Krag Posted June 1, 2016 Share Posted June 1, 2016 I just switched to using TiteGroup in my customized Springfield 4.5 XDM and am trying to work up a decent USPSA load. The best so far is a 180 gr. Remington FMJ bullet and 4.7 gr. of TiteGroup which gives an average P.F. of 180.4. Do you think this is too high for serious competition? How low would you suggest I go to be safe? Link to comment Share on other sites More sharing options...
mosher Posted June 1, 2016 Share Posted June 1, 2016 Average velocity minus 1 standard deviation needs to be above 165PF. Link to comment Share on other sites More sharing options...
motosapiens Posted June 1, 2016 Share Posted June 1, 2016 generally in the 170-175 area is enough cushion tht you don't have to stress about bad luck or a wacky chrono or getting a light bullet pulled. Anything above 175 I personally would reduce, but it really doesn't make as much of a difference as you might think. Once i discovered my splits were near identical between major and minor, I stopped worrying about and extra 3-4 pf here or there. Link to comment Share on other sites More sharing options...
Vesteroid Posted June 1, 2016 Share Posted June 1, 2016 I just switched to using TiteGroup in my customized Springfield 4.5 XDM and am trying to work up a decent USPSA load. The best so far is a 180 gr. Remington FMJ bullet and 4.7 gr. of TiteGroup which gives an average P.F. of 180.4. Do you think this is too high for serious competition? How low would you suggest I go to be safe? just out of curiosity, what OAL are you loading that to? Link to comment Share on other sites More sharing options...
Hi-Power Jack Posted June 1, 2016 Share Posted June 1, 2016 I fire 20 rounds thru the chrono and want ALL 20 to make 165 PF (they usually average around 173). Link to comment Share on other sites More sharing options...
Woodsk Posted June 2, 2016 Share Posted June 2, 2016 I try to load to ~171 stays safe and I can't really feel a difference between that and 165 Link to comment Share on other sites More sharing options...
RecoilJunkie Posted June 2, 2016 Share Posted June 2, 2016 Mine are averaging around 170, loaded short, 4.2gr titegroup. Link to comment Share on other sites More sharing options...
enzo357 Posted June 2, 2016 Share Posted June 2, 2016 170-172 is very safe Link to comment Share on other sites More sharing options...
zzt Posted June 2, 2016 Share Posted June 2, 2016 The PF you need to be safe really depends on how consistent your load is. If your SDs are high, you'll need more PF to make up for the inconsistency. If they are good, you can go lower. For example: my Limited load chrono SDs for 10 and 20 shot strings average at SD 6.5. With SDs that good, I could shoot 167PF and the slowest bullet in the string would be 5fps faster than needed to make 165PF. However, I choose to load to 172PF. That means that the slowest bullet in the string is 36fps faster than needed. I don't really notice the difference in recoil, so I'd rather have the larger margin. Even though the chronos are supposed to be calibrated using reference ammo, chrono technique plays a part as well. One guy at my club shaves it close. He usually gets away with it. At one match he chrono'd just under and had to shoot minor. It ruined his day. Why take the chance? My rule of thumb is if you cannot get SDs consistently under 12, change your load. Personally, if it isn't in single digits, I'm not happy. Link to comment Share on other sites More sharing options...
Krag Posted June 2, 2016 Author Share Posted June 2, 2016 (edited) Kylelee: What pistol and length of barrel do you use? Edited June 2, 2016 by Krag Link to comment Share on other sites More sharing options...
mach1soldier Posted June 2, 2016 Share Posted June 2, 2016 How consistent your bucket weight is matters quite a bit in my eyes. Plated and lead vary a few grains which can drastically affect your PF. I always shoot for 170 average and all shots above 165 PF. Link to comment Share on other sites More sharing options...
fishsticks Posted June 2, 2016 Share Posted June 2, 2016 Very informative thread on this topic here: Reloading to Meet Power Factor with Confidence! https://r.tapatalk.com/shareLink?url=http://www.brianenos.com/forums/index.php?/topic/229005-Reloading-to-Meet-Power-Factor-with-Confidence%21&share_tid=229005&share_fid=16618&share_type=t Link to comment Share on other sites More sharing options...
