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243 AI searching for accuracy

DLCrocket

Silver $$ Contributor
I have a 243 AI with a 1 in 7 match barrel from Criterion. Without going into all the details of how I uniform the brass etc., I've been trying to dial in Hornady 108 ELDs using H4350. Ive exhausted just about every combination of powder charge and seating depth possible. I had some loads with pretty type groups at 100 yrds but high SD and ES. The loads that had low SD and ES (not many) had bigger groups. When I tried the load with the best group and ES/SD at 200 yrds the groups fell into a 2" x 2" square. I want to get to a 500 yrd range so I want tighter groups at 200. Bottom line, trying to decide whether to try different bullets or different powder. With a pound going for $60 I'm running out of fun money so can't afford too many more combinations. Any suggestions are welcome!
 
I've often found a lot of times that low es/sd doesn't always translate into smaller groups or even the best shooting loads. I believe what the target tells me.

If I had a load that shot better downrange with a higher es/sd than a load with a lower es/sd, I would always go with the one that shot better despite what numbers the crono says.

A lot of my loads have an ES of 30-75fps and whatever SDs that translates to on any given day in a variety of my rifles. They still always seem to shoot an easy 1/2 MOA out to 500, and usually hold 3/4 MOA out to 1K for 3-5 shot groups.
 
Forget about looking at ES and do a proper load workup, I shoot with allot of 243AIs and Im yet to see one not shoot. H4350 is a good powder for 243AI and 108 ELDS are decent if your rifle is put together properly it shouldn't be hard to find a load.

Whats the load your trying now?
 
1) 1:7 in my opinion is a bit fast for a 243 AI when likely an 8 twist is more optimal.
(gotta tailor everything around the bullet, and what it can withstand...this includes the speed)
---MIGHT work if you are using a HIGH QUALITY - cut rifled barrel ---- not a buttoned barrel
2) with that fast of twist, coupled with the velocity you are capable of .......
Ditch Hornady anything
---might be fine for a 6BR, but not for a 243 or faster, Sorry man

Sorry to be the bearer of bad news but.......
.......too many people are attracted to the Hornady ELD-M for their cost
They are nothing more than an updated A-Max
There is a very good reason they cost much less per 100, you get what you pay for
They save money by using less copper, which is too expensive for Hornady to spare.
I think they horde it in the back room just so they can make more bullets.

Hornady don't survive high velocities coupled high rpm, too much frictional heat generated there.
That when gyroscopically spun up fast, separates the thin jackets from their core..
Think .023" thick vs .030" (within the realm of bullets and heat, thats a big difference )
----------------------------------------
Advice : You want accuracy? - Try some Sierra 107's or Lapua 105's or 115 DTAC
----------------------------------------
Avoid even Bergers for the time being until you test the other 3, even bergers dont hold up well to
Fast and High Rpm, and if you do opt to try some Bergers, make certain they are
{TARGET bullets, NOT Hunting}
I comtacted Berger once, inquiring (basically to let them know their 6mm bullets werent living up to expectations)
Their response was : Well you're pushing them past their designed limitations.
That is a PC way of saying "you can't drive them very fast"
Ok then Berger, I Guess Sierra gets my money then, you're over priced anyhow.
Too bad Berger is unable to design durability at high velocity in with accuracy for the money they charge.
----------------------------------------
Pic 1. (trying to use Hornady's - Notice the comet tail on the outer perimeter of the bullet hole
This is the jacket not being thick enough to be a thick enough heat sink to handle the heat and
angular momentum produced from the velocity generated from somthing like a fast .243
(You COULD, tune your load down to 3000 fps, but then why have a 243 AI?)
So you're gonna have a cartridge that is capable of 3300 fps, but then tune down to 3000 fps just to use Hornady's? Doesn't make sense right?

Pic 2. Sierra's - Notice complete jacket integrity kept from the virtue of using thicker jackets and tougher copper
Sierra = Gilding metal vs J4 jackets - Sierra = the tightness of what you seek. ;)
These were all tested with the same load, showing a vast difference between the three
IE: I mean, why waste your time if accuracy is what you're after rather than explosive results?
4831 and Reloder 22 would be 2 other powders to try, I've had very good results with those powders
Here is some load data which may help with load info
If you try the 115 DTAC, Def try some H1000 with those, it's very consistent.
 

