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Re: Factory "Match" loads: weighed or metered?
If you dump factory match ammo powder from a handful of cartridges and compare the charges, you may be surprised at the variation.
If you dump factory match ammo powder from a handful of cartridges and compare the charges, you may be surprised at the variation.
Re: Factory "Match" loads: weighed or metered?
Metered. Last time I checked, 20 rounds of FGMM 168 .308 had variation of +/- .3 gr. and it shoots
Metered. Last time I checked, 20 rounds of FGMM 168 .308 had variation of +/- .3 gr. and it shoots
Re: Factory "Match" loads: weighed or metered?
I pulled down 70rd of FGMM 175gr 308 and weighed each charge. The ES on the charge weight was 0.8gr, OAL variation was 0.032"
When I did the same to 50rd of 168gr FGMM and the charge weight ES was 1.1gr, OAL variation was 0.027"
I pulled down 70rd of FGMM 175gr 308 and weighed each charge. The ES on the charge weight was 0.8gr, OAL variation was 0.032"
When I did the same to 50rd of 168gr FGMM and the charge weight ES was 1.1gr, OAL variation was 0.027"
Re: Factory "Match" loads: weighed or metered?
Clint Smith tells a story where he and Mike Venturino tested "weighed vs. metered". They each reloaded 500 rounds with Mike weighing the charges and Clint metering the charges using a Harrell measure. When they fired them, Clint's shot as good as Mike's loads. Clint did stress that you've got to use good equipment like a Harrell in order to get good results.
Clint Smith tells a story where he and Mike Venturino tested "weighed vs. metered". They each reloaded 500 rounds with Mike weighing the charges and Clint metering the charges using a Harrell measure. When they fired them, Clint's shot as good as Mike's loads. Clint did stress that you've got to use good equipment like a Harrell in order to get good results.
Re: Factory "Match" loads: weighed or metered?
"Clint did stress that you've got to use good equipment like a Harrell in order to get good results."
Not to argue too much with ol' Clint but unless a powder measure's metering chamber changes shape/size during its use I suspect it can be demonstrated that any of them will do an equal job.
What we get with the much more costly powder measures is repeatability of 'return to battery' for the dropped weight by adjusting the chamber by calibrated clicks but not extra - or automatic - better charge repetability after properly setting a measure for desired weight. Fact is, most dropped charge variations come from inconsistant - or improper - measure operation and how well the powder itself meters, not the price or color of the measure.
In fact, it's pretty well known that Lee's very inexpensive all plastic "Perfect Powder Measure" may not be perfect but it's as good as we can get for dispensing consistant charges of coarse grained rifle powders!
"Clint did stress that you've got to use good equipment like a Harrell in order to get good results."
Not to argue too much with ol' Clint but unless a powder measure's metering chamber changes shape/size during its use I suspect it can be demonstrated that any of them will do an equal job.
What we get with the much more costly powder measures is repeatability of 'return to battery' for the dropped weight by adjusting the chamber by calibrated clicks but not extra - or automatic - better charge repetability after properly setting a measure for desired weight. Fact is, most dropped charge variations come from inconsistant - or improper - measure operation and how well the powder itself meters, not the price or color of the measure.
In fact, it's pretty well known that Lee's very inexpensive all plastic "Perfect Powder Measure" may not be perfect but it's as good as we can get for dispensing consistant charges of coarse grained rifle powders!
Re: Factory "Match" loads: weighed or metered?
<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: coldboreshot</div><div class="ubbcode-body">Clint Smith tells a story where he and Mike Venturino tested "weighed vs. metered". They each reloaded 500 rounds with Mike weighing the charges and Clint metering the charges using a Harrell measure. When they fired them, Clint's shot as good as Mike's loads.</div></div>
Isn't the only reason to weigh instead of meter to reduce variation in muzzle velocity? I.e., a lot of things may contribute to overall accuracy, but the sole advantage to weighing loads is just to reduce stdev of MV, right?
(I guess the moral of the comments is that the variation of MV with metered loads is low enough with typical high-velocity rifles to not make a practical difference in accuracy?)
<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: coldboreshot</div><div class="ubbcode-body">Clint Smith tells a story where he and Mike Venturino tested "weighed vs. metered". They each reloaded 500 rounds with Mike weighing the charges and Clint metering the charges using a Harrell measure. When they fired them, Clint's shot as good as Mike's loads.</div></div>
Isn't the only reason to weigh instead of meter to reduce variation in muzzle velocity? I.e., a lot of things may contribute to overall accuracy, but the sole advantage to weighing loads is just to reduce stdev of MV, right?
(I guess the moral of the comments is that the variation of MV with metered loads is low enough with typical high-velocity rifles to not make a practical difference in accuracy?)
Re: Factory "Match" loads: weighed or metered?
