New 109 ELDM vs 108 ELDM

I’ve been struggling to find a load my new 6 PRC likes with the 109’s. I have tested .010” Jam, Lands, .010”, .020”, .030” and .030” jump and have not gotten any better than MOA out to 600 yards. I am using 61grs of N570 measured to the kernel, runout is good, neck tension is good.

One thing I just noticed is the tip concentricity of the 109’s is terrible from bullet to bullet. I just compared to some 108’s and it is night and day. Anyone ever see the same thing?

Next question, would it really matter?
 
Something I haven't seen mentioned is that on the Midway factory seconds I bought, weight is super inconsistent. Probably 5-10% are under 108, 20% are between 108 and 108.8, and 5% are over 109.2 grains. Not complaining, they're seconds, but that's more variability than I ever saw with 106 or 108 Hornady, or 77 Sierra seconds I've bought over the years. I haven't shot the over/underweight ones yet, but at some point I will and report back on how they do. Buyer beware if they ever pop back up, I'll be buying firsts from here on our with these.
 
I’ve been struggling to find a load my new 6 PRC likes with the 109’s. I have tested .010” Jam, Lands, .010”, .020”, .030” and .030” jump and have not gotten any better than MOA out to 600 yards. I am using 61grs of N570 measured to the kernel, runout is good, neck tension is good.
Try a different powder, seating depth likely doesn't matter in that chamber because of it's proper geometry.

One thing I just noticed is the tip concentricity of the 109’s is terrible from bullet to bullet. I just compared to some 108’s and it is night and day. Anyone ever see the same thing?

Next question, would it really matter?
I would assume inconsistent tip concentricity could contribute to drag variability, but it would take a pretty large sample to prove it. If you were shooting sub MOA groups at 100 yards and weren't getting consistent impacts on an MOA target at long range in good conditions, that could be an issue. But it sounds to me like your barrel isn't jiving with either that bullet, or the powder. I would try swapping one of the two and see if it responds well.
 
Something I haven't seen mentioned is that on the Midway factory seconds I bought, weight is super inconsistent. Probably 5-10% are under 108, 20% are between 108 and 108.8, and 5% are over 109.2 grains. Not complaining, they're seconds, but that's more variability than I ever saw with 106 or 108 Hornady, or 77 Sierra seconds I've bought over the years. I haven't shot the over/underweight ones yet, but at some point I will and report back on how they do. Buyer beware if they ever pop back up, I'll be buying firsts from here on our with these.
I bought from GAP and it was a bag of 500, no box or paperwork... Should be firsts, but all the weights are within a .5 grains.
 
I bought from GAP and it was a bag of 500, no box or paperwork... Should be firsts, but all the weights are within a .5 grains.
Mine are a little ugly but shoot great in my 6 creeemoor. I’d try another powder then move on if it’s not meeting expectation. With the speed of the 6prc some Berger’s might be a good choice
 
I’ve been struggling to find a load my new 6 PRC likes with the 109’s. I have tested .010” Jam, Lands, .010”, .020”, .030” and .030” jump and have not gotten any better than MOA out to 600 yards. I am using 61grs of N570 measured to the kernel, runout is good, neck tension is good.

One thing I just noticed is the tip concentricity of the 109’s is terrible from bullet to bullet. I just compared to some 108’s and it is night and day. Anyone ever see the same thing?

Next question, would it really matter?
Have you tested any other bullets in the barrel?
 
108's Shot about 2" MOA during fireforming afer the neck down from 6.5. I was shooting a mild load of 4831SC and was not focused on accuracy.
That’s still not really ideal. I couldn’t even make one of my 6 PRC’s shoot 2 MOA if I tried, even with virgin brass necked down.

Maybe try some Berger’s if you have them. But from my experience, barrels/builds either shoot or they don’t.

58gr. H1000 is another good load if you have the powder. But I doubt it’ll cut your groups in half honestly.

What’s the barrel and build info?
 
That’s still not really ideal. I couldn’t even make one of my 6 PRC’s shoot 2 MOA if I tried, even with virgin brass necked down.

Maybe try some Berger’s if you have them. But from my experience, barrels/builds either shoot or they don’t.

58gr. H1000 is another good load if you have the powder. But I doubt it’ll cut your groups in half honestly.

What’s the barrel and build info?
It's an Ace Barrel: 6mm, SP3, 7.5 Twist 22" Finish Wrought Iron Fluting. Tikka Chambered by UM. I've already DCI'd the assembly a few times, new Rokstock, first one had internal cracks, acetoned, loctite and torqued to spec rings, piccatiny, action screws on reassembly.

Speeds are 3400 in the lands and 3250 at .030" Jump. 61 N570.

I have H1000 I could try. No 6mm Bergers but that might be the next step.
 
I’ve been struggling to find a load my new 6 PRC likes with the 109’s. I have tested .010” Jam, Lands, .010”, .020”, .030” and .030” jump and have not gotten any better than MOA out to 600 yards. I am using 61grs of N570 measured to the kernel, runout is good, neck tension is good.

