Velocities for the loads I fotografed are posted on the pics.
http://jeffreybehr.zenfolio.com/p548446203
I bought 8 pounds of LS for my .40 for the same reason, but then I switched to Universal for my .40-cal. PD loads.
Nice pictures and your results were as expected for LongShot. The reason you were getting such a large flash in your 10mm LongShot load is the 155 grain bullet is too light to burn all the powder in the barrel with this slow powder in this large of case. I use 9.4 grains of LongShot with 180 grain XTP's to get 1325 fps and I get no flash visible from the firing position. Were you using magnum primers? They are recommended for LongShot.
In my G20 with the factory barrel, I started getting smilies at 9.5 at 1350fps at the rate of about 1 out of 5. It will go a lot faster and handle a bit more powder. I don't know who said it won't go faster as it goes right on up. I never tried any more than 9.6 grains as it was bulging 2 out of 5 in the stock barrel. I switched to a Lone Wolf barrel and no more bulges but this barrel isn't as fast as the Glock barrel. I recently started using a Dillon so I backed up the load to 9.4 for safety and it clocks 1325 in the Lone Wolf barrel.
My magic 10mm Load was given to me by Mike McNett from Double Tap a couple years ago.
180 grain XTP
Starline Brass
9.4 grains of LongShot. He actually used 9.5 to get his advertised 1350fps. I backed it down just to add a small margin of safety.
CCI-350 primer
1.260" OAL
This is my go to load for 10mm. It yields 1325 fps and 702fpe but don't recommend it in the stock barrel. I like it for how clean and powerful it burns with minimal pressure and almost no visible muzzle flash.
I just looked and noticed Mike is no longer selling this load so he may have concluded the same thing I did is is was a bit hot for the factory barrel. It is perfectly safe in the Lone Wolf barrel. Accuracy is excellent. On a good eye day I can hit clay pigeons pretty regularly at 100 yards.
I love LongShot and use it exclusively for all my auto pistol needs 9mm, 357Sig, 40S&W and 10mm.
My 155XTP LongShot load is a huge success with almost no flash and extremely clean burning while providing over 500FPE out of a G23. I sell the heck out of this load.