Originally posted by GSPHunter
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Safety ladders with CFE223 and 123gr. SST's
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quis posuit in mea ocreis bologna!
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For really helping sort out accuracy and the right OCW load (which for the unfamiliar is a "modified" ladder test developed by Dan Newberry - click here for an overview http://optimalchargeweight.embarqspace.com/ and here http://optimalchargeweight.embarqspa...ons/4529817134 for more details of the procedure), I have found the software from Jeffrey Block's OnTarget Data systems http://ontargetshooting.com/tds/ to be very helpful, especially if you want accurate group measurements and comparisons of your different groups' point of impact relative to point of aim. Some of us (try to) measure things beyond the practical level of significant digits, but for those who want to measure and compare things as accurately as our budgets and equipment allow, I have found this to be a cost effective software for helping analyze OCW and group size data.My "6.5" = 24" AA Overwatch upper 1/9 twist, NC based US Tactical lower, standard A4 6 position stock, AR Gold Trigger, JPS SCS buffer, Vortex 6-24 x 50 FFP PST with EBR-2C MOA reticle
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Originally posted by Jakal View PostThis thread hit at the right time for me. They way I work up a load is to run 1 charge of each weight just to look at the primers and see were the edge is. So from a 30 to 32 ladder, I will load up 30 30.5 31 31.5 and 32. I shoot these to get a baseline. I then go back and drop off maybe the 30 and 30.5 but run 5 rounds each of the 31 31.3 31.6 and 31.9. I will take the low and high accuracy nodes and go to .2 of a grain both above and below those charges. So if the 31.3 and 31.9 are the low and high, the next charge ladder will be 31.1 31.3 31.5, & 31.7 31.9 32.1. Run all of these over the CED chronograph while watching for primer issues.
By this time I have a real good idea of where the load will be. I will take the fastest and accurate load. Even if that means I settle on the low accuracy node. I'll sacrifice speed for accuracy.
The primers are not a reliable method for gauging excessive pressures either.NRA Basic, Pistol, Rifle, Shotgun, RSO
CCW, CQM, DM, Long Range Rifle Instructor
6.5 Grendel Reloading Handbooks & chamber brushes can be found here:
www.AR15buildbox.com
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Agree with the 1% steps, have been doing that for years. Lot of things effect chamber pressure and Primers though often talked about can be an indication of pressure but they are not a reliable one. By the time "Classic" primer indications appear a load will be sometimes be over pressure, sometimes way over pressure. I will look at the primer but look at the case more, is it getting any shiny spots on the case head, measure the case for expansion at the webb. Stress fractures are real and not just on jet aircraft (remember the Concord) where we hear most about it.
The only firearms I look very closely at the primer for pressure indications is the TC Contenders, there when you are getting to max load for your Contender. On the Contenders with the centerfire and rimfire fireing pins and holes you will see the primer begin to faintly flow into the rimfire hole when you are at the pressure to stop at and back off a tenth or two.
When shooting ladder tests I will use different colored sharpies to mark the bullets out toward the tip, sharpies have a little corrosive chemicals so don't mark far enough up the bullet to contact the lands. The colored bullet will transfer the color mark to the target, making it easier to see which bullet made which hole. This works on white paper, not so much so on other colors or card board.
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Originally posted by rickOshay View PostHeywood - I may have missed it skimming, but what is the max COAL in your chamber for the 123 SST.quis posuit in mea ocreis bologna!
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Originally posted by Savage Shooter View PostFor really helping sort out accuracy and the right OCW load (which for the unfamiliar is a "modified" ladder test developed by Dan Newberry - click here for an overview http://optimalchargeweight.embarqspace.com/ and here http://optimalchargeweight.embarqspa...ons/4529817134 for more details of the procedure), I have found the software from Jeffrey Block's OnTarget Data systems http://ontargetshooting.com/tds/ to be very helpful, especially if you want accurate group measurements and comparisons of your different groups' point of impact relative to point of aim. Some of us (try to) measure things beyond the practical level of significant digits, but for those who want to measure and compare things as accurately as our budgets and equipment allow, I have found this to be a cost effective software for helping analyze OCW and group size data.quis posuit in mea ocreis bologna!
