second opinion on heavy AA7 load in 357

[someguy2800]

Hi guys,

I would like to get some opinions on a pretty hot load I am working up for a deer hunting load. I load alot of rifle but I am new to loading magnum revolvers.

I have a new Ruger SP101 4.2 inch barrel that I bought to use as a close range backup gun deer hunting. I am currently loading some Prvi Partizan 158 gr JHP bullets I got on the cheap for sighting and practice, and once I use them up I will switch over to a hornady 158 XTP's and will work the load up again from the bottom.

Slow pistol powders like 2400 and h110 are very hard to find locally but I found some AA7 so I picked up a couple pounds. It is about the same burn rate as bluedot. Acurate lists a max load of 10.5, lyman list a max of 11.5. Using WSP mganum primers.

I was working my way up today and found moderately high pressure in the 11-11.5 range, brass sticking just a bit and mildly flattened primers, but to my surprise the pressure dropped considerably at 11.6. I have gone up to 12 grains and have absolutely no pressure signs. Very easy extraction and no primer flattening. For you magnum revolver guys out there, do you think I am safe in this range or am I playing with fire? One of the reasons I got the AA7 is it is low flash and is supposedly pretty temperature insensitive. It is often below zero where I hunt. Does AA7 have any bad habits that will get me in trouble here?

 

[gamestalker]

Is there any way you could borrow a chrony? That sure would help to let you know how well it's performing in terms of velocity anyway.

I haven't tried that combination before, but it should be fine if you get the charge up high enough, while watching for sticky extraction.

Nosler indicates AA7 as the most accurate load tested at 11.2 grs..

Sierra also list AA7 as the most accurate powder tested, but at 11.7 grs., but with a max published charge of 12.0 grs..

Speer has a max charge of 11.7 grs..

Accurate indicates a max charge of 9.6 grs. with a 158 gr. XTP.

So based on the available published data, your 12.0 gr. charge is at least within published max, though I don't know that I would bump it up any higher.

IME, once you break that little time barrier, pressures begin to drop back down some, cause the bullet is getting out of the case in better time with peak pressures. It's all about timing, and determining what powder charge will deliver the most optimal peak pressure, and at the right time. This is why faster burning powders don't work well in a magnum application, they peak too quickly, therefore pressure will go excessively high before the bullet can exit the case mouth. AA7 seems to be some where around the cusp, a mid burn rate powder in this application, so you should be fine where you're at if your reading pressures correctly. But I don't think I would bump it up any higher.

Good luck & Shoot Straight!

GS

 

[murf]

h110 will act the same way. as the powder charge is increased above a certain amount, velocity will decrease. as more powder is added, the velocity goes back up. i wouldn't go any further with your powder charge as you are already at the top of the charge range.

i would suggest switching to a non-magnum primer and working up the load from the bottom of the charge range. aa7 doesn't require a mag primer.

luck,

murf

 

[someguy2800]

Thanks for the advice guys. Its good to know there is published data in this load range. I am very comfortable reading pressure signs so I am confident that I'm safe. My main concern was if AA7 had any bad habits at high or low temps like bluedot. I used the magnum primers since these will likely be used at 0-40 degrees F. Also lyman and AA both listed wspm in there data. I will also try working it back up with a standard wsp and see if there is any accuracy difference.

 

[Walkalong]

I feel your pain trying to find a more suitable powder locally, but AA #7 isn't a good choice for max .357 loads, which is what I assume you want ("hot load") for deer hunting. H110/W296, N110, AA #9, Enforcer, 4227, etc would be much better choices. Any of those available locally?

AA #7 should be great for some midrange loads.

 

[joneb]

AA #7 should be great for some midrange loads.

I agree. One of my favorite loads for a 2.75" Ruger Security six was with 158gr Rem JHP standard small primers and 10.2gr of Accurate #7. Never chrono'd it but it was very accurate and low flash.

