Jump to content
Brian Enos's Forums... Maku mozo!

AA#7 - How dirty is it?


racer-x

Recommended Posts

I've tried AA#7 a few times over the years in various open guns but have steered away from it each time due to it being dirty and worried that it would hurt the reliability of my gun. Earlier this year, I worked up some major PF 9 loads for my CK gun with MG 115 & 124's. Gun tracked great with these loads, but I had 1 malfunction where some of the unburnt particles got into my trigger bow area and limiting trigger travel so that I could not break shot. Not for me...  

 

I found the particle in the trigger bow area and saved it. Looked like a tiny blackened piece of corn cob. I've since found similar particles in my slide and other places they don't belong while shooting HS-6. One day reloading, I figured out where these particles are REALLY coming from - my JHP bullets! Seems that the bullets are tumbled as final cleanup prior to being boxed & shipped.

 

My point here is, I wrongly pinned that failure to fire on the powder. AA#7 has a lot of great qualities for 9 major.

- lots of gas works comp very well

- slow (below 3N38 on all the burn rate charts I've seen, added safety factor at major PF) 

- very dense (13.8 grains fit in a 9mm case full to top)

- easy to load fast (my 10.7 grain load doesn't fill case so much that I need to slow down)

- inexpensive compared to VV, about the same cost as WAC & HS-6. 

 

problem areas

- dirty - how dirty is it ? see pics below :) 

- very dense and fine grained - leaks a little around regular Dillon powder bar (plastic Arrendondo bar is much better)

 

HOW DIRTY is AA#7 compared to HS-6? 

I worked up some 174 PF 115 loads for my guns and wanted to test how dirty AA#7 is compared to the HS-6 I've been shooting all summer. Granted, HS-6 is considered by many as dirty, but I haven't had any malfunctions attributed to it either.

 

For this test, I started with 2 clean guns, 200 AA#7 (174PF-115) rounds & 200 HS-6 (174PF-115) rounds. Shot only the AA#7 in one gun and only HS-6 in the other.   

Disassembled & cleaned both guns after the practice session; taking pics along the way. 

 

First off, a recent pic of some offending particles sneaking their way into my gun via the JHP. 

Img_4584.thumb.jpg.781f599be2a571d0fe58462fa31e4695.jpg

 

Link to comment
Share on other sites

Dirty gun pics :)

 

Img_4601.thumb.jpg.a6b44c4711a928ed1379b009be90c419.jpgImg_4602.thumb.jpg.39dcccb471bd8f4d6c8cba93e42d6cfe.jpg

Img_4603.thumb.jpg.8ffd22381246fa318f9e0ee556f6272b.jpgImg_4607.thumb.jpg.11062c464fad82281e16ca1f59e536be.jpgImg_4609.thumb.jpg.00e22f7eb1c94b150e27b19203b9f4ca.jpgImg_4610.thumb.jpg.c28cfe6893b0ccb203d4df39e72a5021.jpg

 

And lastly, the corresponding paper towel I used to wipe down the slide, barrel & frame,  and the 1st bore patch used to clean each barrel.

Img_4613.thumb.jpg.63f68665613ef2e20bd9ead5b29f7400.jpg

 

 

This side by side comparison showed me that my perception of AA#7 as being really dirty, too dirty, etc.. were not that Accurate.

Not a significant difference that I could see in this test. A few more unburned grains of powder in the barrel of the AA#7 gun. HS-6 gun had a fine smoked or sooty residue on the gun as well. 

 

Link to comment
Share on other sites

12 hours ago, racer-x said:

HOW DIRTY is AA#7 compared to HS-6?

My load is 10.9 gr AA#7 with PD 115 JHP in 38 sc. giving me a 170PF. I found HS-6 way more dirty than AA#7. I do not have any unburned powder. I also found that my STI Trubor stays more cleaner using gun oil (Lucas) than any type of gun grease. My gun runs better wet so I apply to slide after about 200 rounds and take a qtip to clean feed ramp. Been using this routine for last 20,000 rounds with good results. AA#7 for me tracks very flat but is very loud and blasty.

Link to comment
Share on other sites

I shoot a CK open gun 38sc. My gun is never that dirty after 200 rounds and all I shoot is HS6. I just cleaned mine after a little over 400 rounds and mine was not that dirty. Let me see if I can find my bore patch. 

