working up a load - how hot should I test

Beau Bo · March 29, 2012, 09:42 PM

I'm working up a load for my CZ. I'm having to reduce the COL quite a bit from what my book load specifies so it will fit.

I'm at a COL of 1.055, using Missouri 125gr LRN (small ball) and W231. I'm starting at 3.2 gr and working up to 4.2 gr.

Question is how hot should I make my loads when figuring out a new load? Should I keep loading rounds with slightly more powder (work up to 4.4, 4.6 etc.) and then, starting low, see how the rounds behave? I guess my question boils down to - when working up a round how do you know when its too hot other than looking for problems with the spent cases. Is there some way to calculate what may be too hot before I hit the range?

Thanks...

dmazur · March 29, 2012, 09:51 PM

Caliber?

Beau Bo · March 29, 2012, 09:56 PM

Sorry - 9mm

ScottRiqui · March 29, 2012, 10:04 PM

Honestly, I quit once I find a charge that cycles my pistol reliably and gives me good accuracy. And since almost all of my shooting is done offhand while standing, the accuracy requirement isn't particularly stringent.

dmazur · March 29, 2012, 10:17 PM

Quote:

I'm having to reduce the COL quite a bit from what my book load specifies so it will fit.

Is the book load for Missouri Bullets 125gr LRN? That bullet profile isn't the same as the typical 115gr LRN. From the Missouri Bullets site, it looks like the bullet has a more blunt profile.

I can't find load data for that bullet on line...

Yes I can. Just took a little more time -

http://thefiringline.com/forums/showthread.php?t=480201

Seems like a good answer in the above thread.

deadwolfarms · March 29, 2012, 10:27 PM

Becouse your col is way short your pressure will be much greater so stay on the low end
I dont have a cz but why must your rounds be shorter do you have an issue with factory ammo

Misssissippi Dave · March 29, 2012, 10:52 PM

Loading that short is going to increase pressure. I think you might be in the right range to start out. You probably should test only those to see what you get before trying to go higher. Anything above 4.4 will probably not be something you want to try or if you do check closely for over pressure signs. At the top end it is probably going to spike on you. I would think you low end probably should be around 3.4 or 3.5 grains to cycle the CZ. I'm guessing you are using a full size 75. I know my 75 compact will allow me to cycle lighter loads then I can get away with in a Beretta or Sig. W231 is normally good for low to mid range loads. I have found using W231 powder I got my best results by finding the lowest amount of powder that I could get good groups with and then adding 0.1 grains of powder to have it burn a little cleaner.

You in the end will be probably the best judge of what works for you. I'm surprised you couldn't get you CZ to work with a 1.100 or 1.120 OAL. I prefer to load as long as I can reliably get the round to cycle my pistols. I know I tend to load a little shorter to make then also cycle in the CZ.

CS86 · March 30, 2012, 08:16 AM

For the 9mm. Has anyone noticed the difference in max loading between hornady and other books? I feel like hornady's max is below max compared to other books. Is it because there bullet can't withstand higher loads or are they shaped different enough to increase pressure more than others?

I find this is hard to decide what I should work up to with different bullets. I've been wanting to work up some Berry's HP. I can't seem to find a work up for Berry's so I use the other books as a reference, but there can be such a gap as to what is max between books.

March 29, 2012, 09:42 PM	#1
Beau Bo Member Join Date: January 1, 2012 Location: Colorado Posts: 24	working up a load - how hot should I test I'm working up a load for my CZ. I'm having to reduce the COL quite a bit from what my book load specifies so it will fit. I'm at a COL of 1.055, using Missouri 125gr LRN (small ball) and W231. I'm starting at 3.2 gr and working up to 4.2 gr. Question is how hot should I make my loads when figuring out a new load? Should I keep loading rounds with slightly more powder (work up to 4.4, 4.6 etc.) and then, starting low, see how the rounds behave? I guess my question boils down to - when working up a round how do you know when its too hot other than looking for problems with the spent cases. Is there some way to calculate what may be too hot before I hit the range? Thanks...

March 29, 2012, 09:51 PM	#2
dmazur Senior Member Join Date: July 5, 2007 Location: Pacific NW Posts: 1,310	Caliber? __________________ .30-06 Springfield: 100 yrs + and still going strong

March 30, 2012, 08:16 AM	#8
CS86 Senior Member Join Date: February 28, 2012 Location: South Dakota Posts: 224	For the 9mm. Has anyone noticed the difference in max loading between hornady and other books? I feel like hornady's max is below max compared to other books. Is it because there bullet can't withstand higher loads or are they shaped different enough to increase pressure more than others? I find this is hard to decide what I should work up to with different bullets. I've been wanting to work up some Berry's HP. I can't seem to find a work up for Berry's so I use the other books as a reference, but there can be such a gap as to what is max between books. Last edited by CS86; March 30, 2012 at 08:22 AM.

March 29, 2012, 09:56 PM	#3
Beau Bo Member Join Date: January 1, 2012 Location: Colorado Posts: 24	Sorry - 9mm

March 29, 2012, 10:04 PM	#4
ScottRiqui Senior Member Join Date: January 27, 2010 Location: Norfolk, VA Posts: 2,905	Honestly, I quit once I find a charge that cycles my pistol reliably and gives me good accuracy. And since almost all of my shooting is done offhand while standing, the accuracy requirement isn't particularly stringent.

March 29, 2012, 10:27 PM	#6
deadwolfarms Member Join Date: November 27, 2011 Posts: 26	Becouse your col is way short your pressure will be much greater so stay on the low end I dont have a cz but why must your rounds be shorter do you have an issue with factory ammo

March 29, 2012, 10:52 PM	#7
Misssissippi Dave Senior Member Join Date: December 5, 2009 Posts: 1,411	Loading that short is going to increase pressure. I think you might be in the right range to start out. You probably should test only those to see what you get before trying to go higher. Anything above 4.4 will probably not be something you want to try or if you do check closely for over pressure signs. At the top end it is probably going to spike on you. I would think you low end probably should be around 3.4 or 3.5 grains to cycle the CZ. I'm guessing you are using a full size 75. I know my 75 compact will allow me to cycle lighter loads then I can get away with in a Beretta or Sig. W231 is normally good for low to mid range loads. I have found using W231 powder I got my best results by finding the lowest amount of powder that I could get good groups with and then adding 0.1 grains of powder to have it burn a little cleaner. You in the end will be probably the best judge of what works for you. I'm surprised you couldn't get you CZ to work with a 1.100 or 1.120 OAL. I prefer to load as long as I can reliably get the round to cycle my pistols. I know I tend to load a little shorter to make then also cycle in the CZ.