Loading .357 with Accurate powders

[TonyAngel]

Hey guys,

I'm trying to figure things out and settle on something to shoot out of my Blackhawk. I just ordered some 2400, but I'd really like to be able to work something out using Accurate powders. I can get them locally and it would just make my life easier.

Does anyone here load .357 using accurate powders? I'd like to use Accurate No. 7. It's on the slow side, but I think that my 4 and 5/8" barrel can make use of it. I don't think that No. 9 would be the best for my short barreled Blackhawk.

This is my quandry. I use 158gr LSWC projectiles from MBC exclusively. The Accurate website lists loads for No. 7 ranging in charge weight from 9.1 to 10.1 grains and calls for a magnum primer. These loads show pressures approaching the upper limit for .357, but the velocities are kind of sedate.

I just bought a Complete .357 Magnum handbook. This book lists loads using No. 7 ranging in charge weight from 9.9 to 11 grains and calls for a standard primer. The resulting velocities are what I'm looking for and the pressures equal those of the loads listed on Accurate's website.

Can someone tell me what's up with the discrepencies? Can someone fill me in on their experiences with No. 7? The only difference between the recipes on Accurate's website and those in the Complete handbook are that the Accurate recipes call for magnum primers and the handbook calls for standard primers. So, what, can I use the data in the handbook as long as I use standard primers? Is the use of the magnum primers in the recipes on Accurate's website the reason for the reduced charge weights?

I'm thoroughly confused. Can anyone shed some light?

 

[broham]

I haven't used #7 in my GP100, or lead, But have used lots of #5 and #9. The #9 is for hotter loads but H110 I think is better. I use the #5 for my target loads with a 158 sjhp. I believe I was loading about 9.5gr's. A lot of manuels call for a mag primer but I only use them with H110.

 

[joneb]

Can someone tell me what's up with the discrepencies?

Could be the bullet used for testing or the firearm ? or a half a dozen other things
I have loaded AA#5,7 and 9 with jacketed and lead bullets using mostly small pistol primers. The barrel lengths of my .357 mag revolvers are 2.75 and 4" I no longer use AA#7.
For swaged lead and cast bullets 12-14 bhn I like Bullseye and AA#5 these loads would be in the 38spl, 38spl +p and +p+ category all with standard sm pistol primers.
For jacketed bullets 158-180gr and hard cast lead 18-22 bhn or gas checked with weights of 158-180ish I like AA#9 with standard sm pistol and some magnum primers.
With most these loads loads I find better accuracy with the standard primers, but for outdoor carry loads I will use magnum primers.

 

[TonyAngel]

I've been surfing through load data. It appears that Accurate has gotten really conservative with their data. I wonder if the powder's changed or they just decided to get conservative. Another member here mentioned in another thread that Speer's published data for an Accurate powder was hotter than that published by Accurate.

 

[ArchAngelCD]

Tony,
AA#9 is the real Magnum powder in the Accurate line but for lead bullets you might be better off using AA#7 although your BH with a barrel of almost 5" can use the slower AA#9 just fine. It's the heat and pressure that would worry me if it's a worry at all. (BHN 18+) If you're bullets are very hard cast I would use AA#9 to achieve the velocity you're looking for. I've loaded 158gr SWC Laser-Cast bullets (BHN ~21) with a full charge of 2400 without any leading to speak of.

 

[GP100man]

Jibjab , ya almost hit it !! Theres so many lead bullets from different mold makers that the load data has to cover !!

Some seat deep & some don`t & pressure in individual handguns vary per say.So they & there lawyers come up with a solution.

Remember also that as time goes on there`s new & more accurate ways that SAAMI pressures are measured!!

Just stay alert & follow good handloadin proceedures & enjoy !!!

 

[zxcvbob]

AA#7 works great with 158 cast bullets. It is very similar to Blue Dot. I load more than 10 grains; usually with a Wolf small rifle primer. Don't have my load data handy for the exact details, but you need to work that up yourself anyway.

This book lists loads using No. 7 ranging in charge weight from 9.9 to 11 grains and calls for a standard primer.

That sounds right to me.

 

[jfh]

Tony, I've followed that AA "conservatism" in their data. It's important to remember that AA is a "brand-name only;" they subcontract with different actual manufacturers for their powders. Some years ago they actually published revised specs simply because their new supply of--of what, #2?--was hotter.

