88 ELD velocity nodes

[linebaugh]

I am cutting a new chamber in this weekend and am looking for input on velocity nodes for accuracy with the 88 ELD.
I would assume I can hit any velocity from 3000-3150fps but would think for the cartridge and powder combo my sweet spot on case fill and pressure will be at 3100 fps. Is anybody on here running them at pinpoint accuracy in the range above? Thanks.

 

[BCBRAD]

A 'node' has to do with the barrel length and barrel material. Chrome -moly and stainless steel barrels vibrate at 18-19,000 ft/s. There are usually 2 useable barrel times (mS). An example for a 24" bbl would be 1.1016 and 1.2282 mS, the higher value being the lower node as the bullet takes longer to get to the muzzle.
So , to say what 'x' velocity will be on a node is not a good way to express an accurate load as the acceleration rate of the bullet differs with component changes. I have found changing bullets , powders etc the velocity to coincide with the node I'm after is usually within 50 ft/s of each other.
Upon ignition of the powder charge the barrel starts to vibrate from source to muzzle and back, the vibration pattern is annular (invision a donut traveling out and back on the barrel) the bullet needs to be released from the muzzle when it is the calmest and tightest, in the example that would be at 1.1016 or 1.2282 mS.

So, the node is inherent to the barrel material, barrel length, and acceleration and exit time of the bullet. Velocity is a by-product.

 

[linebaugh]

A 'node' has to do with the barrel length and barrel material. Chrome -moly and stainless steel barrels vibrate at 18-19,000 ft/s. There are usually 2 useable barrel times (mS). An example for a 24" bbl would be 1.1016 and 1.2282 mS, the higher value being the lower node as the bullet takes longer to get to the muzzle.
So , to say what 'x' velocity will be on a node is not a good way to express an accurate load as the acceleration rate of the bullet differs with component changes. I have found changing bullets , powders etc the velocity to coincide with the node I'm after is usually within 50 ft/s of each other.
Upon ignition of the powder charge the barrel starts to vibrate from source to muzzle and back, the vibration pattern is annular (invision a donut traveling out and back on the barrel) the bullet needs to be released from the muzzle when it is the calmest and tightest, in the example that would be at 1.1016 or 1.2282 mS.

So, the node is inherent to the barrel material, barrel length, and acceleration and exit time of the bullet. Velocity is a by-product.

All the shooting I have done I never looked into this much, and appparently for good reason. I have enough "other stuff" to worry about and don't want to make room for that in my little pea brain.
Sounds like I just do like always and shoot for what I consider optimal and go from there. Was just trying to fast track as I won't have much time between matches this time.

Thank you for the response.

 

[BCBRAD]

All the shooting I have done I never looked into this much, and appparently for good reason. I have enough "other stuff" to worry about and don't want to make room for that in my little pea brain.
Sounds like I just do like always and shoot for what I consider optimal and go from there. Was just trying to fast track as I won't have much time between matches this time.

Thank you for the response.

I use QuickLoad to do the math for me, the QL program does take 'study 'to operate correctly. Usually a load can be found within 5 shots. Inputs to the program need to be exact, weights measures, and velocities. As does an understanding of internal ballistics.

Certainly not for everyone, I only know 3 others loading to the strict rules of QL, OBT and OCW in my area.

Fellow competitors say ~ 2930 ft/s for a 6 Dasher/ 105 class bullets in a 26" bbl works really well with Varget.......I run mine at ~2880 ft/s with H-4350

Just an easy way of getting a good load fast, after all the ground work is done.

 

[Ranger188]

Is this for a 22br?

 

[linebaugh]

Is this for a 22br?

22 gt

 

[Ranger188]

Nice, hopefully it's the right blend of not to much powder and not enough
to burn the barrel out early and still get 3100fps and make a good shooter.

 

[Evan]

I imagine that 3100 from a 30" barrel 22GT will happen at nice low pressure. 3075fps is a warm but conservative load in my 28" 22BR with headroom above it. If you step on it, I wouldn't be surprised to see it hit 3300 or more.

 

[linebaugh]

The reason I wont hit anything above 3150 is powder choice. I can't go over 3200 fps anyway so that's a no go on both counts.

 

[xswanted]

A friend is running them at 3085 from a 22creed with excellent accuracy.