I am relatively new to the sig, been reloading and shooting it for almost a year now. For what its worth-
1/2- No problem with stock barrel, shoot reloads in my G32C with stock barrel, Do have a KKM for my G27 converted to 357 SIG. Fired cases are ok to reuse in reloading, I beleive the 40 cal glocks have the issue of unsupported cases being an issue. Havent had any problems with stock barrel and reloading brass fired from the stock barrel.
3- I use the dillon carbide die set, uses a separate taper crimp die,pretty typical for progressive press. Lots of people use the lee factory crimp die, use the right bullets (those designed for 357 sig) and you will be ok using taper crimp die. Correct die adjustment is very important in order to avoid bullet setback issues. WHen setting the die I check the neck tension with bathroom floor scale as indicated in "Petes Page" mentioned above. I second Haze's advice. Look up the page, great info there. I have no experience with crimping seating this caliber in same station. I have used redding dies in other calibers and really like them, just never used their 3 die set for the 357 SIG.
4. I have been using Alliant Blue dot with Montana Gold 125 FMJ Sig bullets. Not married to it, but has good volume, no issues with full burning, very clean, some dont like the flash with compensated barrels, I dont really notice it, you can get good FPS from it, and meters well, my ammo has been very accurate. I have no experience with the AA7.
5. Have no experience with Georgia Arms ammo.
I think you will find that the sig is very interesting cartridge, has great performance and is worth the little bit of extra effort learning about it. Once you get set up it is a snap to reload. Absolutely love the cartridge. I think you will like the MG 125,s. CK out the older posts on the site, their 124 hps work well too.
Glock Certified Armorer
Last edited by leeward419; 11-30-2010 at 18:51..