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Why avoid Bergers and stick with Sierra for the time being until you get the bugs worked out???
Here's why, even with their Tote's Awesome 109 "Hybrid"
(That word Hybrid is a real "fisherman catcher" of an advertising term... rather than a fish catcher)
Now this example of the Berger 109 did not happen often, most the time they shot tight
IF.... I tuned down to approx 3200 fps.
but the fact that it happened even ONCE, is too much
 

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I have a 243 AI with a 1 in 7 match barrel from Criterion. Without going into all the details of how I uniform the brass etc., I've been trying to dial in Hornady 108 ELDs using H4350. Ive exhausted just about every combination of powder charge and seating depth possible. I had some loads with pretty type groups at 100 yrds but high SD and ES. The loads that had low SD and ES (not many) had bigger groups. When I tried the load with the best group and ES/SD at 200 yrds the groups fell into a 2" x 2" square. I want to get to a 500 yrd range so I want tighter groups at 200. Bottom line, trying to decide whether to try different bullets or different powder. With a pound going for $60 I'm running out of fun money so can't afford too many more combinations. Any suggestions are welcome!
Sometimes a barrel just does not like a bullet for whatever reason. Period. Waisting components trying to make it work, most times, does not work. Pick a known tough target bullet and try it. As in the Sierra 107. If the Sierra works, now you know the gun will shoot. Now find a comparable brand of bullet to the Hornady that the rifle likes and carry on. Maybe a Nosler, Sierra, Berger, ....etc. Look at the target and not the chrono for your results. Most times small sd and small groups do not coincide. Good luck and keep us posted.
Paul
 
Sometimes a barrel just does not like a bullet for whatever reason. Period. Waisting components trying to make it work, most times, does not work. Pick a known tough target bullet and try it. As in the Sierra 107. If the Sierra works, now you know the gun will shoot. Now find a comparable brand of bullet to the Hornady that the rifle likes and carry on. Maybe a Nosler, Sierra, Berger, ....etc. Look at the target and not the chrono for your results. Most times small sd and small groups do not coincide. Good luck and keep us posted.
Paul
Lots of truth here. Most of the time when I'm working up loads the better group will have the highest E S and S D. Hard to figure out a load if you allow those numbers to dictate the outcome at 100 yds.
 
Thank you guys, I appreciate the advice, especially about not worrying over the chronograph numbers. I was trusting sources that said high numbers will make long distance groups erratic. I'm giving up on the Hornady ELDs and H4350. I also burnrd up a box of Berger 115 ELDS and just couldn't get them to group. Going to try Sierra MK 110 hpbt and RE16. If I can shrink that 2x2" @ 200yrds in half I'll try 500yrds.
 
If you want a load that will work at 500, I would do ladders at 500. I have burned out a few 243 AI's and they all liked 105 Bergers and H4831sc. As boltfluter said sometimes a barrel doesn't like a bullet.
 
Forget about looking at ES and do a proper load workup, I shoot with allot of 243AIs and Im yet to see one not shoot. H4350 is a good powder for 243AI and 108 ELDS are decent if your rifle is put together properly it shouldn't be hard to find a load.

Whats the load your trying now?
Was using Hornady 108 ELDs with H4350. Tried many combos of grains and seating depth till I found one that was under .5 moa at 100yrds. Wasn't happy with it at 200. Going to try Sierra MK 110 HPBT with RE 16.
 
1) 1:7 in my opinion is a bit fast for a 243 AI when likely an 8 twist is more optimal.
(gotta tailor everything around the bullet, and what it can withstand...this includes the speed)
---MIGHT work if you are using a HIGH QUALITY - cut rifled barrel ---- not a buttoned barrel
2) with that fast of twist, coupled with the velocity you are capable of .......
Ditch Hornady anything
---might be fine for a 6BR, but not for a 243 or faster, Sorry man

Sorry to be the bearer of bad news but.......
.......too many people are attracted to the Hornady ELD-M for their cost
They are nothing more than an updated A-Max
There is a very good reason they cost much less per 100, you get what you pay for
They save money by using less copper, which is too expensive for Hornady to spare.
I think they horde it in the back room just so they can make more bullets.

