New Chronograph and Some Interesting Data

[Driftwood]

Just received my new Caldwell chronograph last week.  I took the opportunity to load up some potential deer hunting loads using 180 gr. Hornady XTP bullets.  I am shooting a Glock 20 with a 6 inch KKM barrel.  It was quite the eye opener to see how fast the rounds that were loaded with AA#9 are actually flying!  I also loaded some Blue Dot loads that were pretty close to what I expected.  I used the Hornady load data to develop these loads.

180 gr XTP
Winchester LP
1.26 OAL
14.4 gr. AA#9
Average velocity - 1399 fps (Hornady data states 1200)

180 gr XTP
Winchester LP
1.26 OAL
14.6 gr. AA#9
Average velocity - 1426 fps

180 gr XTP
Winchester LP
1.26 OAL
14.9 gr. AA#9 (Book Max)
Average velocity - 1409 fps (Hornady data states 1250)

180 gr XTP
Winchester LP
1.26 OAL
10.7 gr. Blue Dot
Average Velocity - 1276 fps (Hornady data states 1250)

I also shot a 180 gr Speer Gold Dot that I had loaded with AA#9
180 Speer GDHP
1.255 OAL
13.0 gr. AA#9
Average Velocity - 1270 fps (Way faster than any book data I found)

As I am sure most of you have noticed, the Hornady load data has quite different numbers than what Accurate provides.  Hornady has max load for AA#9 at 14.9 gr at 1.26 OAL.  Accurate has 13.5 gr at 1.25 OAL, however both estimate about 1250 fps.  My Blue Dot loads came out very close to book velocities.  As you can see, about 25 fps faster than book, but that should be expected with my 6 inch barrel.  What completely surprised me was achieving over 1400 fps while staying inside Hornady data numbers.  Even the Gold Dot/AA#9 loads were much faster than expected.  I was also a bit surprised to see the max load of 14.9 was actually slower than the 14.6 load.

None of the loads showed signs of over pressure other than the primers were a little flattened with the AA#9 XTP loads.  Is is possible the 6 inch barrel is providing that much of a jump in velocity when the AA#9 powder is being used?  Either that or my can of AA#9 is super charged!

[The_Shadow]

Yes, the 6" barrel is responsible for the increased velocity.  Usually you can see 65 fps + per inch and the Hornady books show the Delta Elite with a 5".  The AA#9 is a slow enough powder that the extra length helps out even more so!

Thanks for the report...

[nickE10mm]

Those numbers sound entirely possible using a 6" KKM ... in fact, I recently tested AA9 with the 200gr XTP and got ~1370 or so with 13.2gr from a 6" tube.  It surprised even me....

I think we are beginning to show just how MUCH AA9 benefits from 6" barrels....

[Desolo]

I REALLY need to get some AA no. 9  thats awesome....

[Intercooler]

If you talk to Kevin Underwood though, he says he can't get the 200gr velocity with #9 and why he doesn't use it.

[nickE10mm]

If you talk to Kevin Underwood though, he says he can't get the 200gr velocity with #9 and why he doesn't use it.

I tend to agree when we're talking about 4.6" and shorter barrels.  But from what I've seen, AA9 likes to take a 6" barrel and really wring it out....

Every powder seems to have a "niche" where it "shines" but most also have a downside.

Blue Dot:  GREAT accuracy, decent full power velocity, temperature sensitive?, scary at high pressure, huge boom, huge flash, meters pretty well
Power Pistol:  good accuracy, great medium power velocity with heavy bullets, high velocity with lighter bullets, big bright white flash, meters great, VERY economical
AA7: GREAT accuracy, great accuracy for medium / warm loads in 10mm but it won't push heavier bullets very fast (if it would it would probably be my favorite overall), no flash, meters like water, economical
AA9: GREAT accuracy, will push lighter bullets fast but really shines with long barrels and HEAVY bullets 180 and especially 200-230gr bullets due to its extremely slow burn speed, very LOW pressure with these heavy and fast bullet combinations, no flash, NOT very  economical with charge weights and powder cost itself, meters like water
Longshot:  great accuracy, pushes light AND heavy bullets VERY fast (by going over book-loads mostly), meters decently, flash isn't too bad, heavy recoil and loud blast, VERY economical
800X:  good accuracy, velocity KING over wide spectrum of loads (mostly over book), some flash, decently economical, MUST HAND WEIGH CHARGES, IMHO velocity you can get isn't really worth it with all of the hand weighing unless there are no other options available.

[Intercooler]

Good info! I think #9 would be my sole powder.

[nickE10mm]

Good info! I think #9 would be my sole powder.

I like to keep a good target / plinking level powder like W231/HP38 (favorite) or even WSF. 

For the hot stuff I like AA9 (new favorite) and Longshot.

I can use any of the others in a pinch for almost anything.... but we're talking about "favorites" so those are mine.

[Driftwood]

After running these AA#9 rounds through the chronograph, I definitely found my hunting load.  The only problem I have with using AA#9 is that it disappears too fast.  With as hard as it has been to find, I'll limit it to hunting loads only...at least until I can find more.  I have several lbs of Blue Dot and like to use that as my plinking loads.  It doesn't meter well, but if I stick to mid range loads, I don't worry about it much.  I've shot WSF out of both my 9mm and 10mm guns.  Shoots nice, but dirty.  Lately, I have come into a large supply of Auto Comp.  I really like it in the 9mm.  I have yet to load any 10mm with the Auto Comp, but plan to soon.