I have been doing a ton of load testing for over a year now but today was the first time using my Magnetospeed chrono vs the cheap Chrony I had been using. First impression of the unit is I really dig it, awesome....for all the known reasons; ease of set-up, use and data collection. I also am confident it is giving me real numbers versus my old chrony that was very sensitive to light and position.
The problem is now I have more questions as to what is going on where-as before I would write it off to a bad chrony day.
I was about out of my last 1-lber of Varget so I switched to a 8lb jug with different lots. I loaded up rounds with the old Varget & known charges and rounds with everything the same minus using the new powder along with some work-up rounds to be sure I was safe.
So, one load was with Berger 168 Hybrids, the other was with 185 Hybrids.
Old Varget/168's gave me my usual fps, new lot gave me 60fps more on average, BUT the primers actually look like they saw less pressure. After seeing this I thought this lot was slower burning.
Then I shot the 185's; identical speeds from both the old and the new lots, primers look the same...?
I am using 6-7x fired Win brass, annealed & BR2 primers. All charges were weighed on a Scott Parker tuned Ohaus and then double checked on a Gempr250. All brass prepared at the same time, the same way. I don't see any correlation to brass weight and FPS, but with that said all the brass was within 2gn empty of eachother. I have done H20 capacity comparisons that proved to me at least that small weight changes don't mean much if any difference in capacity.
The ES and SD of the loads above are all decent FWIW and accuracy was great across the board.
If you made it through all that, I have another question unrelated to powder lot changes.
I have been going back and forth between a Lee collet then gutted Redding Type S to bump shoulder combo versus just using the Redding with bushing and floating carbide button.
Reason being is I can't get consistent neck tension with the Lee but the run-out is less than with the Redding. The force required to seat the bullet when using the Lee is right on the edge of being too little most of the time, maybe a 1lb or less on the press handle at most. I'd say about 20% of the brass requires more force to seat bullets, right inline with what I get when I use the Redding.
Best I can measure, the brass is .001" max under with the Lee where-as the Redding gives .0015" everytime.
The reason I bring all this up is I purposely marked rounds of one of my load sets with high & low neck tension. The high NT gave me about 15 more fps than the low, and seemed more consistent.
I am only shooting at 250-275yds so the loads look good now, question is what will they do at 1k and should I go with the more consistent but increased NT set-up and work on the run-out issue (trying the O-ring trick) or just stick with the Lee and stop over-anal-lyzing everything?
FWIW again, I am not letting the press cam over with the Lee, but I am applying 25-30lbs, holding for a few seconds, releasing, rotating the case 90 degrees and hitting it again.
Sorry for the rambling novel, thanks for any input.
The problem is now I have more questions as to what is going on where-as before I would write it off to a bad chrony day.
I was about out of my last 1-lber of Varget so I switched to a 8lb jug with different lots. I loaded up rounds with the old Varget & known charges and rounds with everything the same minus using the new powder along with some work-up rounds to be sure I was safe.
So, one load was with Berger 168 Hybrids, the other was with 185 Hybrids.
Old Varget/168's gave me my usual fps, new lot gave me 60fps more on average, BUT the primers actually look like they saw less pressure. After seeing this I thought this lot was slower burning.
Then I shot the 185's; identical speeds from both the old and the new lots, primers look the same...?
I am using 6-7x fired Win brass, annealed & BR2 primers. All charges were weighed on a Scott Parker tuned Ohaus and then double checked on a Gempr250. All brass prepared at the same time, the same way. I don't see any correlation to brass weight and FPS, but with that said all the brass was within 2gn empty of eachother. I have done H20 capacity comparisons that proved to me at least that small weight changes don't mean much if any difference in capacity.
The ES and SD of the loads above are all decent FWIW and accuracy was great across the board.
If you made it through all that, I have another question unrelated to powder lot changes.
I have been going back and forth between a Lee collet then gutted Redding Type S to bump shoulder combo versus just using the Redding with bushing and floating carbide button.
Reason being is I can't get consistent neck tension with the Lee but the run-out is less than with the Redding. The force required to seat the bullet when using the Lee is right on the edge of being too little most of the time, maybe a 1lb or less on the press handle at most. I'd say about 20% of the brass requires more force to seat bullets, right inline with what I get when I use the Redding.
Best I can measure, the brass is .001" max under with the Lee where-as the Redding gives .0015" everytime.
The reason I bring all this up is I purposely marked rounds of one of my load sets with high & low neck tension. The high NT gave me about 15 more fps than the low, and seemed more consistent.
I am only shooting at 250-275yds so the loads look good now, question is what will they do at 1k and should I go with the more consistent but increased NT set-up and work on the run-out issue (trying the O-ring trick) or just stick with the Lee and stop over-anal-lyzing everything?
FWIW again, I am not letting the press cam over with the Lee, but I am applying 25-30lbs, holding for a few seconds, releasing, rotating the case 90 degrees and hitting it again.
Sorry for the rambling novel, thanks for any input.