One thing I just noticed is the tip concentricity of the 109’s is terrible from bullet to bullet. I just compared to some 108’s and it is night and day. Anyone ever see the same thing?

Next question, would it really matter?

I sent back some 140eldm before for what I would call excessive runout on the tips. They told me it wasn’t a big deal, but they shot like crap and left me wondering.

They replaced the bullets, never said what their findings were.

Iv never been overly impressed with the consistency of the eldm/x line but they do exactly what I want on animals so I will continue to use them for hunting.
 
It's an Ace Barrel: 6mm, SP3, 7.5 Twist 22" Finish Wrought Iron Fluting. Tikka Chambered by UM. I've already DCI'd the assembly a few times, new Rokstock, first one had internal cracks, acetoned, loctite and torqued to spec rings, piccatiny, action screws on reassembly.

Speeds are 3400 in the lands and 3250 at .030" Jump. 61 N570.

I have H1000 I could try. No 6mm Bergers but that might be the next step.
I think you’re too hot, try backing it down to 3200 fps in a 22” with the 108 or 109. I would also jump them .050 to .060”. N565 has given me the best results in my 6prc’s.
 
I’ve been struggling to find a load my new 6 PRC likes with the 109’s. I have tested .010” Jam, Lands, .010”, .020”, .030” and .030” jump and have not gotten any better than MOA out to 600 yards. I am using 61grs of N570 measured to the kernel, runout is good, neck tension is good.

One thing I just noticed is the tip concentricity of the 109’s is terrible from bullet to bullet. I just compared to some 108’s and it is night and day. Anyone ever see the same thing?

Next question, would it really matter?
What are you using for primers? I started with Fed 210 and changed to CCI BR2 and there was a difference in group sizes. I don't understand why there is a difference. I always try different primers if a load isn't where I want it to be.
 
I also ordered some 109s to play with over the weekend. I will post the results once I get out.
 
I’ve tried WLRM, 215m and 210m primers. No discernible difference. I am still moving out in seating depth and will drop velocity to 3200.

My OCD will not allow me to ignore that stupid little plastic tip. Just rolled 50 bullets on a very flat surface and only found 10 that rolled true. Upon further inspection, some of the tips are loose and can be moved around. I’m sure loading from a magazine imparts enough force to change every round upon chambering. Now I’m gonna have to hand feed some known rounds with trued tips and see if that’s the problem.
 
I’ve tried WLRM, 215m and 210m primers. No discernible difference. I am still moving out in seating depth and will drop velocity to 3200.

My OCD will not allow me to ignore that stupid little plastic tip. Just rolled 50 bullets on a very flat surface and only found 10 that rolled true. Upon further inspection, some of the tips are loose and can be moved around. I’m sure loading from a magazine imparts enough force to change every round upon chambering. Now I’m gonna have to hand feed some known rounds with trued tips and see if that’s the problem.
I wouldn’t even mess with them at that point. You’ll never have confidence in them and the extra .03 G7 isn’t worth the headache of sorting bullets and single feeding IMO.

I think I have a decent amount of 109’s here, and mine seemed fine. I’ll just send you 100 to test out if you PM your shipping info 🤙🏼.


But yes hornady ELDM’s in general are pretty inconsistent lot to lot as well as bullet to bullet. They just kill really well lol. I have two different lots of 180 ELDM’s that might as well be different bullets all together. I don’t even know how they could vary so damn much.
 
I think you'd be surprised. I had a rifle that went over 2" by shot number 7 with H4831SC and then stacked 10 into an inch with H4350. But I agree some barrels just don't like a certain bullet.
Yeah I always test different powders before I do anything at all. One normally stands out above the rest, but normally everything shoots decent. I just haven’t seen it THAT drastic.
 
I’ve tried WLRM, 215m and 210m primers. No discernible difference. I am still moving out in seating depth and will drop velocity to 3200.

My OCD will not allow me to ignore that stupid little plastic tip. Just rolled 50 bullets on a very flat surface and only found 10 that rolled true. Upon further inspection, some of the tips are loose and can be moved around. I’m sure loading from a magazine imparts enough force to change every round upon chambering. Now I’m gonna have to hand feed some known rounds with trued tips and see if that’s the problem.

Barrel is gonna be burnt out before you convince yourself your barrel just isn’t a shooter. UM has a half MOA guarantee right? Use it.
 
Barrel is gonna be burnt out before you convince yourself your barrel just isn’t a shooter. UM has a half MOA guarantee right? Use it.
This was my initial thoughts as well. But I always like to see if I’m wrong, and if something random brings the rifle together and what the catalyst was. So I always like to see more testing also.

6mm’s are about as forgiving as it gets to shoot small groups. Which is where my initial concern comes from.

The first 5 rounds down my last 6 PRC’s barrel was like a .4” group. I would shit if it was 2 MOA honestly.
 
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