Usually on the giving end of advice...need help

[Bang4theBuck]

So, I built a custom 6x284 with a 26' carbon barrel. The rifle is showing lots of promise on the accuracy front with the reloads, but I am getting velocity spreads that are well outside the norm as compared to all of my other reloads. I have tried 3 different bullets, and two different batches of brass. Looking for the "smoking gun' reason why the spreads are so high.
Started with Lapua 6.5x284 brass necked down to 6x284, then neck turned. While I was trying to just skim turn them, I managed to reduce the neck thickness to .011". After firing, the necks had expanded around .010" over the loaded outside dimension. Assuming that was my problem with velocity consistency, I canned that brass and bought new petersen brass and necked it down to 6x284. Still I am getting some very high extreme spreads (40-65 fps).
I am using RL26, BR2 primers and I've shot Berger Hunting Hybrids, Hornady ELDX and Hammer hunters. All with the same high extreme spreads. I've meticulously checked and rechecked my powder weights, checked all the necks for concentricity, verified good primer seating, etc.

I am wondering if this charge of powder and primer combo are a little incompatible? Woukd moving up to a magnum primer help? Is this common woth the first firing of a necked down case to be this way?

Thoughts?

 

[L.Sherm]

So, I built a custom 6x284 with a 26' carbon barrel. The rifle is showing lots of promise on the accuracy front with the reloads, but I am getting velocity spreads that are well outside the norm as compared to all of my other reloads. I have tried 3 different bullets, and two different batches of brass. Looking for the "smoking gun' reason why the spreads are so high.
Started with Lapua 6.5x284 brass necked down to 6x284, then neck turned. While I was trying to just skim turn them, I managed to reduce the neck thickness to .011". After firing, the necks had expanded around .010" over the loaded outside dimension. Assuming that was my problem with velocity consistency, I canned that brass and bought new petersen brass and necked it down to 6x284. Still I am getting some very high extreme spreads (40-65 fps).
I am using RL26, BR2 primers and I've shot Berger Hunting Hybrids, Hornady ELDX and Hammer hunters. All with the same high extreme spreads. I've meticulously checked and rechecked my powder weights, checked all the necks for concentricity, verified good primer seating, etc.

I am wondering if this charge of powder and primer combo are a little incompatible? Woukd moving up to a magnum primer help? Is this common woth the first firing of a necked down case to be this way?

Thoughts?

I would start with a 210 primer, and then a mag if you have them. After that more grip on the bullet like .003 - .004.
If that doesn't work switch powder.

 

[Petey308]

What kind of chronograph are you using? Normally a man ES that high is a sign that something is very inconsistent with your ammo. It's not usually from a bad powder, bullet, primer combo.

I wouldn't think it's your brass either if you're using new Peterson brass and it still does that.

Either your chronograph is messing up, or you're inducing some sort of inconsistency you're unaware of and need to pinpoint via process of elimination.

 

[sedancowboy]

Sherm gave good advice. I would add that with that much of a overbore I would go to a slower powder and mag primer. While I use a lot of RL-26 and love it. It does not function is really well with over bores sometimes.

 

[Barbourcreek]

Try fed 210 primer
Your other primer might be breaking loose the bullet from a intense charge

We see this with 215 primers in a 28 nosler so we use 210

Primer being explosive may be dislodging the bullet from higher compression before propellent burn build up

 

[Bang4theBuck]

What kind of chronograph are you using? Normally a man ES that high is a sign that something is very inconsistent with your ammo. It's not usually from a bad powder, bullet, primer combo.

I wouldn't think it's your brass either if you're using new Peterson brass and it still does that.

Either your chronograph is messing up, or you're inducing some sort of inconsistency you're unaware of and need to pinpoint via process of elimination.

Using a magnetospeed V3. Used it for years. Battery is fresh, and used it the same day on a Dasher and it reflected single digits on everything.

 

[L.Sherm]

Using a magnetospeed V3. Used it for years. Battery is fresh, and used it the same day on a Dasher and it reflected single digits on everything.

Its not your chrono.

 

[Bang4theBuck]

Gents are you saying that the BR2s are more intense than 210s?

 

[Bang4theBuck]

Also, I do have H1000, but it is only slightly slower than RL26. Are there other characteristics of these powders that might make the H1000 better than the RL26 in this case?

 

[Petey308]

Also, I do have H1000, but it is only slightly slower than RL26. Are there other characteristics of these powders that might make the H1000 better than the RL26 in this case?

H1000 is a single base powder vs the double base RL-26, and a but more temp stable overall.

You can try it, but I'm not convinced that's your problem.

 

[L.Sherm]

Gents are you saying that the BR2s are more intense than 210s?

Wether there more intense or not 210 have worked out better for me than BR2 not saying BR2 won't work, but somethings not right with your combo.
If you have ever tested nk. tension you would be amazed just what .001 will do to a load and E.S.

 

[Bang4theBuck]

Wether there more intense or not 210 have worked out better for me than BR2 not saying BR2 won't work, but somethings not right with your combo.
If you have ever tested nk. tension you would be amazed just what .001 will do to a load and E.S.

I agree with you on that. Problem is in this case, is that the die selections were very limited, and I only have a redding full length sizing die, and an expander mandrel, which goes against what Sherm said about tightening the neck tension.

 

[Bang4theBuck]

I dont think I have 210s, but I'll check.

 

[L.Sherm]

I agree with you on that. Problem is in this case, is that the die selections were very limited, and I only have a redding full length sizing die, and an expander mandrel, which goes against what Sherm said about tightening the neck tension.

If you take the expander out how much you got, I would be afraid to try. 005