N320 to make major in 45 ACP?

[Marv Z]

I recently cronoed my IDPA CDP round before the state match this weekend. I was at 4.8 gr of N320 with a 230 Zero HP at 1.230. To my surprise, I was only at 650 fps average for a PF of 150. Went to 5.0 and got up to 700 fps. Had to go all the way to 5.2 to get around 750 fps for a PF of 172. This sounds high to me. Going thru a SA TRP 5" barrel. Tilted the gun up to get the powder to the rear before all testing. Most of the loads I've heard of are around 5.0 to make major. No signs of pressure. Any input? I'm wondering if I have a slow batch of powder or something. Thanks!!!

[ZombieHunter]

I chronoed 4.9 gr of N320 with Zero 230 FMJ at 1.25" in a 5" bbl and got 738 fps on average in a 7 shot string. If you're not seeing any major case bulging, I wouldn't worry about it too much. It is possible your batch could be "faster" than others (resulting in slower speeds). I quite often end up going slightly over on faster powders to accommodate for different barrels. Clays is a good example of this. Just watch for pressure signs and read what the chrono tells you and use common sense and you should be fine.

[motosapiens]

I got 171 with 5.1 of n320. LIke you, I also tried lower loads and worked my way up.

Coming from shooting 40, I'm finding that .45 wants more crimp in order to burn well and have consistent velocities. I haven't tried n320 again since I figured that out (been using clays), but the loads with clays went up about 5%-8% in velocity with more crimp. I went from just barely kissing the rim and removing the flare, to about 1/2 turn on a lee FCD. I wouldn't stress. Put as much powder as you need to make PF. you're in no danger at that level of n320, regardless of what books say. I tested some SD loads recommended by bill wilson that were WAY above book max, and just from looking at the brass and the behavior of the gun, I would have to say it was significantly less pressure than the winchester factory rounds that my co-workers are issued.

Also remember that some people are shooting lead or moly. I found that moly bullets needed almost 10% less powder to get the same velocity as my plated bullets. It's possible the real jacketed bullets like the zeros are even slower.

Edited September 5, 2013 by motosapiens

[leftee]

Based solely on my own experience I find that I obtain more consistent results with N320 if there is less vacant space in the case. The longer the OAL the greater the deviation. I've been using 230grain Berrys, Zero FMJ, and Zero HPs. The Zero HPs are loaded to an OAL of 1.214 and have been the most consistent. My results can be found in this thread...

http://www.brianenos.com/forums/index.php?showtopic=177953&hl=%2Bleftee#entry1966618

Marv Z, if you want to decrease the charge, I suggest you shorten the OAL.

Edited September 6, 2013 by leftee

[leftee]

In case you think loading the JHP to 1.214 seems short you might want to take a look at this....

[jstagn]

How is the FELT recoil (45acp 230gr plated) with both making major of Clays vs. N320?