Krag Posted June 2, 2016 Author Share Posted June 2, 2016 Veteroid - 1.135" I just loaded up some with 4.3 and 4.5 grs. of TiteGroup and will chrono them tomorrow. Link to comment Share on other sites More sharing options...
jwhittin Posted June 3, 2016 Share Posted June 3, 2016 Here is the link. Forget about PF, what's your SD? http://www.brianenos.com/forums/index.php?showtopic=229005 Link to comment Share on other sites More sharing options...
jwhittin Posted June 3, 2016 Share Posted June 3, 2016 Average velocity minus 1 standard deviation needs to be above 165PF. If you do this and use 165, your chance of failing chrono is about 44%. Link to comment Share on other sites More sharing options...
motosapiens Posted June 3, 2016 Share Posted June 3, 2016 Average velocity minus 1 standard deviation needs to be above 165PF. If you do this and use 165, your chance of failing chrono is about 44%. with the first 3 rounds. Now go calculate what the chances are for 7 rounds and report back to the group please. Link to comment Share on other sites More sharing options...
jwhittin Posted June 4, 2016 Share Posted June 4, 2016 Your average velocity is always determined using 3 rounds, never 7. If you fail the first attempt using 3 rounds, the 3 highest measurements are used out of 6 rounds. If you still fail to meet PF, you have a choice of using best 3 out of 7 rounds or recalc based on a new bullet weight. I much prefer to pass first time and not have to worry about it. Link to comment Share on other sites More sharing options...
PatJones Posted June 4, 2016 Share Posted June 4, 2016 I can't feel a change of 5 power factor. I don't flirt with the minimum required. Link to comment Share on other sites More sharing options...
teros135 Posted June 4, 2016 Share Posted June 4, 2016 I've heard that, statistically speaking, your average chrono'd velocity should be at least two standard deviations above the PF floor. For instance, with .40 cal 180 gr, 916 is the floor for 165 PF. Your loads are chronoing with a SD of 10, so you need to be at least 936, which is a PF of 168. For .40 major, I go for about 170-172 with SD 10 or less and all rounds reading 170 or above. (With a SD of 15, you'd want to load to 946 fps and 170 PF.) Don't forget to WEIGH THE BULLETS. Don't just calculate from the bullet weight on the box. A bullet that's off by 1 gr translates into about 1 PF at a given velocity (at least for 180 gr at 946 fps, 147gr 9mm at 884 fps, and 124gr major at 1400 fps). Link to comment Share on other sites More sharing options...
jwhittin Posted June 4, 2016 Share Posted June 4, 2016 Yep, minimum 2SD. Use 2.5 or 3SD if more margin is needed. Link to comment Share on other sites More sharing options...
broadus123 Posted June 4, 2016 Share Posted June 4, 2016 Don't forget the chronograph. Some are more accurate than others. I use competition electronics and have found it to be right on with major match chronys. I load to 172 pf to be safe. Outside temperature also affects some powder. Link to comment Share on other sites More sharing options...
motosapiens Posted June 4, 2016 Share Posted June 4, 2016 Your average velocity is always determined using 3 rounds, never 7. If you fail the first attempt using 3 rounds, the 3 highest measurements are used out of 6 rounds. If you still fail to meet PF, you have a choice of using best 3 out of 7 rounds or recalc based on a new bullet weight. I much prefer to pass first time and not have to worry about it. exactly. sounds like you didn't do your homework, which was to calculate the probability of passing using your best 3 out of 7 rounds (for the sake of this exercise, we can assume that the shooter will choose to shoot rather than weigh the 7th round). Link to comment Share on other sites More sharing options...
Krag Posted June 4, 2016 Author Share Posted June 4, 2016 4.5 grs. of TiteGroup gives me an average P.F of 177.7 out of my XDm and 173.9 out of my Para 16.40. I' going with that. Link to comment Share on other sites More sharing options...
blaster113 Posted June 5, 2016 Share Posted June 5, 2016 I'd shoot for a minimum of 172-175 pf for big matches. I've been to majors where my ammo chronoed 172pf at home then got169pf at the chrono stage Link to comment Share on other sites More sharing options...
teros135 Posted June 5, 2016 Share Posted June 5, 2016 Yep. Mine chrono'd 175 at home & 171 at a recent L2. Link to comment Share on other sites More sharing options...
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