I've been developing a jacketed round for use in my Model 66 and would like to use the AA#9 I've already got along with a 158 grain JHP and CCI 550 primers.

In reviewing my various reloading manuals I noticed that the newer the reloading manual I look at the lower the charge weight range for AA#9 is. The drop at maximum charge is quite a bit lower in the current manual compared to an older version.

I don't know if the powder formulation has changed, if the older charges were trully to hot and they have since reduced them or what exactly is going on.

My most recent manual shows a max load of 11.5 grains. One of my other manuals of the same manufacturer lists a max load of 14.3 grains.

Anyone else using AA#9 with the 158 JHP and CCI 550 primer? If so, what is the max of the range your using?

Accurate Arms says 15.0 with a 158XTP, and XTPs usually run higher pressures than other jacketed bullets. I'd believe the manufacturer.
http://www.accuratepowder.com/data/P...20to%20102.pdf

Recon,


I noticed that you used the term "158 gr JHP" generically without mention of the specific brand,etc.It makes a difference.Some bullets seat deeper and some have a longer bearing surface,etc.The same charge will NOT give the same pressure and velocity with all 158 gr jhp bullets.

canoe on the yukon:

Sorry, I should have mentioned the reloading manuals are Hornady and the bullet is the 158 XTP.

Regards...

I've loaded 158gr JHP's(any of them but Remington is my favorite) for years over 12.5 grs of #9. My chrono says +/-1250 fps in 6" barrel depending on the gun. Run 158 gr cast at the same level. POI at 25 yards is about 1/2" lower than the jhp's. I just started shooting that load from a new 8lb'er of NEW #9 with like results. Actually, accuracy with Penn 158 CTC's seems slightly better than the jacketed stuff but neither one is lacking in that department!

Recon,

I've looked at the Hornady 4th and 5th editions and see the difference that concerns you.I have some additional data which may help.


According to the Accurate 2000 guide,they're using the Hornady 158 gr JHP and show 13.0 grs for 1261 fps from a 6" revolver.......In their 1992 edition,they show 15.8 grs. giving 1331 fps from a six inch revolver for a 158/160 bullet but do not specify the exact bullet.(although it's clear that it's for jacketed because lead is listed seperately)By the way,they're using the CCI-500 primer for each of these.


According to a couple of Lyman manuals......

Pistol and revolver-second edition....The Hornady 158 gr jhp w/CCI-550 primer,they show a starting load of 13.0 gr for 811 fps and 19,600 cup.........Max load of 16.0 gr for 1243 fps and 39,400 cup.

48th edition......Same bullet and primer....13.4 starting load for 1158 fps and 32,900 cup.......Max load of 14.9 gr for 1357 fps and 42,900 cup.

All of the lyman data is using a 4"vented test barrel.

This may help and it might also make you more uncertain than ever.If possible,it might be a good idea for you to chrono your loads.That,in itself ,can shed a lot of light on things.

canoe:

Agree on the chrono. I've got some different charge weights from 10.0 to 11.5 grains loaded up and will see how they do speed wise. I tried firing these recipes from the lightest through the 11.5 and didn't see any signs of pressure. Depending on how they chrono I might carefully work up to the higher max load data above 11.5.

I also tried the starting load of 10.0 grains with the WSPM and the primers on these showed signs of pressure right off the bat. It doesn't look like this primer variation will allow me to get anywhere near the max load shown by AA.

If I can get velocity around 1250 fps I think that will suffice for my purposes. If that load doesn't get results in the field I'll get my 629 out and go from there.

Recon,

I don't personally use AA#9 powder but all the data I've seen tells me it's excellent for hot magnum revolver loads.Some modern data is conservative to a fault.

I may seem to ramble here a bit but I'm reaching for a point.The powders which really stand out for hot magnum revolver loads are (W-296,H110,VV-N110,AA#9,2400).Notice how AA#9 is one of them?If you're not getting 1200 fps (and above)then you'll know that the data is too light.Since you have a chronograph and an assortment of data,the chrony can tell you a lot

Some of the loads which I've been using for years are too hot according to "some"modern data.It doesn't bother me in the least.

Look at the data you have collectively(not just focusing on the lightest).I'll repeat what I said above."If you're not getting 1200+fps easily with AA#9,the data is too light.

The 1st Edition Accurate Arms reloading manual tested loads in a SW686 with a 6" barrel.
They used Hornady-Frontier cases and CCI 500 standard primers.
With a 158gr Hornady XTP seated to 1.580" oal using AA#9 powder
11.7--1110fps
maximum--13.0--1261fps---34000psi
They didn't use CCI 550 magnum primers with these loads so I don't know what the effect using mag instead of standard primers would be. I load 13.0 grains with CCI 500 primers in a 6" Colt pistol and also use the same load in a Marlin rifle. It is a very accurate load in both and shows no pressure signs with various cases. I think later data has a higher maximum load but I see no need to go higher. You don't have to use a magnum primer with AA#9 powder.

If there is a set of powders that works better than the Accurate Arms line for being able to adjust your velocity, I can't think of it.

There are powders that work as well at getting the velocity posted by these powders, but reducing them usually ends up with unburnt powder left behind. In the Accurate Arms line all you have to do is go with a lower number and viola, you have just the load you want.

I haven't done extensive tests with AA#9 in the 357Mag. I have loaded a MILSURP powder, WC820 - it uses AA#9 data to load with, with good success. In fact, son #1 took a deer with my 158gr LSWC load with his Marlin 1894CB rifle. The deer was DRT.

Clean, perfect metering, low muzzle flash, standard primers, decent accuracy are all good reasons to use AA#9 for your magnum loads, whatever the caliber.

#9 pretty much sets the standard in 10mm, too. As you can see from Wayne M's post, with a 6" barrel you'll usually meet (or exceed) Accurate's published data. One of the primary reasons I adopted the AA powder family is that their data are real world, unlike some manufacturers I won't name. Hodgdon. Hodgdon. Hodgdon. OK, so I did after all.

I've ran 2 loads using AA#9 that work well with Remington bulk jacketed and hardcast lead 158gr bullets over the chrono.

12.3grs using CCI 550 mag primers and 158gr commercial hard cast ran 1,268 fps out of my S&W M66 4". This load had no leading.

13.0grs using Winchester Small pistol standard primers with 158 gr Remington JSP's ran 1,268 fps from a 6" Colt Trooper MK3 and 1,102 fps from a 3.5" S&W M27.