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Ugly extreme spread........now what ?
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I have a .003 bushing I'm going to use going forward. I am going to polish the interior of the bushing too, so it will probably be closer to .002 by the time I get around to using it.
Just to explain my thinking for the .005 I was using. Since I'm using this gun for hunting as well as informal target fun, I wanted to be sure the bullets wouldn't move in the cases when subjected to recoil in the magazine. Just my overbuilding ways.
I hear ya...but neck tension is one place less is more
also look at a previous post I made to your issue in this thread...
Thanks for the advice and I may find myself taking you up on a PM or 2 , if I run into issues and need solid advice from someone who does the LR stuff.
As for now, I just have to put into practice the things I already want to do. It's so hot here this time of year and the humidity is brutal. I cant get much quality time in at my bench before the heat takes all the fun out of shooting . Maybe have 2 hrs in the early AM before the crosshairs start dancing and the sweat starts rolling. I still have about half my brass to fire form before I can get down to the business of nailing down a great load.
totally understand... I have lived several times in the southern US and would start shooting around 5-6 am to end by 9ish at best lol
I agree that 1-2 is a good tension for single loaded target loads. For a hunting load it needs a min of 3 better at 5. The issue sin't so much how much neck tension as consistent neck tension. In fact too low a neck tension with a robust primer can cause extreme variations in ES and you see this often in smaller cases using magnum primers. If they are all 5 then the SC/ES will be fine, if some are 2 and others are 6, wide variation in ES. For a hunting load I think you were on the right track already when you were working on loads with a 5 thou neck tension. Personally I would stick with the 5 neck tension and work on getting zero run out, even neck thickness, even tension and work on the other things that will bring down ES.
Dean 2,
I have never experienced what you are saying nor have I heard of it? Are you speaking from experience or arm chair theory?
Just curious because I run 338 Edge, 375 Chey tac and light weight 7mm 08, 6.5 etc etc and shoot PRS as well dabble often in the long range game ( point is I shoot a lot and I am around a lot of shooters) and I have never heard 1-2 thou neck tension is too light. I have heard of and witnessed just the opposite with neck tension being too much and caused high or erratic ES issues.
Yes I have seen it in real life. I do a lot of shooting, most years at least 5000 rounds of center fire, but it is almost all in aide of developing top notch loads and being a better shot for hunting. Heavy recoiling cartridges like the 7 and 300 RUM, the bullets on the rounds in the mag will push back into the case if you only have 2 thou neck tension. I have even seen this happen in 308 in a light gun. The change in COAL has a far bigger effect on accuracy than a slightly larger ES.
The big ES effect with too light a neck tension is easiest to see in really small cases like the 22 H. Shoot a regular load with a mag primer, standard primer and SP primer. You will see a huge difference in ES. If you take and lightly crimp the load with the Mag primer, the ES comes right back down. Same thing happens with larger cases, just not to the same degree and many people never test regular, mag and BR primers in the exact same load so they never see the effect clearly.
We also load all of our hunting ammo with magnum primers for that extra bit of assurance when it gets to -40. I know that lighter primers might garner slightly better groups but I will give up a little for the reliable ignition. We use CCI 250 to 65 grains and Fed 215 for anything the uses more powder than that because we have seen lots of click booms or failures to fire, even in warm weather, using CCI 250 in cases running 75-115 grains of powder.
I hunt a lot and all over the world. To me there is a real big difference between developing hunting loads and pure target loads. Hunting loads need to be 100% reliable and as impervious to recoil, transport, temperature fluctuations, rain, snow and the like as possible. I am not saying your loading techniques are not better for pure accuracy, I am just giving my experience with respect to loads that are being developed for use under the extreme conditions often encountered when hunting.
I don't usually post so many times on one threat but I think this topic is very important. I have seen more than a few failures of hand loaded ammunition in hunting scenarios, both by other hunters and from clients when I used to guide and a lot of it can be traced back to loading for maximum accuracy on targets. Cases that fail to feed smoothly or at all, cases that stick due to over pressure in heat, failures to fire in extreme cold, broken extractors or firing pins from blown primers or split cases, and bullets that fail to perform on game because they were chosen for max accuracy rather than max performance on flesh. It happens often enough that I believe it is a real problem, not bad enough to recommend factory ammo for hunting but definitely common enough to say that a lot of guys need to pay way more attention to reliability and on game performance of their hunting loads.
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Didn't read the whole thread because of lots of pages so this is maybe a repeat. Just drop down about 5% below your max charge weight and load a single shot in .2 or .3 gr. increments all the way up to max charge weight. It'll be about 15 shots or so. Shoot them over a chronograph and record your readings. Chances are, two or three will be very close together. Load about 10 shots with a powder charge smack dab in the middle of where your test showed the best ES. Test for ES and accuracy. H-4350 and RL-16 are good powders in that caliber.
