For those that doe seating depth tests at the bench how do you account for change in pressure as you seat the bullet deeper?
Anybody reload at the range?
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VICTORNTN
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villagelightsmith
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Some days I'll take a half dozen perfectly matched brass, a hand primer, a hand press, micrometer dies, calipers, a micrometer, a sheaf of targets, a chrony and a scale. Ears, plugs, and a thermos. There are a thousand things I'd like to know, and this is the way to learn them.
I have loaded at the range for years. My commute was about 2.5hrs. round trip, the cost of fuel and time savings will justify the purchase of a few pieces of gear (that I would have purchased anyway). I use a K&M arbor press and wilson seating dies to seat bullets in already prepped brass. If there is no shelter available to use your scale, you can store previously weighed-at-home powder charges in blood vials or small glass bottles (both available on AZ) and load those into brass as needed. I have seen other guys use an old aquarium or homemade plexiglass case to keep their scale out of the wind. A Harrell's powder measure and Harrells press are nice to have for range loading as well. Hope this helps.
hesse
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Yes we can And do but the range is out the back door which allows for quick adjustment and barrel cleaning. I would hate to have to travel to go to the range when we try work up loads
Well the only thing I do when I do the ladder test is I load some bullet seating tests load three at each height with one charge combination, but I understand the time issue. but with wind at the range, chance of losing primers, dropping powder, etc. just take my time and realize it is part of the process and personally would never load at the range.
I still live rural, surrounded by several hundred acres of farm and hardwoods... My primary bench is about 30 feet from my back porch with targets at 10 and 25 yards (primarily for pistol) plus 100 and 250 yards. I go back into the house to the reloading bench if I want to mix up a different load. Once happy with a load I drive several hundred yards up my road (it's a dead end road) in my JD Gator to my bench at the 400 yard range that shoots across our 5 acre pond and try the load out.
I do have to watch out for wild game. Attached is a photo of a local resident who stops down occasionally, apparently when he hears shooting in the area. In this picture he is about 30 feet from my bench under the tarp.
Attachments
I am 1+ hour from the range. Fortunately, we have an HVAC loading room, which is complete with a chargemaster, beam scale, Rock chucker, and an AMP annealer.
Once you do it a few times, set up takes a few minutes. I use if for new cartridge rough load development (ladder etc.). On seating depth testing, I have a K&M press and Wilson seating dies I use at the bench. FYI, I took my AND/V3 to the range once.. I don't recommend it.
Once you do it a few times, set up takes a few minutes. I use if for new cartridge rough load development (ladder etc.). On seating depth testing, I have a K&M press and Wilson seating dies I use at the bench. FYI, I took my AND/V3 to the range once.. I don't recommend it.
Verify CBTO on every round after seating operation.
How does this account for the pressure and subsequently velocity increase as cartridge length changes?
Let me clarify; say you've found your accuracy node at a given velocity. When doing a seating test you are just trying to fine tune groups at that given velocity node. As you shorten or lengthen the cartridge, the velocity will change potentially throwing you outside your velocity node.
So does it just become a circular chase where as you change length you fall out of the velocity node so back to square 1?
Lenny Foffa
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I do not , but every year at the Bench rest seminar it is discussed! Many of the match winners no longer do it ! I prefer to make 2 groups of 3 to have 6 rounds of a specific powder weight ,then 6 more rounds 3 tenths more then 6 more rounds 3tenths more ! Total of 18 rounds in matched cases ! That's enough for one range session with that Rifle. Take notes And save targets ! Then back in two days to continue testing powder weights ! Then start Coal And OGIVE testing the very same way! I. May need 7 or 8 range sessions until I am satisfied with a group size that is accurate enough for Hunting! Then practice every week with that particular load ! I think I am more focused on making the loads at my bench at home Then I would be the range !! Just me !!
Chrono data verifies effect of any pressure changes, but does not guarantee precision. As you know, not sure if you are just trolling or not, there is not a magic formula you do this, you do that, you get what you want. Too many variables, but the case being a pressure vessel variance in initial volume, other things being equal, pressure changes. To what effect to precision is an empirical approach to most.
You probably know the answer, just trying to figure out if others do.
Carry on.
QuietTexan
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Not if your nodes are wide enough, your testing fine enough to find the edges of them, and you take enough shots to have inferential results.
Doing the big coarse seating test jumps can be enough to significantly change case capacity, but IMO a 0.002"-0.020" fine tuning range shouldn't push you out of the velocity node. If it does you're in a marginal node and probably should use a different powder.
I was in a rush to finalize a load last summer - 100*f+ temps and needed to get it done in very few range trips (I only had three days on the calendar to work with), so I came up with a grid method to give me some hard data to back up where I landed in my initial seating depth and pressure ladder. Shot 0.003" longer and shorter, and .2gn higher and lower powder charge, said all of them should shoot pretty much the same if I'm in a good, resilient place. They all shot about the same, and I took the final "middle" load to 1200 yards the next day. My 10-shot SD/ES was something like 11/35, not something to make the math wizards happy, but it printed well on target.
Something like this:
If one row or corner had sucked really bad I could have moved left/right or up/down in the grid and at least not been totally guessing about what the results would be since I had at least a group of 5 at each setting combination, on top of the initial pressure/seating depth work ups.
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