 

[someguy2800]

I feel your pain trying to find a more suitable powder locally, but AA #7 isn't a good choice for max .357 loads, which is what I assume you want ("hot load") for deer hunting. H110/W296, N110, AA #9, Enforcer, 4227, etc would be much better choices. Any of those available locally?

AA #7 should be great for some midrange loads.

I have been on the lookout for literally all of those but no luck. If I spot any H110 at a gun show I will give a whirl just to see. The loads I am getting from this AA7 are plenty hot in this 30 oz gun so I am happy with it. The lack of giant fireballs are also a nice benefit for hunting. Big muzzle flashes can really screw up your vision when trying to see where that big buck runs into the slough in low light conditions.

 

[someguy2800]

I've been doing some more research on this. Knowing that the burn rates on this is very similar to bluedot, and load data for AA7 seems to be similar to bluedot, I had suspected that velocity of AA7 would closely mimic bluedot.

Well I happen to have found a test with this exact bullet using several powders in two guns.

http://www.reloadersnest.com/forum/topic.asp?TOPIC_ID=19289

For what its worth, in this test 11.5 grains of AA7 almost exactly matched 11.5 grains of bluedot in the 6 inch gun. In the 4 inch gun bluedot was actually exceeding H110/296, enforcer, 4227, and AA9! It was only bettered by N110, MR300, and 2400, and not by a whole lot. The slower powders did outperform bluedot and AA7 in the longer barrel, which would make sense to me. I will have to get a chrony and see for myself. Either way i don't think this AA7 is half bad considering it is much more economical, and has almost zero flash. It is also not know for the low temp pressure spike that blue dot is know for, or so the internet tells me.

 

[Steve C]

You don't need a maximum load to kill a deer. You can load to typical factory velocity of 1,300+ fps from a 6" barrel using Accurate on line datar for AA7 with a Nosler 158gr JHP at 10.5 gr. If you think you need more velocity get a 6" plus barreled handgun, carbine of rifle.

You may be able to get 100 fps faster using 2400 or H110 but with handguns and archery shot placement is more important than a few fps +/-.

 

[someguy2800]

I agree 100% and will always chose accuracy over velocity, but out of respect for the animal I personally believe in factoring in as much overkill as is comfortable for you to shoot. Its easy to talk yourself into having "just enough" gun. You have to draw the line somewhere which is why we don't deer hunt with 9mm's and 22 mags.

 

[Walkalong]

I would like to get some opinions on a pretty hot load I am working up for a deer hunting load.

I guess I took that the wrong way then.

 

[someguy2800]

I guess I should have asked, does anyone have reason to believe this load will blow up my gun?

 

[Sunray]

"...believe this load will blow up my gun?..." Nope. Lyman actually does test loads(as opposed to places like Lee who do not) and would get sued into next year if they published anything that was unsafe. Does sound on the edge of excess pressure though. Cases sticking and flat primers.
What you will see is a difference in velocity due to different barrel lengths etc.
Why do you think you need a "back up" handgun for deer if you have a rifle? Just curious.

 

[someguy2800]

Some of the people I hunt with are up in age and shot placement is not always the best. Me and my brother in law usually take the point on all the tracking for the group and I have had several occasions that a handgun would have been useful. For example a few years ago I had tracked down a buck that my brother in law had shot and in the heat of the moment I accidentally double stroked the bolt on my rifle which pushed a second round out of the magazine and bound up the gun with the deer struggling to get up and run again 25 yards away. I had to drop the magazine and reload to clear the jam, luckily my brother in law got there in time on put it down while I was fiddling. I've also had scopes get full of snow while tracking in thick brush and become useless.

 

[someguy2800]

On another occasion I once shot a spike buck to fill one of our antler less tags at about 50 yards. The deer jumped after it had been shot like it was hit but only ran 20 yards and then stopped and proceeded to wander around under my stand for 30 minutes. I knew something was wrong so I put the gun down. Testing back at camp showed the Cabela's scope had moved point of impact by 8 inches at 50 yards. I went back the next morning and luckily shot the same deer using a borrowed rifle. The deer had a 4 inch graze that split the skin open on the bottom of the chest.