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Discussion Starter #1 (Edited)
Second range session Monday... w/pics and another question

Thanks for the advice on my problems with my first range session. You guys helped me identify some problems and I've made corrective actions. The good news was that the experience wasn’t a total waste, and I think I’m gonna have a lot of success with the modifications to my process.

For the next session, I’ve done some extra tumbling (because shiny brass shoots better), am using the expander ball in my die full-length die, and have chamfered my case mouths. I’m also hand-weighing all my loads on my Dillon Eliminator scale. Unfortunately, I don’t have a tool to measure my chamber, so can’t set the shoulder back properly, but I am properly using my Hornady die. I’m going to continue to use my factory-primed Federal brass from RMR until I’ve shot them all (1000 cases)… at least that way, I can be consistent with the first 1000rds. It’s gonna take me a couple years to shoot that much anyways, so no need to hurry.

I’m also going to shoot from a bipod to eliminate any chance of canting, and am going to give myself a whole morning so I’m not rushing and shooting from a really hot barrel.

Oh yeah… and I switched scopes. I think the 4.5-18x Bushnell AR Optics might have been hurting me. The cross-hairs are a little thick and the eye-relief at 18x was frustrating. I’ve replaced it with a 3.5-10x50 Nitrex that I bought based on recommendations here on this forum… it’s visibly brighter, the crosshairs are much thinner, and the eye-relief is very forgiving.

I’ve been unable to get any 332 or 2200, but have plenty of H335 and RL10x, so am loading up strings using those 2 powders with 110gr ProHunters and 110gr Barnes TSX. I’ll leave the 1200r and Benchmark for another day.

5rds ea at .2gr increments:
110gr SPH, RL10x 29.0gr - 29.8gr
110gr SPH, H335 29.5gr - 30.3gr

110gr B-TSX, RL10x 28.5gr - 29.3gr
110gr B-TSX, H335 28.7gr – 29.5gr

I’ll be using the chrony and recording every shot, plus placing spent cases back in order (in the box) and keeping track of pressure signs.

While we’re on the subject, and since I’ve already got the whole morning approved from the boss… I also have a bunch of 90gr Gold-Dots and plenty of A1200r, Benchmark, ARComp, and IMR3031… if I was going to load up anything else to test with my primed Federal brass, what would it be?

Totally open to other “improve my shooting” suggestions… will post glamour shots of ammo production when I get home from work!
 

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Just a suggestion but you may find that AR-COMP will be over gassed if you are not running an adjustable gas block. I have used it with 130SPH, 120SST and 115HPBT bullets and it is very consistent with very low extreme spreads but gives a lot of port pressure. I still plan to try it with some lighter wieght bullets just to see if it provides good accuracy and velocity with the 95-100 grain weights.
 

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You don't need a special tool to measure your bump. One easy way I do it is the 9mm case method.



Measure what you have with a fired case and adjust the die for a .004 bump. Start with the die backed out or you will probably push the first one to short.
 

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Discussion Starter #4
You don't need a special tool to measure your bump. One easy way I do it is the 9mm case method.
Measure what you have with a fired case and adjust the die for a .004 bump. Start with the die backed out or you will probably push the first one to short.
I've never seen that method... just measure the distance of an unfired case vs. a fired case? Can you point me to a Youtube video?
 

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Drop a 9mm case over the neck of a fired 6.8 and measure. If it comes out at 1.855" (made up number), you want your sized case to measure 1.851-1.853". Just twist the seating die down incrementally and measure the case each time until you get the right amount of bump.
 

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5rds ea at .2gr increments:
110gr SPH, RL10x 29.0gr - 29.8gr
You might find that a little too hot. I'd drop your starting load at least a grain.
 

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Coondog that's awesome I haven't seen that before but I get it . Very nice piece of knowledge,thanks for that.
 

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The 9mm case method works pretty well.
However do not switch cases, use the same 9mm case every time.
 

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Discussion Starter #9 (Edited)
Tried the 9mm case method... got very consistent results... fired cases were about .01 longer than both my raw unfired cases and my unfired cases that have been through the Hornady die. So I don't think I'm NOT pushing the shoulder back at all on the unfired cases when I initially size them... will need to re-adjust the die when I make my first batch of ammo from fired cases.

ALSO... GUNSHOW WIN!!! Scored a pound of H322/2200... and a 1000ct of CCI450's. Looks like I'm all set for the short term.

So... I've already got a few test batches made up with H335/RL10x and 110 SPH's/TSX's.

I'd like to make a similar batch using those 2 bullets with the new powders. I'm going to prep/load the new powders in exactly the same fashion as the current batches... and chrony everything. I should have a ton of data to share when done.

My question... to get the most benefit of the range session, and assuming I only want to shoot 25rds of each new powder/bullet combo... what should I do? 3shot groups at each powder charge over a wider charge range, or just stick with 5rds at each charge weight and try to zero in on what everybody considers the "ideal" charge for that powder?

Also, bullet porn pics for ya!






 

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There are several ways you could do it but ultimately it's up to you.
(1) Work up your powder charges incrementally with each bullet and powder type one at a time just to find what is max for you rifle then you can back off the charge and work on the accuracy.
(2) You could work up three round batches to find your accuracy nodes for each and save some components that way if you wanted.
(3) If the range you shoot at has a 300 yard line you could effectively combine step 1 and a ladder test to maximize your time and components being used.
 