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Originally posted by LRRPF52 View PostFor those that are wondering what kind of real world longevity you might get, I have been loading 31.2gr of CFE under the 123gr A-MAX since late 2012, when I did my first pressure ladder with CFE/123gr A-MAX.
The pressures are very low with 31.2gr, but still give me 2500fps. 31.1gr gives me 2489fps, and 31.4gr gives me 2520fps, again from a 16" little carbine.
This discussion is another great example of how small increments equal large jumps in pressure with a case that holds 34-35gr of water.
.3gr of charge weight increase increases the pressure substantially. I would consider loading in .2gr increments as you pass 31.0gr just to help dial-in an accuracy node.quis posuit in mea ocreis bologna!
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To be totally honest, we could spend all day following benchrest techniques for OCW, or just pick a load that is safe, mass-produce it, and go out and practice with that load.
The by far biggest variable in all of this is the wobbly, beating heart, expanding-contracting lungs, attention-deficit disorder shooter. Load up a decent charge weight, get out and start blasting. It takes a lot of work to be able to consistently hold even 1 MOA for me. Sure, I can cherry-pick my groups and only show the best ones, then claim what a great shooter I am, but the reality is that I get rusty when I don't practice, so what's the shortest route for me to get out and shoot in volume with clear performance goals?
Crank out a box or two of hand loads using consistent, quality components, or grab a case of factory ammo and go to the range.NRA Basic, Pistol, Rifle, Shotgun, RSO
CCW, CQM, DM, Long Range Rifle Instructor
6.5 Grendel Reloading Handbooks & chamber brushes can be found here:
www.AR15buildbox.com
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Originally posted by LRRPF52 View PostTo be totally honest, we could spend all day following benchrest techniques for OCW, or just pick a load that is safe, mass-produce it, and go out and practice with that load.
The by far biggest variable in all of this is the wobbly, beating heart, expanding-contracting lungs, attention-deficit disorder shooter. Load up a decent charge weight, get out and start blasting. It takes a lot of work to be able to consistently hold even 1 MOA for me. Sure, I can cherry-pick my groups and only show the best ones, then claim what a great shooter I am, but the reality is that I get rusty when I don't practice, so what's the shortest route for me to get out and shoot in volume with clear performance goals?
Crank out a box or two of hand loads using consistent, quality components, or grab a case of factory ammo and go to the range.
Besides, I run through thousands of rounds of 5.56 and 9mm per year so I like to take a different approach with my Grendel.quis posuit in mea ocreis bologna!
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With that 31.2gr CFE load that I really didn't even do any OCD/OCW development for, a friend of mine who was shooting the Grendel for the first time cleaned a Know Your Limts plate rack with it at 500yds. The little carbine is a consistent 1 MOA AR15, no matter what I really do to it, so I can't complain.
We'll be shooting nothing but field positions in my course next weekend. When you take those positions, then use them in natural terrain, with more steel than you can find in the target area, it becomes a lot of fun.NRA Basic, Pistol, Rifle, Shotgun, RSO
CCW, CQM, DM, Long Range Rifle Instructor
6.5 Grendel Reloading Handbooks & chamber brushes can be found here:
www.AR15buildbox.com
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I am very bummed that I couldn't make the time to go. I was hoping sometime to be able to take some lessons from someone who knows what this cartridge can do and has real world experience. It's kinda ridiculous really. I have over 240 hrs vacation saved up and I still can't find time for the important things in life.quis posuit in mea ocreis bologna!
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Sry to necromancer this thread, but is anyone running these loads from an AR? I need COAL for mag length seat depth restrictions. Should I just load to 2.260? I am about to start a run of CFE223 under some 123gr SST's myself. Gonna be slingin them from a Shilen 24" barrel.
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I settled on 31.6 grains of CFE223 @ 2.255. Find out how far you can load before jamming the lands. Length should be determined from the chamber, if a long chamber, you may have to stick with mag length.""Come taste my Shillelagh you goat-eatin bastard!""
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