Link to comment
Share on other sites

52 minutes ago, andersonj55126 said:

How do you think HS-6 and AA7 compare for dot movement?

Very similar performing. In my test, I shot a few familiar drills and several variations on a simple 12 round stage. 

1-2 mags per gun and then switch guns & loads, repeating the same drills. Both guns are setup near identical (1.75 trigger pull, 17# mainspring, 8#variable rate recoil spring). Watched the dot, called my shots & focused on getting points at speed. 

- Leatham drill - my favorite drill to test & learn a guns recoil traits ( https://www.youtube.com/watch?v=YLRxohRdIys&app=desktop )

- 3 paper targets far-near-medium (25yds-5yds-10yds)

 

Best & average times between guns/loads were within my margin of error. Both loads tracked great. The AA#7 'seemed' a little flatter, but I did not shoot better points or faster times with it, even in the Leatham drill litmus test. My performance maintaining a consistent grip, waiting for acceptable sight picture & exercising trigger control was the deciding factor in the times & points. 

 

Also, examining the empty cases of each load didn't show a noticeable difference in primer flattening. 

Link to comment
Share on other sites

54 minutes ago, Steelix said:

I shoot a CK open gun 38sc. My gun is never that dirty after 200 rounds and all I shoot is HS6. I just cleaned mine after a little over 400 rounds and mine was not that dirty. Let me see if I can find my bore patch. 

 

'Not that dirty' as compared to the above pics?

 

They didn't seem too bad, but the camera and bright lights accentuate every spec.

Also, you can see in the pics that the guns are still very well oiled after 200 rounds. Maybe that is why it looks dirtier?

 

Link to comment
Share on other sites

1 hour ago, racer-x said:

 

'Not that dirty' as compared to the above pics?

 

They didn't seem too bad, but the camera and bright lights accentuate every spec.

Also, you can see in the pics that the guns are still very well oiled after 200 rounds. Maybe that is why it looks dirtier?

 

I do think you run your guns a lot wetter then I do. The rails I keep oil on but everything thing else is a flim of oil on. I never have all that powder and oil on the slide on the back side of the chamber. 

Link to comment
Share on other sites

AA#7 isn't terribly dirty in my gun but it does leave a few unburned powder granules in the barrel even at major PF.  Has never slowed my gun down, but then again its a CZ and not finicky about being squeaky clean.

Link to comment
Share on other sites

I noticed that as well.

You can see the Montana Gold JHP imprint on the flat area (AA7 barrel) where the ramp is cut on the other (HS6 barrel).

 

I haven't had any FTF's with either, but it seems like that ramp ought to be cut lower.

Link to comment
Share on other sites

I run 10.2 gr of aa7 and have shot matches with 400+rounds and have not suffered any malfunctions due to powder selection, i like it and is my go to powder

Edited by Acsr
Auto correct
Link to comment
Share on other sites

Let's talk about powder spillage...

AA#7 is a super fine grain powder that leaks quite a bit around my powder bar causing:

-inconsistent charge weights

-mess/waste with powder spillage

-jams up movement of powder bar

-damages/galls powder bar

 

I tried my Arendondo powder bar that is a tighter fit and this helped some. Solved this problem completely when I was loading another fine grain powder (True Blue), but was not quite enough for AA#7 on my equipment (Dillon 550 & 1050).

 

Next I tried adding a piece of tape to the top of the powder bar spacer to tighten up the tolerances a little. First try with green painters masking tape (.005" thickness) was perfect. Loaded several hundred rounds since with MUCH more consistent charges and no powder spilled on top of my tool heads. 

 

IMG_4625.thumb.JPG.48020067500318b8ce44aaecad7946b2.JPG

IMG_4626.thumb.JPG.ff1461f6a2f55f2875da61f1db437440.JPG

IMG_4627_B.thumb.JPG.eeb9ea6e7eaee36137e787d221a019cf.JPG

Link to comment
Share on other sites

  • 2 weeks later...

Liking this powder the best for 9 major now and got my first 8 pound container of it last week. 

Works the comp awesome with 115's and gets extra points for being a slower burn rate than any other powder I've considered for 9 major.  

My powder bar spacer mod (above) made loading much less messy & faster than loading 3n38. 

 

I  chrono'd my load with the new batch of powder yesterday and it was consistent with my first 1 pound batch I got for testing way back. 

