9mm Chrony Data [Archive] - Glock Talk

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sourdough44
01-26-2010, 12:04
I set up the chrony for some 9mm loads today. I had previously loaded some light win 231 loads and had a few issues. The bullet I used is a Rainier 'plated' 115 grn RN. I set the COL at 1.10 & 1.09. The gun was a 92fs.

The 1st loads were with a 4.1 grn charge of win 231. I would get a stove-pipe on average every 3-4 shots. I used that charge from the lower spectrum of data from my Sierra manual. I later see the Hodgdon site has 4.3 - 4.8grn win 231 for a 115 lead bullet. I think I would be fine if I bumped up the 231 charge some. Four shots through the chrony averaged 959fps. The data with the 4.3-4.8 lists expected fps 1079 - 1135. Win 231 also gets high marks as a 9mm powder overall. These cases also ejected right next to the gun, one foot over.

My next load was 4.2 of Tightgroup with the same bullet. The Hodgdon site lists a range of 3.9 to 4.3 with a 115 grn lead bullet. This load cycled great, the cases were ejected about 4 ft from the gun. I averaged 1087fps, all within about 40 fps of each other. The 'book' speed for the powder range was 1075 to 1151, so it's right where it should be. The thing about Tightgroup is you have to be very careful with those small powder charges. I weighed each charge and double checked a few times & zeroed the electronic scale often.

I have some older reloads with Bullseye powder to burn up but after that I may just stick with tightgroup. Anyway, just though I would pass it on.

Colorado4Wheel
01-26-2010, 12:38
You really should list your OAL with any data.

ron59
01-26-2010, 13:21
I set the COL at 1.10 & 1.09.

You're slipping, Steve....

Colorado4Wheel
01-26-2010, 14:11
Sorry, I was in a rush.

Interesting, that length is no excuse for poor FPS with the 231.

fredj338
01-26-2010, 14:17
Yeah, you've learned a lesson on load dev. for semiuatos. I rarely use starting data, it just doesn't give good results & isn't any safer than using middle average data form 2-3 sources. Interesting you chose to NOT use starting data w/ a more aggresive/faster powder like TG. Yes OAL does matter & the faster the powder & smaller the case the more it matters.

sourdough44
01-26-2010, 16:04
Yes I did jump up some with tightgroup. I had the data for the 115 grn lead bullets I was using & also saw that the jacketed bullets allowed a higher charge(as usual). So with that in mind & knowing that my starting 231 load was weak I wanted something that would work. I also planned to setup the chronograph, so I wanted something worth testing. The fps was on the lower side of the expected range, so I'm content. The temp was down around 20 or so but the rounds never really had time to cool off much from the basement temps before firing.

I think I am going to pull the rest of the win 231 loads I have that were to weak. Otherwise I'd just be shooting them off to get rid of them. I still think 231 is a great powder, just not at the charge I started at.

fredj338
01-26-2010, 17:28
I think I am going to pull the rest of the win 231 loads I have that were to weak. Otherwise I'd just be shooting them off to get rid of them. I still think 231 is a great powder, just not at the charge I started at.

Another lesson learned. Load only 10rds w/ a new powder charge, then 10 more +0.1gr, then 10 more w/ 0.1gr. Shoo thtem in order, note relaibility, accuracy, unburnt powder, any pressure signs (altthough there should be none at starting to midrange levels). This will save you time & components. After doing your load workup, then you can load 100s.

shotgunred
01-26-2010, 19:30
The thing about Tightgroup is you have to be very careful with those small powder charges. I weighed each charge and double checked a few times & zeroed the electronic scale often.


You just have to get over worrying about it. It is a 9mm thing anyway. With my 40 I can double to quadrupedal load all of my loads. My bet is the 45 is the same thing. My 550 has never needed readjusted after it was set. I just keep the hopper at least half full and tap the side of the hopper to settle the powder when ever I add powder or change the load.

filthy infidel
01-26-2010, 19:36
Shotgunred,

Are you a Pennsylvania native?