the gas checked 358-156. If you are not shooting a Ruger, maybe you might want to consider it.

I think you’re right. I was pursuing the data at ballisticsbytheinch.com and it looks like 1,100-1,125 fps is probably the max velocity I should be looking for in this barrel. I will look into how low the charge can go before it no longer burns clean.

Just to give you an idea for a bit of comparison, I ran 13 grains of AA#9 with a 158grain Lee RNFP bullet and chronographed it at an average of 1214 fps with a standard deviation of 32 fps through a 4” Python.
I agree with you that the AA#9 performed noticeably better than the Enforcer powder I tested.

I run 11.4gr of #9 with the 360 - 160 WFN in my 10 T/C . That's the min charge from Accurate for a 158 LSWC .

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AA#9 has a wide range of max charge and peak velocity for bullets between 150 and 160 grains, and it doesn’t seem like case capacity is the only significant cause in that difference. Looks like AA#9 and custom .357 bullets should not be pushed to the max in a typical revolver.

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Originally Posted by Targa

Just to give you an idea for a bit of comparison, I ran 13 grains of AA#9 with a 158grain Lee RNFP bullet and chronographed it at an average of 1214 fps with a standard deviation of 32 fps through a 4” Python.
I agree with you that the AA#9 performed noticeably better than the Enforcer powder I tested.

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Thanks for that information. What is the length of that boolit and what is your OAL?

Good report. I think you have probably found the top. Backing off a little and checking your SDs is probably a good idea. Carry on you are doing a fine job..........

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Originally Posted by ddixie884

Good report. I think you have probably found the top. Backing off a little and checking your SDs is probably a good idea. Carry on you are doing a fine job..........

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Thank you. Comparing the load data for the different bullets in this weight class has been surprising to me. The 358156 (155g) takes a greater charge than both the 358477 (150g) and 358311 (160), while traveling at the lowest velocity… even slower than the 358429 (170g). I suspect that both the number of driving bands and the size of the cannelure matter significantly here. It seems like the 358156 has more drag inside the barrel, and if that is caused by the multiple lube grooves then my NOE-360-160-WFN will have similar drag and similarly low “er velocity.
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Now I’m looking at Accurate #7, because it has a range of 0.5 grains in the max published load data for these three bullets plus two j-word bullets also listed in Lyman’s #49. If my high barrel drag hypothesis is right then I should see around 1,000fps and if it is wrong I should see around 1,100 fps. N110 has a range of 1.0g for these three boolits, the relationship between boolit weight and charge level is strong enough to hold a linear correlation, and the charge per unit case capacity also jives. HS-6 has a range of 0.3g across these three boolits, and Bullseye has a range of 0.1g.
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The most important thing I’ve learned here is that I should not pursue max performance from a custom boolit without published data. The next thing I learned is to compare the range in max charges for bullets above and below the weight of a custom bullet, and choose the powder with the smallest range.

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Originally Posted by justindad

Thanks for that information. What is the length of that boolit and what is your OAL?

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Sorry, I meant to answer you yesterday and I forgot. Bullet=.632” OAL=1.55”

As mentioned, very good work-up. ONE thing disquiets me a little, however. The velocity for 13.9/AA#9/160 is slightly lower than that for 13.8/AA#9/160. This COULD be just instrumental error, but it could also be an indication that you have reached the maximum safe load for that combination, and you may be near an over-pressure situation. Since 0.1 gr. less gives you higher velocities anyway, perhaps that is your best stopping point.
It occurs to me that you may already know this, but I thought it worth mentioning, just in case.

Thanks Targa & Kosh. I was also thinking about the higher speed for the 13.8g charge, but wasn’t sure since the difference in the average is about half the SD.
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I just poured 8g of HS-6 into a few cases. I’ll work that up to max, and if the speed there is relatively low then I’ll conclude I was over pressure. I’ll be surprised if I wasn’t over pressure. I’ll report back, but it’ll be three range trips and about a month before I get to the top of HS-6.

You COULD be perfectly fine, pressure-wise, but I would be remiss in my duties as a fellow reloader had I not mentioned the possibilities of bad portents. How did your primers look, on those AA#9 reloads?
And I forgot to mention that I think you could not have picked a better projectile for use in a .357 Magnum lever-gun.

I definitely appreciate your concern. The primers looked normal. There wasn’t any extrusion around the firing pin and the corners were still round. I called the manufacturer to ask what they they tested with - SAAMI pressure and up to 158 grains. No CIP pressure and no 180 grain bullets.