Hornady don't survive high velocities coupled high rpm, too much frictional heat generated there.
That when gyroscopically spun up fast, separates the thin jackets from their core..
Think .023" thick vs .030" (within the realm of bullets and heat, thats a big difference )
----------------------------------------
Advice : You want accuracy? - Try some Sierra 107's or Lapua 105's or 115 DTAC
----------------------------------------
Avoid even Bergers for the time being until you test the other 3, even bergers dont hold up well to
Fast and High Rpm, and if you do opt to try some Bergers, make certain they are
{TARGET bullets, NOT Hunting}
I comtacted Berger once, inquiring (basically to let them know their 6mm bullets werent living up to expectations)
Their response was : Well you're pushing them past their designed limitations.
That is a PC way of saying "you can't drive them very fast"
Ok then Berger, I Guess Sierra gets my money then, you're over priced anyhow.
Too bad Berger is unable to design durability at high velocity in with accuracy for the money they charge.
----------------------------------------
Pic 1. (trying to use Hornady's - Notice the comet tail on the outer perimeter of the bullet hole
This is the jacket not being thick enough to be a thick enough heat sink to handle the heat and
angular momentum produced from the velocity generated from somthing like a fast .243
(You COULD, tune your load down to 3000 fps, but then why have a 243 AI?)
So you're gonna have a cartridge that is capable of 3300 fps, but then tune down to 3000 fps just to use Hornady's? Doesn't make sense right?

Pic 2. Sierra's - Notice complete jacket integrity kept from the virtue of using thicker jackets and tougher copper
Sierra = Gilding metal vs J4 jackets - Sierra = the tightness of what you seek. ;)
These were all tested with the same load, showing a vast difference between the three
IE: I mean, why waste your time if accuracy is what you're after rather than explosive results?
4831 and Reloder 22 would be 2 other powders to try, I've had very good results with those powders
Here is some load data which may help with load info
If you try the 115 DTAC, Def try some H1000 with those, it's very consistent.
"Loads" of good info. Thanks. Some background, years ago when I started shooting prairie dogs one of my buddies talked me in to the 243AI. Speed was definitely a consideration as it's always fun to see a prairie dog jump, but also I was told that the 40° shoulder directed the combustion more to the center of the bore resulting in longer throat life. Later I decided that speed wasn't as important to me as throat life and cost of powder. Also, much of the load data for the standard 243 stop with maximum loads resulting in under 3000 fps, so to be honest I haven't done much testing with the extra 7% volume of the AI cartridge, and I don't have much information about how higher velocities affect accuracy. So I'm definitely not taking full advantage of the cartridges abilities. Because of age and the passing away of some of my shooting Buddies I'm pretty much relegated to targets these days.
 
Why avoid Bergers and stick with Sierra for the time being until you get the bugs worked out???
Here's why, even with their Tote's Awesome 109 "Hybrid"
(That word Hybrid is a real "fisherman catcher" of an advertising term... rather than a fish catcher)
Now this example of the Berger 109 did not happen often, most the time they shot tight
IF.... I tuned down to approx 3200 fps.
but the fact that it happened even ONCE, is too much
I struggled with Berger 115 ELDs. Gave up on them after reading "VLD - Making them shoot" on their website. It says to try seating from 0.010" into the lands to .120" off the lands. Struck me as crazy.
 
I struggled with Berger 115 ELDs. Gave up on them after reading "VLD - Making them shoot" on their website. It says to try seating from 0.010" into the lands to .120" off the lands. Struck me as crazy.
I was able to get the Berger 115 Target bullets to shoot (8 twist)
The 115 "HUNTING" bullet is the one I had most problems with -thin jackets for hunting
Thats it THE particular bullet I complained to Berger about
I really was hoping they would see the problem and simply use thicker jackets
I mean if people are willing to pay for it, they will sell, yet they dont see it
---------------
The Target 115 shot fine but not as well as Dtacs
Meaning you can drive Dtacs to high velocites and still get excellent accuracy
With Bergers they seem to like a more conservative velocity
And yes They like being into the lands pretty well, actually more like +.060"
I do not shoot the long 6mm VLD"s off the lands at all, their long ogive really lends itself to being stuffed into the lands
--------------
Bergers window of VLD seating depth may be a good window to work within, but slide the scale more into the lands, I do like berger did a lot of testing with seating depth going so far back off the lands and them finding several seating depth nodes within that wide window that works.
Something like there could be 3 seating depths possible to use approx. .040" apart each
Dont know if thats the same article you read or not,
Bergers 115 TARGET, can be made to shoot well if not going much over 3200 fps
Again, Copper vs Gilding metal
------------
Surprisingly, 112 Matchburners were better than Bergers as far as holding up well
Grouped respectably too, for the small sample I tested anyway. and were actually more of a consistent bullet in regards to Base to Ogive length than Bergers
 
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