The next element in that increasing conservatism is, in fact, better measuring techniques--or at least more repeatable ones. Combine that with the corporate-speak for liability issues, and we probably do have more accurate (if not safer) manufacturer's recipes today.

When I got going on my short-barrel reloading project, I really settled in on AA#5--which lead me to True Blue--which lead me to correspondance with Ramshot, and some ongoing e-mail exchanges with their ballistician. Based on what he told me, I'm content with the current recipes and pressure representations in the latest Ramshot manual (for example). However, I am not sure how that plays into Accurate's data. Ramshot may be keeping hands off there--

Jim H.

 

[Marlin 45 carbine]

from what I've read data manuals say to use aa9 with 158gr jacketed (and heavier) crimped well and magnum primers. I followed this in loads for a 6" bbl S&W md 28 and a Ruger GP w/4" bbl with good results as far as groups but a tremendous flash - max loads.

 

[Steve C]

I have used AA #7 with some .357 mag loads but mostly in 9mm and a few .41 mag loads with lead bullets. Don't have any chrono'd results using #7 in the .357 mag but have using #9.

The book loads for these powders have some discrepencies and I'd suggest that you use the more conservative loadings and work up if wanting highest velocity. Don't try to shortcut the development process and cherry pick a a load that you THINK will get you a velocity you want. You really need a chrono to work up loads if you are trying to get a specific velocity.

Years ago I was in a similar quandary on load data and wanted to get a full pressure cast load with some commercial cast bullets that produced leading at lower velocities and pressure. I had AA#9 and the load data in the "One Book" had Lyman listing 12.0grs to 15.0grs while the AA data listed 12.2 to 13.5grs. Lyman listed a CCI 550 mag primer and the AA data showed a CCI 500 standard. One of the "free" Accurate Arms pamphlets listed 12.2grs as maximum but the "on line data" mirrored the "One Book". Current data is more conservative and like the "free" pamphlet of that time.

I decided to load 12.2grs of AA#9 using CCI550 primers in mixed cases since it was the start load for most data and didn't exceed the most conservative max. Ran these over the chronograph from my S&W M66 with 4" barrel and their velocity was 1,268 fps, pretty much what Accurate conservative pamplet said they'd be from a 6" barrel and the pressure was high enough to eliminate the leading I was getting from the hard cast bullets with lower pressure loads. These loads shoot well and I've not had any reason to change this load when using AA#9 with 158gr LSWC cast bullets.

 

[Slamfire]

I don’t see why AA#9 won’t shoot well in a 4 5/8” Blackhawk. I have one and it shot my AA#9 loads well.

I did some load development with AA#9 in a M27-2. It shot well and I decided to use the 12.0 grain load.

These ball powders might not be the best solution in cold weather. January I had misfires and squibs with the 12.0 grain load in two different 357’s in 30-40 F weather.

Don’t know if it was the revolvers or the powder. Still the loads below shot like a champ in 104 F weather.

[SIZE="3"]Smith & Wesson M27-2 			
					
158 LRN Valiant 12.0 grs AA#9 CCI500 Mixed cases 		
5-Aug-06	T = 104 °F				
Ave Vel =	1278		 		
Std Dev =	34.98		 		 
ES  =	117.4			 
High  =	1344			 
Low  =	1226				
 N =	27				 
Accurate					
					
158 LRN Valiant 12.5 grs AA#9 CCI500 3-D  cases 		
5-Aug-06	T = 104 °F				
Ave Vel =	1348		 		
Std Dev =	34.16		 	 
ES  =	134.7		 	 
High  =	1386				 
Low  =	1251				
 N =	25
				 
no leading
					
158 LRN Valiant 13.0 grs AA#9 CCI500 3-D cases 	 	
5-Aug-06	T = 104 °F				
Ave Vel =	1360		 		
Std Dev =	33.19		 	 
ES  =	109.8			 
High  =	1393				 
Low  =	1284				
 N =	26
				 
Very Accurate					
no leading[/SIZE]

 

[zeke]

Use alot of AA-7 for 125 jhp mid level .357 magnum loads (Sierra' accuracy load). It prefers Fed 200 primers over Fed 100 primers for accuracy, with the load being used. Also use it for 9mm with Fed 200 primers. Alot of manuals indicate some powders don't "need" magnum primers. That doesn't mean the primers won't work better with magnum primers.