Petrov Posted June 14, 2017 Share Posted June 14, 2017 So I shot some of my 9mm loads over a chronograph and I shot 3.6 grains of solo 1000 over 135 grain bayou round nose bullet. My velocity was 812 fps average. I shot 18 rounds over the chrony and my extreme spread was over 50fps? What could cause the spread so wide? Link to comment Share on other sites More sharing options...
MemphisMechanic Posted June 14, 2017 Share Posted June 14, 2017 Severe OAL variation, differences in case volume, and most importantly, the variation in charge weights with each powder drop. Those are the likely culprits. What was the standard deviation of your ammo? (Google "standard deviation calculator" and enter your velocities) 20 is horrible. 15 is pretty meh 10 is where we begin to be happy 5 is exceptionally consistent ammo. Link to comment Share on other sites More sharing options...
Petrov Posted June 14, 2017 Author Share Posted June 14, 2017 Loading this on dillon SDB mixed brass. My friend chrono has the numbers saved i will ask him. Gotta figure out what the problem is now. Going to drop a buttload of charges and check for consistency Link to comment Share on other sites More sharing options...
858 Posted June 14, 2017 Share Posted June 14, 2017 Mixed brass means mixed case capacity and variation in pressure. Never say never but I doubt you'll ever get great consistency with mixed range brass. So long as I make PF and it's accurate I don't care, pistols are not generally shot at distances that 50fps ES is noticeable. I'd also guess that if you're using mixed range brass accuracy isn't a limiting factor either. If you need extremely consistent ammo I'd start with either new or brass that is all from the same lot and then work up the OCW. Link to comment Share on other sites More sharing options...
CZ85Combat Posted June 14, 2017 Share Posted June 14, 2017 Your powder charge is to low. Powder is not burning efficiently due to low pressure. you need to get your fps up to about 900 or more. Link to comment Share on other sites More sharing options...
wrench459 Posted June 15, 2017 Share Posted June 15, 2017 Funny how things work out. Got a new chrono last week only had time to run a few rounds across it due to weather and life. .177..7.4gr springer rifle 930 fps 886 fps 964 fps 956 fps Av vol 934 Es 78 Sd 35 The 886 reading is because I oiled the chamber so I deleted the shot from the string. Av vol 950 Es 34 Sd 17 Link to comment Share on other sites More sharing options...
resortboarder Posted June 15, 2017 Share Posted June 15, 2017 (edited) Different bullet profile seems to give me different ES's. RN or RNFP give me consistent <10 FPS readings. SWC's seem to give me inconsistent velocitys up to 60 FPS. Same gun, powder, bullet manufacture &, same press. Not sure if others have noticed this too. Maybe try another bullet profile? Edited June 15, 2017 by resortboarder Link to comment Share on other sites More sharing options...
olstyn Posted June 15, 2017 Share Posted June 15, 2017 1 hour ago, CZ85Combat said: Your powder charge is to low. Powder is not burning efficiently due to low pressure. you need to get your fps up to about 900 or more. Almost certainly this. Even at 900 FPS, it's still only 121.5 PF. (The OP's stated average is 109.6 PF!) The OP hasn't said that s/he is loading for competition, so meeting 125+ may not be the goal, but my understanding has always been that at super low charge weights, lots of powders can exhibit less than consistent behavior, and frequently burn less cleanly as well. Link to comment Share on other sites More sharing options...
Petrov Posted June 15, 2017 Author Share Posted June 15, 2017 its solo 1000 would .2 grains get me to 130PF? Link to comment Share on other sites More sharing options...
olstyn Posted June 15, 2017 Share Posted June 15, 2017 130 PF with 135 grain bullets = 963 FPS. I'm not personally familiar with Solo 1000, but I doubt that .2 grains more of just about any powder would get you +150 FPS. Link to comment Share on other sites More sharing options...
MemphisMechanic Posted June 15, 2017 Share Posted June 15, 2017 You're going to want 3.6gr of Solo1000, give or take. I didn't notice the velocity on your initial post or my first reply would have been "you're loading so light the powder isn't burning consistently! My load data with lots and lots of Solo1000 found in there: Link to comment Share on other sites More sharing options...
mikeinctown Posted June 15, 2017 Share Posted June 15, 2017 Given the data from the first post and the data that MemphisMechanic posted, I would load some with 3.8, then some with 3.9, and again some with 4.0 to see what happens. I would also pull a bullet you've made to see if you aren't over crimping, and even make a dummy round to see if there is enough crimp by pushing the case into a hard surface to see if you are getting setback. Link to comment Share on other sites More sharing options...
zzt Posted June 15, 2017 Share Posted June 15, 2017 Across the board I have found that light loads for a given caliber are problematic. Some powders are better than others at light loads. Some calibers are more prone than others to higher ES/SD with light loads. Any way you slice it, 109 PF is too low in any caliber for a consistent burn. If you want a light load to perform better, change to something like Alliant e3 powder. That will go a long way toward improving shot to shot consistency. S1000 is a terrific powder, and I use it. However, it does not like light charges. It is entirely possible to get good consistency with mixed range brass. For example, my Limited 172PF load is always between SD 4 and SD 7, and I use a mix of Police Range brass, local indoor range brass, and stuff I buy. I don't sort headstamps or anything. I just clean them and load them. Link to comment Share on other sites More sharing options...