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Thanks for the advice on my problems with my first range session. You guys helped me identify some problems and I've made corrective actions. The good news was that the experience wasn’t a total waste, and I think I’m gonna have a lot of success with the modifications to my process.

For the next session, I’ve done some extra tumbling (because shiny brass shoots better), am using the expander ball in my die full-length die, and have chamfered my case mouths. I’m also hand-weighing all my loads on my Dillon Eliminator scale. Unfortunately, I don’t have a tool to measure my chamber, so can’t set the shoulder back properly, but I am properly using my Hornady die. I’m going to continue to use my factory-primed Federal brass from RMR until I’ve shot them all (1000 cases)… at least that way, I can be consistent with the first 1000rds. It’s gonna take me a couple years to shoot that much anyways, so no need to hurry.

I’m also going to shoot from a bipod to eliminate any chance of canting, and am going to give myself a whole morning so I’m not rushing and shooting from a really hot barrel.

Oh yeah… and I switched scopes. I think the 4.5-18x Bushnell AR Optics might have been hurting me. The cross-hairs are a little thick and the eye-relief at 18x was frustrating. I’ve replaced it with a 3.5-10x50 Nitrex that I bought based on recommendations here on this forum… it’s visibly brighter, the crosshairs are much thinner, and the eye-relief is very forgiving.

I’ve been unable to get any 332 or 2200, but have plenty of H335 and RL10x, so am loading up strings using those 2 powders with 110gr ProHunters and 110gr Barnes TSX. I’ll leave the 1200r and Benchmark for another day.

5rds ea at .2gr increments:
110gr SPH, RL10x 29.0gr - 29.8gr
110gr SPH, H335 29.5gr - 30.3gr

110gr B-TSX, RL10x 28.5gr - 29.3gr
110gr B-TSX, H335 28.7gr – 29.5gr

I’ll be using the chrony and recording every shot, plus placing spent cases back in order (in the box) and keeping track of pressure signs.

While we’re on the subject, and since I’ve already got the whole morning approved from the boss… I also have a bunch of 90gr Gold-Dots and plenty of A1200r, Benchmark, ARComp, and IMR3031… if I was going to load up anything else to test with my primed Federal brass, what would it be?

Totally open to other “improve my shooting” suggestions… will post glamour shots of ammo production when I get home from work!
Your loading a lot of rounds in a narrow range at the upper end of the charge weights. You may consider starting lower and loading 3 each at .3 to .5 grains spread. Or start low and work up a ladder with one charge at .5 grain intervals to find max pressure and the accuracy nodes.
 

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Question for the experts here, what does a flattened primer look like? Usually that's the first sign of excessive pressure, right? (Never actually hit that spot before finding accuracy node)
 

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Thanks, good read for beginning reloader and the kinds of pics I was looking for to show a friend who is just starting.
 

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I just did a ICW test with H335 and 110 HPBT today, started at 29.0 grains and went up in 0.2 increments, I found a good node with little vertical dispersion at 29.6gr (2.265COAL) and at 29.8 my group strung vertically then at 30.0 it strung horizontally. I had been shooting 29.0 grains on silhouettes for several months now out to 500 meters with good luck but I think this node at 29.6 might be even better. I like H335 as it's very accurate and very reliable, it's not as fast as other powders but out of my 24" barrel it works.

I also did a round Robin to try and eliminate shooter or environmental influence in my groups. Load #1/target #1/shot #1 then move right to load #2/target#2/ shot #1 and run down the line shooting shot #1 for each load on each target, then go back and shoot shot #2.

I'm interested to hear how the H335 treats you. I've been happy with it! My dad is also using H335 and 110sph at 29.0 gr with good luck.


-Alexander
 

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I've never seen that method... just measure the distance of an unfired case vs. a fired case? Can you point me to a Youtube video?
If you want to keep your measurements the same in the future, be sure to use the same 9mm case from now on so that all measurements are relative to each other. That case now is one of your reloading tools, just like your caliper.
 

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Question for the experts here, what does a flattened primer look like? Usually that's the first sign of excessive pressure, right? (Never actually hit that spot before finding accuracy node)
Not necessarily. Flat primers only indicate pressure if all the other factors are correct. If headspace is excessive, you will get flat primers long before you get to the 'too hot' point. Soft primers will also show flat before that point, and may even pierce at normal pressures.

Keep your headspace to no more than .003-004", and use CCI-41 or CCI-450 primers to eliminate those problems. An unfired primer has a nice shiny surface with the edges a soft radius as it transitions to the side of the cup. When they start to get flat, the shiny goes away and as pressure rises, they will get a satin look where the bolt face imprints on the face of the cup. As pressure increases, the radius begins to take on a sharper edge. At high pressure, the edge of the primer cup will actually extrude into the chamfer around the primer pocket in the case, making the primer look much wider than it actually is.

Never use primer condition as the only criteria for judging pressure. Measure the case head just above the extractor groove, and at the body point where the brass looks sort of frosted or lightly burnished, how tight the primer pocket is when seating a new primer, and so on. If the fired primer falls out when the case is ejected, reduce that load by at least a full grain.
 
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