Plenty of his variables have changed. This is another possible one.
he confirmed the accuracy of his first batch after shooting the new one. Unless his optic setup fixed itself that doesn't make sense.
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same load different groups???
- Thread starter trapoholic
- Start date
Plenty of his variables have changed. This is another possible one.
he confirmed the accuracy of his first batch after shooting the new one. Unless his optic setup fixed itself that doesn't make sense.
Sounds like the combination of your new brass and a new lot of powder, which may or may not be slightly faster is causing your issues.
What's happening with your groups isn't uncommon with two component changes.
sharp shooter
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What scale do you have. I had the same issue once. When I came back to the loading bench I noticed that my 5-0-5 scale had flipped to the next grain on accident. So instead of loading 21 grains, I was loading 22 grains. Went from .5” group to 1” group in my triple deuce.
Bull####. Neck tension is one of the biggest factors when dialing in on a small SD/ES.
You get it, he doesn't. Not worth it if you have to reply over and over. Somehow H110 is only a pistol powder to him and he doesn't see the relevance of an example. He clearly has zero experience with long range shooting or striving for absolute rock bottom spreads. Neck tension is a big deal for precision shooters because it directly affects ballistics.
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Guess I forgot to mention I do crimp everything. Crimp hasn't changed at all. But I'll drop down to 53.5 grains tomorrow and work up. More info is appreciated though. 3" higher than the last batch should have raised a red flag as far as increased velocity goes
Neck tension and crimp are similar but separate. Both affect the time it takes for the bullet to release and begin it's ballistic path. In turn both affect the pressure curve of a given charge of powder, sometimes a lot sometimes a little. A little is a lot to a long range shooter which is why you'll see guys seating bullets at a match to ensure neck tension isn't affected by cold welding and such.
OK, try it with a Labradar and any modern rifle cartridge. Or since you have decades of historical chrony data, post some of it that was fired at the same bench sitting with the exact same load other than neck tension. I will do the same. Again. I predict the mean velocity will not differ.
This is one test I did this summer for fun
2 - 308 Winchesters. 5 bullets each from no crimp all the way to excessive crimps @ 5
The pressure it takes to release the bullet from the case is extremely small compared to the peak pressure therefore has next to no effect on mean pressure or velocity
Peep sights my man. Only use scopes for load development. Which I did for the first batch.
Just a bag of new brass and different lot of powder
Shooting way higher and open groups indicative of higher velocity than the last batch is my conclusion at this point.
It's a rcbs chargemaster lite
So you're using two different lot numbers of the same brass with two different charge weights and getting the same accuracy and velocity? Am I interpreting that correctly?
You have an ES of 20 over 5 shots.OK, try it with a Labradar and any modern rifle cartridge. Or since you have decades of historical chrony data, post some of it that was fired at the same bench sitting with the exact same load other than neck tension. I will do the same. Again. I predict the mean velocity will not differ.
This is one test I did this summer for fun
2 - 308 Winchesters. 5 bullets each from no crimp all the way to excessive crimps @ 5
The pressure it takes to release the bullet from the case is extremely small compared to the peak pressure therefore has next to no effect on mean pressure or velocity
I think we’re done here.
OK, try it with a Labradar and any modern rifle cartridge. Or since you have decades of historical chrony data, post some of it that was fired at the same bench sitting with the exact same load other than neck tension. I will do the same. Again. I predict the mean velocity will not differ.
This is one test I did this summer for fun
2 - 308 Winchesters. 5 bullets each from no crimp all the way to excessive crimps @ 5
The pressure it takes to release the bullet from the case is extremely small compared to the peak pressure therefore has next to no effect on mean pressure or velocity
Once again been there done that.
this is supposed to be a picture of my Chronys but the links aren't working FFS
I shoot over an Oehler with my Labradar beside me. Results are cross referenced and saved.
Your single example hardly trumps my 13000+ chronographing sessions.
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I have. Results above.
Literally 1 shot out of the 6 chrono’d wasn’t the exact same velocity.