Petrov Posted June 15, 2017 Author Share Posted June 15, 2017 Thanks guys, checked my SDB, throws consistent powder, no bullet setback, I checked on the bullet before to make sure that there is no overcrimping since I use coated bullets. Will try a higher charge and report back here. I appreciate all the help. Link to comment Share on other sites More sharing options...
MemphisMechanic Posted June 15, 2017 Share Posted June 15, 2017 (edited) 2 hours ago, mikeinctown said: Given the data from the first post and the data that MemphisMechanic posted, I would load some with 3.8, then some with 3.9, and again some with 4.0 to see what happens. I would also pull a bullet you've made to see if you aren't over crimping, and even make a dummy round to see if there is enough crimp by pushing the case into a hard surface to see if you are getting setback. Given that he's loading a heavier bullet than my 130gr data, my suggestion would be a 3.6, 3.8, and 4.0gr ladder if using a 135gr Bullet. I think 3.8 would probably be close to the 130-133 power factor neighborhood with that Bullet and charge weight. Personally I load to 133-135 pf these days. Cycles the gun and hits steel a bit more aggressively, tends to be more consistent in velocity. I also find it's typically more accurate than something just barely legal like a 126 PF load. Youll shoot just as well and as fast with 135PF ammo as you will with 125.1 Edited June 15, 2017 by MemphisMechanic Link to comment Share on other sites More sharing options...
mikeinctown Posted June 15, 2017 Share Posted June 15, 2017 1 minute ago, MemphisMechanic said: Given that he's loading a heavier bullet than my 130gr data, my suggestion would be a 3.6, 3.8, and 4.0gr ladder if using a 135gr Bullet. He is already loading 3.6 and the fps is way slow for him, (812 average) which is why I suggested going up to at least 3.8 and others had suggest 3.8 or 4.0. Link to comment Share on other sites More sharing options...
Hi-Power Jack Posted June 15, 2017 Share Posted June 15, 2017 Not a problem, unless accuracy is not there .... Link to comment Share on other sites More sharing options...
adamge Posted June 16, 2017 Share Posted June 16, 2017 11 hours ago, Petrov said: Thanks guys, checked my SDB, throws consistent powder, no bullet setback, I checked on the bullet before to make sure that there is no overcrimping since I use coated bullets. Will try a higher charge and report back here. I appreciate all the help. IMO unless you have a scale that is much better than the average reloading scale, there is no way to definitely conclude that your press is throwing consistent powder amounts. A scale that only shows to the 0.1 grain isn't precise enough to take the charge consistency out of the equation for why your velocities are spread that much. I have a similar problem with my loads... Shadow 2, 147grain truncated plated, 1.097" ± 0.004, set for 4.25 grains of Silhouette, I see numbers like... 923 893 915 914 915 902 913 903 887 911 897 899 883 888 I've also found that trying to chrono subsonic loads is tricky. What's helped me is moving farther away from the chrono, I'm at about 15' now. Link to comment Share on other sites More sharing options...
Hi-Power Jack Posted June 16, 2017 Share Posted June 16, 2017 I have to agree with Adam ^^^^ Link to comment Share on other sites More sharing options...
Petrov Posted June 16, 2017 Author Share Posted June 16, 2017 I'm using the labradar Link to comment Share on other sites More sharing options...
MemphisMechanic Posted June 16, 2017 Share Posted June 16, 2017 10 hours ago, mikeinctown said: He is already loading 3.6 and the fps is way slow for him, (812 average) which is why I suggested going up to at least 3.8 and others had suggest 3.8 or 4.0. Damn. I read his post twice and I swear I read "3.2" both times. Derp. Link to comment Share on other sites More sharing options...
9x45 Posted June 16, 2017 Share Posted June 16, 2017 (edited) OP, you have to use the same head stamp brass, measure (bullet diameter) and weight each, measure and weight each powder charge, and measure each OAL. Solo 1000 runs about +/- .1 grains out of a Dillon. And stay 20 feet back from the chrono for loads less than 1,000 fps. Then you should be in the 5-10 fps range. But all that is just statistics, as long as you meet the minor floor and your groups are tight. Edited June 16, 2017 by 9x45 Link to comment Share on other sites More sharing options...
Hi-Power Jack Posted June 16, 2017 Share Posted June 16, 2017 3 hours ago, 9x45 said: as long as you meet the minor floor and your groups are tight. That's ALL that matters Link to comment Share on other sites More sharing options...
Petrov Posted June 19, 2017 Author Share Posted June 19, 2017 Bumped up my charge to 3.8 grains of solo 1000 and now I am getting good numbers and it burns REALLY clean, night and day difference. I also noticed something that might have been the culprit. My powder measure adjustment screw has been walking clockwise, it likes to wander. Going to get one of those clicker knobs to keep it still. Link to comment Share on other sites More sharing options...
9x45 Posted June 21, 2017 Share Posted June 21, 2017 On 6/19/2017 at 8:21 AM, Petrov said: I also noticed something that might have been the culprit. My powder measure adjustment screw has been walking clockwise, it likes to wander. Going to get one of those clicker knobs to keep it still. Never, ever, never seen that on any Dillon powder hopper. Link to comment Share on other sites More sharing options...
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