Mike in CT Posted April 4, 2012 Share Posted April 4, 2012 I did a couple of searches but was not able to find out the power factor minimums for 3=gun rifle matches. Can anyone enlighten me? I am shooting an AR chambered in .223/5.56 with Montana Gold 55 FMJs Mike Link to comment Share on other sites More sharing options...
Mike in CT Posted April 4, 2012 Author Share Posted April 4, 2012 I think I may have found it, does this look right? Power Factors: US 12.1.12.1 spells them out: Rifle = 340 major, 160 minor Shotgun = 20 gauge minimum I am loading Montana Gold 55gr FMJs with 21grs of H322 and getting a velocity of 2400, so if I do my math 2400 x 55 = 132,000 divide by 100, means I am at 132 PF? Sounds like I am under Minimum. Even my loads with 22.5grs flew at 2500, thus still keeping me under minimum. If my calculations are correct, am I using too light of a bullet? Mike Link to comment Share on other sites More sharing options...
D.Hayden Posted April 4, 2012 Share Posted April 4, 2012 (edited) 2,400 is really slow for a 55 gr bullet Most people are around 2,900 - 3,100 I'd guess Not sure of that powder.. what the minmax is And minor is 150... Edited April 4, 2012 by D.Hayden Link to comment Share on other sites More sharing options...
Mike in CT Posted April 4, 2012 Author Share Posted April 4, 2012 I am shooting out of a stag arms 16" barrel, 1 in 9 twist. The reloading data shows that velocities from 2900 to 3100 from the 'book', but that is probably with a longer barrel. I had better groups with the starting load data, but can try some at the upper end and see if they improve. I do not plan on shooting any regional/national matches but would like to have a 'legal' load just for the heck of it. Mike Link to comment Share on other sites More sharing options...
MarkCO Posted April 4, 2012 Share Posted April 4, 2012 Minimum PF for rifle at USPSA matches is 150. Major 320. Appendix D of Rifle Rules 2009 If it is not a USPSA match, then you have to read the ruleset for the specific match. Most do not specify minimum PF, just minimum caliber. 2400 is REALLY slow, even from a 16", for 55s. 2800 would be what you should shoot for if you are trying to make minor. Link to comment Share on other sites More sharing options...
DyNo! Posted April 4, 2012 Share Posted April 4, 2012 Not many people shoot multigun under the umbrella of USPSA anymore. Outlaw multigun doesn't involve a power factor. Link to comment Share on other sites More sharing options...
MarkCO Posted April 4, 2012 Share Posted April 4, 2012 (edited) Not many people shoot multigun under the umbrella of USPSA anymore. Outlaw multigun doesn't involve a power factor. Wrong and wrong. 5 years ago there were 2 matches. This year there are at least 5 using USPSA rules and there are two matches I know of that are considering using USPSA rules next year. When the 2013 rulebook comes out, it will probably encourage even more. Go read a few rulesets. Superstition for example does have power Factor for the Heavy divisions. Edited April 4, 2012 by MarkCO Link to comment Share on other sites More sharing options...
caspian guy Posted April 4, 2012 Share Posted April 4, 2012 Even if I weren't concerned about power factor from a rules perspective, from a practical perspective i'd still want those going faster if only so they'd have enough retained energy to activate flash targets. Link to comment Share on other sites More sharing options...
D.Hayden Posted April 5, 2012 Share Posted April 5, 2012 Even if I weren't concerned about power factor from a rules perspective, from a practical perspective i'd still want those going faster if only so they'd have enough retained energy to activate flash targets. And cycling reliably.. My 16"... I still run about 2,950 Link to comment Share on other sites More sharing options...
Mike in CT Posted April 5, 2012 Author Share Posted April 5, 2012 So is anyone loading 223 with H322? I read up on the powder and it says it is 'made' for the AR platform. But even at max loads it is likely not going to make PF, and from my tests, the groups were spreading out with the higher powder charges, Mike Link to comment Share on other sites More sharing options...
D.Hayden Posted April 5, 2012 Share Posted April 5, 2012 Looking at their site.. your 22.5 grs at 2,500 fps - seems way too slow. On this same chrono setup.. does it measure a known load accurately? Link to comment Share on other sites More sharing options...
SteveT-NV Posted April 5, 2012 Share Posted April 5, 2012 I think I may have found it, does this look right? Power Factors: US 12.1.12.1 spells them out: Rifle = 340 major, 160 minor Shotgun = 20 gauge minimum I am loading Montana Gold 55gr FMJs with 21grs of H322 and getting a velocity of 2400, so if I do my math 2400 x 55 = 132,000 divide by 100, means I am at 132 PF? Sounds like I am under Minimum. Even my loads with 22.5grs flew at 2500, thus still keeping me under minimum. If my calculations are correct, am I using too light of a bullet? Mike Sierra's Load Data for an AR15 (20in Barrel) - http://accurateshooter.net/Downloads/sierra223ar.pdf - shows the min load for a 55 grain bullet at 22.5 g of H322 giving a MV of 2700 fps. I believe the Powder companies use a universal receiver and a pressure barrel that may not apply to the AR15 rifle. You may be able to carefully use the higher powder weights in the Sierra Data, while of course watching for pressure signs. Though, since your groups were opening up with higher powder weights, you might need to consider a different powder. Steve Link to comment Share on other sites More sharing options...
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