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Discussion Starter #1
LOWER:
PSA lower with PSA LPK, ALG Defense QMS trigger w/JP lo-power springs
Magpul STR stock w/standard buffer, PRI 10rd mags

UPPER:
Ares Armor upper receiver, ARP 20” target crown barrel
Syrac Ind adjustable gas block, PSA full-auto carrier with ARP Superbolt

BRASS:
All brass was pulled non-fired (factory primers) Federal from RMR.
Sized through a Hornady New Dimension full-length die with the expander ball removed
Charges poured with a RCBS Chargemaster, with each first load in a series double-checked against my Dillon Eliminator.

BULLETS:
110gr Sierra ProHunter seconds… hand sorted purchase from Owenslee
110gr Barnes TSX
90gr Gold Dot pulls from RMR

POWDER:
AA1200R, H335, Benchmark, RL-10X

OK… my groups suck. I know the gun is capable of way more than this. All shots were off a front rest / rear sandbag and a Bushnell AR Optics 4.5-18… not the greatest scope, but overkill for 100yd test-firing. My stuff is all over the place. There are a couple of combos that work out better than others, but “general suckage” abounds. I have some chrono readings I’ll post when I get home which may help the investigation.

For the next round of testing, I’m gonna buy a couple boxes of factory something and get a good baseline. Also… way more brass prep. First off, use the expander ball and step up to magnum primers. I would have used the expander ball on my initial loads, but didn’t know you would take out the decapping pin separate from the ball on the Hornady dies. I’ve got a Wilson Case guage, so I can set the die properly… and calipers and all the other stuff to make good brass. I’m going to hand-weigh each charge on the Dillon Eliminator and do all my work on a Forster Coax vice my Dillon 550.

Any other advice… anything you guys see room for improvement?
 

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If a LGS has them, the Hornady 110 bthp should be very accurate out of your barrel. I just ordered a case for $167.00 from LAX, per box they are $16.75. 1/2" groups at 100yds for me out of my 18" ARP midweight. I'll let the experts chime in on the reloading.
 

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i will say too many types of load. work up one at a time. magnum primers a must. what was your COAL (made a big dif for me). get your headspace correct as u mentioned. can't comment on your powder choices my best luck is with h322, sub moa, and aa2200 about moa
 

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I'm not sure about the Hornady die, but a Lee die without the expander will size the neck down way too small. That would give you extremely tight neck tension and poor results.
 

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Sam: Don't despair, you are on the right track. You definitely have a good barrel. The first step is to try a variety of bullets. Of the 3 tried so far, your rifle seems to like the 110 grain Sierra Prohunters the best. By now you should have some empty brass fired in your rifle. Carefully clean and size those, setting the shoulder back about .004 to .005" from the fired dimension.

Next step is to try several powders with the favored bullet. The two you tried, 1200R and H335, are probably not the best choices, IMO. Instead, get a pound each of H322 and A2200, along with some CCI 450 or Remington 7-1/2 primers (hot mix, hard cup). Try a ladder with each of those powders under the Prohunters, starting at 28 grains and working up slowly to no more than 29.5 grains. Load to longest OAL your mags will allow without any rubbing of the tips, usually about 2.290 to 2.295". Stop when accuracy tightens or swipes on case heads start to show up, whichever comes first. Use your chronograph to monitor velocity readings, esp the standard deviation of 10-round shot strings.

If all that doesn't pan out for you, substitute some other bullets from the chart posted here, e.g., Nosler 115 gr CCs, and repeat the ladders with H322 and A2200. Patience, persistence and attention to detail will eventually pay off. From my POV, 10 rounds into less than an inch CTC at 100 yard/meters is the gold standard. Standard deviations in the 10 to 15 fps range are quite possible with this cartridge. - CW
 

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You say you removed the expander ball for sizing. Did you reinstall and push it back through the neck?
Cajun: Please restate your question. The Redding type S dies can be used with or without an expander ball. I recently converted to the latter option. The .300" bushing squeezes the neck down as the case enters the die, no need to expand it back up so long as neck thickness is relatively uniform. I initially thought the neck tension would be too tight without an expander, but that turned out to be not the case with my Hornady brass. - CW
 

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For the sake of ruling it out... your scope mount/rings didn't loosen up on you, and the mount is on the receiver, not the fore end? And... you're holding consistently level, not canting the rifle?
 

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I think the problem is you haven't tried different charge weights with the same bullet and the same powder. You have 3 different bullets with 3 different powders but only one charge weight with each. You should have 1 bullet with 1 powder with at least 3 or 4 different charge weights. You need to see which charge weight stabilizes the bullet best for that bullet/powder combination.
 

