Alliant STEEL Powder in 10mm MT CCU Carbine w/ 220 gr Xtreme Plated

[PointBlank82]

Hello all, just joined the 10mm fold.

I scored cheap 220 gr Xtreme Plated bullets and am going to work up some loads for my new (to me) Mech-Tech 10mm Carbine.

Has anyone here used Alliant's STEEL powder in a longer barrel, heavy bullet combination? I read some reports by MCNETT from about 10 years ago and that particular powder didn't work quite as well as AA #9 out of a standard pistol barrel, but I haven't found anything in my google searches on how it performs in a 16" barrel.

My local ACE has about 10 lbs of the stuff for $30/lb, and it's one of the few handgun powders still available online ($19/lb!), so I'm thinking of grabbing a bottle for testing.

FYI, I have an RCBS Chargemaster so will be single loading all of these.

I'm planning on using once-fired Star-Line brass with Winchester Large Pistol primers (they say good for standard AND magnum loadings??).

Any advice would be appreciated.

[The_Shadow]

PointBlank82, Welcome to the forum!  Well I haven't used Alliant Steel, but those that have tested with it posted the data over at GlockTalk; here is the link...http://www.glocktalk.com/forums/showthread.php?t=179347  Other than this data they tested (which has no pressure values) you would be working blindly as they did even with a chronograph.

Be very careful to read through the information with a fine tooth comb, sometimes not all the info is in their data, some have miss read the data where McNett was using a Thompson T/C 10" closed and lock breech gun for testing and this data would not be suitable for semi auto pistols.   Also some powders are too bulky for the powder space left inside under the bullets.

If you haven't purchased the powder as of yet, you may want to hold off and look for LongShot, Power Pistol, Blue Dot, AA#7 or #9, for better performance powders.  If you don't mind hand weighing your charges IMR800X is a good choice too.
All of these have printed data and pressure values for them.

Good luck!