XMIKE

Correct

You know as well as I know that not all gun powder is created equal or has the same application. I'm saying is that to make over 1,300 fps I need 7.5 to 7.9gr. of HS6 and I estimate the barrel pressure to be within 31,867 to 35,000 psi... That's all, I told you how I determined barrel pressure using science and you want to go on and on. If you prefer another powder or you don't believe 9 Major is possible or safe with any powder, please cut to the chase.

Based on my crono 1,362 fps and back calculating the pressure it's at 35,000 psi for 7.9 gr. of HS6. I have no way to measure pressure other than a calculator or a spread sheet. If we were to say the projectile looses "x" amount of velocity before it breaks the crono,, I could understand that. However I believe that it would only be incremental. At this point I would say it's a great science experiment for someone, thanks for digging into the manuals and responding. As with any new load we all need to do our homework.

Open1215 I only run a 4 port Wolf barrel and no comp. on the Glock 34. I like the Carver comp and I would definitely consider it on a different set up. superdude If you have a barrel pressure of 62,248 psi pushing a 124 gr. projectile that equates to a velocity of 1,817 fps in a Glock 34 with a 5.31" barrel... My crono's were no where near that, they were as expected above 1,300 fps. This is Newtons second law of motion, F=ma. If the mass of an object is held constant, increasing force will increase acceleration.

Actually if you have Projectile Weight, Bore diameter, Barrel Length and Projectile Velocity you don't need anything else to determine Barrel Pressure. We didn't address the question of Projectile Energy yet, so lets drag that in as well, all of the above can used to calculate it as well. If I want a Projectile Velocity of 1,300/fps I can choose many different charges, OAL and even argue some case for hard or soft, Pistol or Rifle primers to get there. For the sake of the above physics none of that matters. As noted in the chain above, what has worked to get me into that 1,300 ft/sec.and plus range is Hogdon HS6 at loads of 7.5 to 7.9gr. OAL 1.150 at an elev. 2490 ft... Once again these are my loads and no has to, or is expected to try them. If you have supported reference information that says the calculations I posted are out to lunch feel free to correct me. I'm always interested in being educated by knowledgeable people.

superdude You can download an xls spread sheet from Close Focus Research www.closefocusreaserch.com, credit to the developer Sam Rahab. It's called "Calculating Barrel Pressure and Projectile Velocity in Gun Systems" and it is the best resource I have found for doing these calcs. The SAAMI pressures are SAAMI pressures www.saami.org no need to say more. As far as doing the math is concerned start with the barrel length as published for your firearm, then use the max. SAAMI pressure for the cartridge, that will lead you to the calculated fps... Power Factor PF is projectile weight x fps divided by 1000. The actual loads shown are the ones that I have used and chronographed using HS6, 9mm brass, 124 Cam-Pro FCP (Full Copper Plated) RN and my Caldwell Precision Premium Crono. If you choose to use same that's totally up to you,

If you are like me and intend on reloading 9mm Luger brass then this is important. SAAMI Cartridge Pressures are key with 9mm Major, here's the quick math. For 9mm Luger the SAAMI Maximum Cartridge pressure is 35,000 psi and at that pressure the max 124gr velocity in a stock 5.31" (Glock 34) is 1,362 ft/sec for a PF of 169... At 1,335 ft/sec the SAAMI cartridge/barrel pressure is 33,606 psi and works out to a PF of 165. If you shoot IPSC where Major is 160PF that works out to 1300 ft./sec actually 161PF with a SAAMI Pressure of 31,867 psi. HS6 will get you there with an OAL of 1.150" and loads between 7.5 and 7.9... Note - 8.0 gr. is too hot with SAAMI pressures >36,000 psi. Start at 7.3 gr. and work up from there. Also try a ported barrel for better control, I run a Wolf 4 port and I find it to be excellent in my Gen 4 34.

Hodgon recommends 1.10 OAL and that is what I shoot in both my Gen 4 34 and my CZ Shadow. No issues and average of 924 FPS with 3.5 gr of Titegroup, works out to a PF of 135.8. Your problem is easy to fix, just rerun the cartridges to the lower length and your done.