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Cajun: Please restate your question. The Redding type S dies can be used with or without an expander ball. I recently converted to the latter option. The .300" bushing squeezes the neck down as the case enters the die, no need to expand it back up so long as neck thickness is relatively uniform. I initially thought the neck tension would be too tight without an expander, but that turned out to be not the case with my Hornady brass. - CW
The OP isn't using a Redding bushing die, so the question Cajun and I asked makes sense. I know from personal experience the Lee 6.8 dies require the expander or the case neck is sized much, much to small. I loaded a few to see and the neck was so tight that the bullet caused the neck to bulge as it was seated. If the Hornady is similar that would cause a lot of problems.
 

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I tend to work with one bullet at a time, 2-3 diff powders. IMO, pulled bullets never give great accuracy. 2nds, just depends. So if you are trying out a new rifle, feed it quality products so you eliminate some variables. I also like to get a benchmark with decent factory ammo. I see some decent groups, so I doubt the rifle is suspect.
 

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I tend to work with one bullet at a time, 2-3 diff powders. IMO, pulled bullets never give great accuracy. 2nds, just depends. So if you are trying out a new rifle, feed it quality products so you eliminate some variables. I also like to get a benchmark with decent factory ammo. I see some decent groups, so I doubt the rifle is suspect.
i agree 100%. had some sierra match seconds, they did not shoot as well as the regular match bullets, nor have any pulled bullets i have had save those for plinking with the kids
 

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I concur with load adjustments. What I saw was several almost identical groups around 2" . It may take a full gr to close the groups but I had a rifle once that would go from 5 touching to 4 " in 1.0 gr in an 06'. Probably you're looking at a tune of the load more like .2-.4 gr up or down .
 

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+3
If you pulled the expander ball your inside neck dimension and neck tension are not right !

Change 1 thing at a time and keep a log.

I would try to work up an accurate load with first quality bullets to start with.
Then you can see if the seconds shoot as well.
 

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With regular dies some people will remove the expander,size the brass then reinstall the expander and push it into the case instead of pulling through. Supposedly helps runout. Since this was pulled,primemd brass I'm assuming the op removed the expander because he didn't want to deprime.
 

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Discussion Starter #19
You guys are confirming my suspicions.

Scope is tight on an SWFA mount and on the receiver.

I’m using Hornady dies… I pulled the decapping pin/expander because I didn’t want to punch out the primers. I figured that since they were pulls, the necks wouldn’t need to be expanded and I could get away with just a full-length resize. I’m seeing in retrospect that this creates uneven neck tension. Combine that with some out-of-spec pulled bullets and factory primers that might not work so well with the powder I was using… it’s a good thing I’ve got an awesome barrel or who knows if I would even have hit paper.

EROD, if you look next to each group, I’ve written the charge weight for that group and the rough caliper measurement… each group on each paper increases in .5gr increments starting with the top-left group. For example, the best group I shot was 1.18” with the 110ProHunters and 29.5gr of A1200R.

OK, so for my next batch, I’ll keep it simpler. I’ll put aside the Gold Dots for now and stick with both the 110gr bullets, and two powders… A1200R and H335. I’ve been looking for H322 and A2200, but no luck locally. Magnum primers are no problem. I’ll work up loads at .2gr increments in 5shot groups and make sure I prep the shiz out of my brass.

I hit up an LGS at lunch and bought a box of the Hornady Match BTHP and a box of S&B 110gr FMJ’s… will be able to get a couple baseline groups with factory ammo and see if it’s just me that sucks.
 

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I tend to work with one bullet at a time, 2-3 diff powders. IMO, pulled bullets never give great accuracy. 2nds, just depends. So if you are trying out a new rifle, feed it quality products so you eliminate some variables. I also like to get a benchmark with decent factory ammo. I see some decent groups, so I doubt the rifle is suspect.
Whether or not a pulled bullet is accurate or not depends on a lot of factors, but you cannot say they 'never give good accuracy' because that is simply not true. The 90 gr. Gold Dot pulls that were available awhile back in large quantities are very accurate. I could shoot them into raggedy bug holes at 100 yds from both my 6.8 and my .277 WLV.

As far as the 6.8 goes, I don't know how you can get a benchmark from a factory load that is considerably under powered compared to good handloads, due to SAAMI limitations.

There are proven accuracy loads that work in 95% of the 6.8 rifles out there. One such is 28.5 (+- .2) 2200, CCI-41, Hornady 110 HPBT w/c, seated to cannelure.
 
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