Two new data points with the NOE-360-160-WFN:
1) 8.0 grains of HS-6 gave me 972 fps and ES of 29.
a) Lyman 358477 starting load is 9.0 grains for 1,103 fps (4” barrel)
b) Lyman 358156 starting load is 8.8 grains for 1,069 fps
c) Lyman 358665 starting load is 9.2 grains for 1,150 fps
2) 13.8 grains Enforcer gave 1,164 fps and ES of 47.
a) Lyman 358156 max load is 13.8 grains for 1,293 fps
b) Lyman 358665 max load is 14.0 grains for 1,312 fps
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Ballisticbytheinch.com gives a velocity loss range of 110 fps to 220 fps going from a 4” barrel to a 3” barrel. I imagine the 110 fps sample used a faster powder than the 220 fps sample. I’m going to step up to the starting charges of HS-6 for each of these, as soon as I get a new chrono (I shot mine).

Velocities measured at roughly 7 yards, average of 12 rounds.
.357 Mag; 8.8 grains HS-6; NOE 360-160-WFN
1,065 fps
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.357 Mag; 9.0 grains HS-6; NOE 360-160-WFN
1,087 fps
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.357 Mag; 9.2 grains HS-6; NOE 360-160-WFN
1,124 fps
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.357 Mag; 13.7 grains Enforcer; NOE 360-160-WFN
1,184 fps
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The greatest speed gap from published HS-6 data is 26 fps, which seems small given the 1” shorter barrel. I cannot tell which bullet this matches best at this point.
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It seems that, with this 3” barrel and boolit with a shallow cannelure, HS-6 may outperform Enforcer at max loads.

.357 Mag; 9.7 grains HS-6; NOE 360-160-WFN
1,144 fps (18 shots)
34 SD
Book data for 155 gr Lyman 358156 gives 1,271 fps.
Book data for 160 gr Lyman 358311 gives 1,225 fps.
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.357 Mag; 10.0 grains HS-6; NOE 360-160-WFN
1,174 fps (18 shots)
29 SD
Book data for 150 gr Lyman 358477 gives 1,301 fps.
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.357 Mag; 10.2 grains HS-6; NOE 360-160-WFN
1,182 fps (18 shots)
12 SD (group size was half of the lighter charges)
Book data for 158 gr Lyman 358665 gives 1,253 fps.
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.357 Mag; 13.7 grains Enforcer; NOE 360-160-WFN
1,152 fps (6 shots, same batch as July 5 data)
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I’m still not sure which bullet this mimics the most, but the significant increase in accuracy at 10.2 grains is interesting. Brass was not sticking in the cylinder and primers look good.
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Attachment 315856

The max speed out of 18 shots with 10.2 grains of HS-6 was 1,201 fps.
The max speed for 10.0 grains was 1,238 fps.
So while the average speed was higher for 10.2 grains, the max speed was lower - which was caused by the change in how consistent the powder performed. Therefore, I suspect that the max pressure for 10.2 grains was not higher than the max for 10.0 grains, even though the average pressure for 10.2 grains was higher. Therefore, I am not concerned that 10.2 grains is giving meaningfully higher pressures than 10.0 grains. (That does not mean that either charge weight is below the SAAMI limit.)
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The Lyman Cast Bullet Handbook #4 shows that the most consistent powder for the Lyman 358665 is HS-6 at the max charge of 10.2 grains. The other three bullets show IMR-4227 and 2400 as the most consistent powders. I have some IMR-4227. If this boolit does relatively poorly (SD>20) with IMR-4227, then I will believe that the load data for the Lyman 358665 is the most relevant to the NOE-360-160-WFN. Of course, my barrel is 1” shorter than what Lyman tested with, so the very slow IMR powder may not do as well for that reason alone. I might need to do more testing with a longer barrel.

A lesson in here could be that, when figuring load data for a custom boolit, start with a known accuracy powder of a similar boolit to see if the accuracy characteristic remains. If the accuracy remains, then the powder burn characteristics are likely similar for that powder, and perhaps for all powders. Doesn’t confirm, but does help with confidence.
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Practically speaking, this would imply that it would be best to start with H110 data from the Lyman 358665.

I have had a similar problem working with some of the newer style molds. For 357mag, I'm using the MP 359-640 which with my alloy drops the large cavity hp at 160grs.

Like you I searched for similar data and made use of the Lyman manual, a similar weight bullet, and AA-9. Personally I prefer this powder as it gives a bit more leeway on the load range than 110, and burns a bit cleaner with less muzzle flash
than 2400.

I am loading for two GP100'S and a Contender so have a bit more wiggle room with pressure, but even running 13gr all the cases drop out on their own and primers still carry round corners.

Good luck with your work ups.