Parabellum Research PBR 180 grain pull-down

[The_Shadow]

Well I'll try this again...the first try was accidently closed before it posted...Got to hate when that happens!

PapaJohn posted a picture of his AA#9 and it sort of confirms what others have said about the powder looking different, having more flattened ball structure as opposed to spherical ball like my 2008 batch.  RamShot Enforcer is very simular spherical ball powder with very simular performance.  You can also reference the burn rate tables for simular powders...http://www.hodgdon.com/burn-rate.html to see what's close.

PBR is using a 180grain FMJ in this loading claming 1302 fps...to fit this in a powder's profile the powder charge for the yield (work being done = bullet weight at velocity), while generally fitting the SAAMI MAP.
Accurate load data 203-1  edition 3.1
No.9 180gr HDY XTP 12.2gr 1,093 fps - 13.5gr 1,242 fps 34,100 psi COAL 1.250"
No.9 180gr RAN HP 12.1gr 1,086 fps - 13.5gr 1,235 fps 35,500 psi COAL 1.260"
No.9 190gr SIE FPJ 12.8gr 1,115 fps - 14.2gr 1,267 fps 35,800 psi COAL1.250"

Now PBR's bullet is a 180gr FMJ, these are physically shorter than a HP design this would allow for slightly more powder at the same pressures.  In the example of the 190 Sierra FPJ (same as FMJ) but it is longer bullet (not by much) than the PBR's 180gr FMJ bullet.  At PBR's 14.6 grain powder charge this limits many powders by weight used for the yield.

I compared this to my samples of Hodgdons H-110 and Winchester 296, they look different, they are slower burn rates, they also require a hard crimp to maintain performance (hard to do with 10mm's with no cannelure and headspacing on the case mouth). 
Winchester load dat shows this for 296...296* 180JHP 12.6grains 990 fps 22,400 psi
*Note: 296 powder is considered to be one of the best powders for use in magnum handgun cartridges. Please refer to page
for recommended primer and use a very heavy crimp. Failure to follow this procedure could result in poor ignition and/or
squib loads under extreme circumstances, particularly in loads where less than 90% of the available powder space is being
used (low loading density).

ADI shows a powder (AR2205) in their load tables that might fit, but this is an Austrailian powder and I have never seen any yet.

So inconclusion, the podwer has to fit the profile for the amount of powder being used and the work being done and the SAAMI MAP.  AA#9 fits this situation.

[The_Shadow]

McNett, of Double Tap, tested some Alliant Steel in 10mm, this is slightly slower than the AA#9 powder and might be a close fit to the profile...I don't have any to compare obut the pictures posted by REDLINE clearly show it is not the stuff.  However as a handloader this much powder being used for the work achieved isn't ecconomical for me to use...

[REDLINE]

I believe I'm satisfied that it's either No.9 or Enforcer.  I don't believe any other posibilities exist that would fit all the criteria we know.