Also, before I do any load workup, I do a rough seating test first.
Also, before I do any load workup, I do a rough seating test first.
My intentions are to shoot these seat depth test loads I loaded to find the sweet spot on seating depth, but the gun /load combination has shown no real preference over a pretty wide range. I have 5 shots each loaded in .01 steps from 1.99 to 2.05 lengths from back of case to ogive. After I shoot all 100 Peterson brass once and weight sort , I'm going to load 10 rounds in .1 steps from 41.6 to 42.6 to look for the sweet spot. I will load below or above those numbers if the test shows the "zone" is towards one end or the other of the string.
There should be a pretty good load worked up by the time all that is done. If I cant get ES inside 25 after that, I will crack the seal on the H4350 sitting on the bench and try it.
The main objective is to enjoy the process . I know I dont NEED ES numbers below 25 for my 500yd hunting round, but I like the idea of a load that can outshooting me under the most ideal conditions. Makes me shoot harder because I know a miss is all ME !
There should be a pretty good load worked up by the time all that is done. If I cant get ES inside 25 after that, I will crack the seal on the H4350 sitting on the bench and try it.
The main objective is to enjoy the process . I know I dont NEED ES numbers below 25 for my 500yd hunting round, but I like the idea of a load that can outshooting me under the most ideal conditions. Makes me shoot harder because I know a miss is all ME !
TwoMore
Well-Known Member
I believe that the primary ignition has a lot to do with the neck tension. When I first started seeing this is when I started turning necks and setting tension low with a 7 wsm and magnum primers, my pressures rose and everything went south. when I used at least .003 it calmed it right back down. may have been a scenario where the bullet was able to contact the lands before it had any energy on it. but I use at least .003 , I really noticed it in factory loads I was shooting up for the brass and they were crimped and getting very good velocity without pressure. that made me test different tensions
Joemac6324
Active Member
How old is the barrel on your rifle?Finally bought a chrono to get serious about finding a 500yd deer load for my field rifle. THIS IS ON NEW BRASS . I found a load that shoots great at 100yds considering I'm just fire forming brass and making sure the barrel is broke in right. This string is shots 67 to 77 on a new barrel. Barrel has not copper fouled since round count 20.
Load is 41.8gns of RL16 behind a Berger 130 vld with cci br large rifle primers and Peterson LRP brass (new/unfired). Barrel was cleaned before this string was fired.
2805
2795
2787
2802
2798
2776
2827
2808
2814
2862
The barrel was getting pretty warm on the last 3 shots, but I didnt let any rounds cook in the chamber more than the time it took to chamber , square up in the graph window and squeeze the shot.
Am I looking for good ES too early in the process? Would you hunt for a better load, or relax and play with seating depths till I get the rest of this brass once fired, bumped, and weight sorted ? Oh, its s 6.5 creedmoor
WiscGunner
Well-Known Member
- Joined
- Aug 2, 2016
- Messages
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I think it is important to understand a dimension (.002) used in place of a force (neck tension) takes a lot of assumptions into account. Would be great to have a pull gage to check actual neck tension. In the mean time it is important to remember the dimensional tension of say .002 undersized ID will have different neck tension for different alloys of brass, different states of annealing, different neck thicknesses, different neck length and lubrication variables.
Personally I test this in my PRS loads two ways.
1) test for ES/SD difference across different neck diameters
2) test the best performing neck size first. I test these by loading a magazine and whacking it on the corner of my table(covered in cork) a few times with authority.
Then I measure my BTO to make sure the 10 rounds didn't shorten. If not, this size of neck ID is providing sufficient neck tension/bullet retention. If the bullets moved, I go to the next tightest setting.
This is done with fully prepped and loaded ammo. Any change later such as neck turning or annealing will loosen this retention. Work hardening the brass through a few firings will increase the neck's bullet retention until the brass is too hard to be sized properly. Annealing every time of course will give you the most consistent bullet retention with regards to the particular lot of brass hardness.
Personally I test this in my PRS loads two ways.
1) test for ES/SD difference across different neck diameters
2) test the best performing neck size first. I test these by loading a magazine and whacking it on the corner of my table(covered in cork) a few times with authority.
Then I measure my BTO to make sure the 10 rounds didn't shorten. If not, this size of neck ID is providing sufficient neck tension/bullet retention. If the bullets moved, I go to the next tightest setting.
This is done with fully prepped and loaded ammo. Any change later such as neck turning or annealing will loosen this retention. Work hardening the brass through a few firings will increase the neck's bullet retention until the brass is too hard to be sized properly. Annealing every time of course will give you the most consistent bullet retention with regards to the particular lot of brass hardness.
Its fresh. 77 shots so far.