This is always a good precaution since I've seen some extreme variations between batches of powder.

New batch had the same avg fps/PF with a lower extreme spread over 10 shots.

 

Montana Gold 115JHP at 1.165 OAL

AA#7 10.60 grains

 

Old batch powder (1#):

Avg. FPS=1501 (172.6PF)

ES= 27

temp=80F

 

New batch powder(8#):

Avg. FPS=1501 (172.6PF)

ES= 24

temp=59F

 

Link to comment
Share on other sites

I have been running HS6 in my Tanfo for the couple months that I've had it.  I have several pounds of AA#7 on hand but had given up on it with my Lee powder measures.  Used to load it to major in my .357sig.

 

I'm going to give it another look now that I'm loading with Hornady powder measures.  Anyone have data for a PD 124gr bullet in 9mm?

Link to comment
Share on other sites

I am running 9.5gr of aa7 with PD 124. Oal at about 1.160 was showing slight pressure signs. My chrono was showing about 1360fps. Got a level 2 match tomorrow. I’ll post later what the official chrono is. Also shooting it out of a Shorty with no popples and a cheely comp. I increased the oal to about a 1.172 for the match also  

Link to comment
Share on other sites

Interesting thread. Good idea on the powder bar.
 

I'll admit I have stopped using AA7 because of the blowback when shooting suppressed in 147gr 9mm, and because of how badly it jammed up the powder bar in my Dillon.

 

I was always satisfied with the results I got with it in 10mm though.

Edited by thormx538
Link to comment
Share on other sites

  • 2 weeks later...
  • 2 years later...
On 11/3/2017 at 11:14 AM, racer-x said:

Let's talk about powder spillage...

AA#7 is a super fine grain powder that leaks quite a bit around my powder bar causing:

-inconsistent charge weights

-mess/waste with powder spillage

-jams up movement of powder bar

-damages/galls powder bar

 

I tried my Arendondo powder bar that is a tighter fit and this helped some. Solved this problem completely when I was loading another fine grain powder (True Blue), but was not quite enough for AA#7 on my equipment (Dillon 550 & 1050).

 

Next I tried adding a piece of tape to the top of the powder bar spacer to tighten up the tolerances a little. First try with green painters masking tape (.005" thickness) was perfect. Loaded several hundred rounds since with MUCH more consistent charges and no powder spilled on top of my tool heads. 

 

IMG_4625.thumb.JPG.48020067500318b8ce44aaecad7946b2.JPG

IMG_4626.thumb.JPG.ff1461f6a2f55f2875da61f1db437440.JPG

IMG_4627_B.thumb.JPG.eeb9ea6e7eaee36137e787d221a019cf.JPG

I tried to put the same tape on the spacer and it just wouldnt fit

Link to comment
Share on other sites

  • 1 month later...
Let's talk about powder spillage...
AA#7 is a super fine grain powder that leaks quite a bit around my powder bar causing:
-inconsistent charge weights
-mess/waste with powder spillage
-jams up movement of powder bar
-damages/galls powder bar
 
I tried my Arendondo powder bar that is a tighter fit and this helped some. Solved this problem completely when I was loading another fine grain powder (True Blue), but was not quite enough for AA#7 on my equipment (Dillon 550 & 1050).
 
Next I tried adding a piece of tape to the top of the powder bar spacer to tighten up the tolerances a little. First try with green painters masking tape (.005" thickness) was perfect. Loaded several hundred rounds since with MUCH more consistent charges and no powder spilled on top of my tool heads. 
 
IMG_4625.thumb.JPG.48020067500318b8ce44aaecad7946b2.JPG
IMG_4626.thumb.JPG.ff1461f6a2f55f2875da61f1db437440.JPG
IMG_4627_B.thumb.JPG.eeb9ea6e7eaee36137e787d221a019cf.JPG

Call Dillion to send you a thicker spacer bar, it should solve the powder leakage problem on the powder bar.
Link to comment
Share on other sites

Or, try some different tapes until you find one that works.

 

Some clear packing tape or scotch tape may be a little thinner and work perfect for you.

How thick is the tape you tried? Mine was .005"

Link to comment
Share on other sites

Create an account or sign in to comment

You need to be a member in order to leave a comment

Create an account

Sign up for a new account in our community. It's easy!

Register a new account

Sign in

Already have an account? Sign in here.

Sign In Now
×
×
  • Create New...