It drives me crazy that do all the little things that bench resters do and I still can't make better 308 ammo than FGMM
It drives me crazy that do all the little things that bench resters do and I still can't make better 308 ammo than FGMM
Re: Factory "Match" loads: weighed or metered?
I only weigh every round if it's a powder I can't get to meter consistantly.
But, then again, I always weigh a random case every 8 or 10 for safety reasons.
I only weigh every round if it's a powder I can't get to meter consistantly.
But, then again, I always weigh a random case every 8 or 10 for safety reasons.
Re: Factory "Match" loads: weighed or metered?
<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: dbooksta</div><div class="ubbcode-body"><div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: coldboreshot</div><div class="ubbcode-body">Clint Smith tells a story where he and Mike Venturino tested "weighed vs. metered". They each reloaded 500 rounds with Mike weighing the charges and Clint metering the charges using a Harrell measure. When they fired them, Clint's shot as good as Mike's loads.</div></div>
Isn't the only reason to weigh instead of meter to reduce variation in muzzle velocity? I.e., a lot of things may contribute to overall accuracy, but the sole advantage to weighing loads is just to reduce stdev of MV, right?
(I guess the moral of the comments is that the variation of MV with metered loads is low enough with typical high-velocity rifles to not make a practical difference in accuracy?)</div></div>
Yes that's correct, MV variation doesn't really show up on target that much until you get out to very long distances. That's why 1K yd BR shooters weigh every component, because at 1K yd's even a little variation in MV will show up on target.
<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: dbooksta</div><div class="ubbcode-body"><div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: coldboreshot</div><div class="ubbcode-body">Clint Smith tells a story where he and Mike Venturino tested "weighed vs. metered". They each reloaded 500 rounds with Mike weighing the charges and Clint metering the charges using a Harrell measure. When they fired them, Clint's shot as good as Mike's loads.</div></div>
Isn't the only reason to weigh instead of meter to reduce variation in muzzle velocity? I.e., a lot of things may contribute to overall accuracy, but the sole advantage to weighing loads is just to reduce stdev of MV, right?
(I guess the moral of the comments is that the variation of MV with metered loads is low enough with typical high-velocity rifles to not make a practical difference in accuracy?)</div></div>
Yes that's correct, MV variation doesn't really show up on target that much until you get out to very long distances. That's why 1K yd BR shooters weigh every component, because at 1K yd's even a little variation in MV will show up on target.
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Re: Factory "Match" loads: weighed or metered?
Powder is only a little factor, especially when you get into the h4350's and the h1000 types. Neck tension, case capacity play a big roll in standard deviation.
<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: dbooksta</div><div class="ubbcode-body">According to this BlackGun is producing bulk .223 with "propellant charges to within .015 grains." Hard to believe. Anyone know if/how that's possible?</div></div> I would say this is possible with ball powders. with ball powders you can probably hit the chosen weight 7 or 8 times out of 10 pretty consistent.
Powder is only a little factor, especially when you get into the h4350's and the h1000 types. Neck tension, case capacity play a big roll in standard deviation.
<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: dbooksta</div><div class="ubbcode-body">According to this BlackGun is producing bulk .223 with "propellant charges to within .015 grains." Hard to believe. Anyone know if/how that's possible?</div></div> I would say this is possible with ball powders. with ball powders you can probably hit the chosen weight 7 or 8 times out of 10 pretty consistent.
Re: Factory "Match" loads: weighed or metered?
<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: SWammo</div><div class="ubbcode-body">Powder is only a little factor, especially when you get into the h4350's and the h1000 types. Neck tension, case capacity play a big roll in standard deviation.
</div></div>
If I may ask out of curiousity what would be the difference between "H4350's and the H1000 types" versus other powders? Only ask cause I'm trying to develop some 338lm and 300wm loads with H1000.
<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: SWammo</div><div class="ubbcode-body">Powder is only a little factor, especially when you get into the h4350's and the h1000 types. Neck tension, case capacity play a big roll in standard deviation.
</div></div>
If I may ask out of curiousity what would be the difference between "H4350's and the H1000 types" versus other powders? Only ask cause I'm trying to develop some 338lm and 300wm loads with H1000.
Re: Factory "Match" loads: weighed or metered?
When a factory is running a machine continuously, the powder is continually flowing through the metering device. It's a lot easier to maintain consistency when the powder column doesn't have time to compact over the metering port.
That said, there are many more factors that come into play for accuracy than just powder weight. A lot of factory ammo shoots well because of the heavy "neck tension" they apply, often with a crimp as well.
When a factory is running a machine continuously, the powder is continually flowing through the metering device. It's a lot easier to maintain consistency when the powder column doesn't have time to compact over the metering port.
That said, there are many more factors that come into play for accuracy than just powder weight. A lot of factory ammo shoots well because of the heavy "neck tension" they apply, often with a crimp as well.
