Alright so I finally found some time to sit down and get my first rounds loaded and fired these past two days. The load development and test method I used was "velocity node", just plain shooting at a berm over my magnetospeed sporter.
Here is load data:
Bullet - 85gr TREX tipped
Brass - once fired hornady
primer - CCI 450
powder - H335
brass length - 1.515
CBTO - avg 1.674 (had some slight fluctuation based on Ogive inconsistency, but only by a thousandth here or there)
COAL - avg 2.267 (min - 2.263/max - 2.270)
I measured my 10rd Durmag and figured I would be fine with a max 2.270, but did experience a feeding issue on one of the 2.269 cartridges. Think I may back down to 2.250 since this is where he designed the the bullet to seat. This will put me 0.073" off the lands.
Starting load 28.0gr increase by 0.2gr to a max of 31.8gr (20 rounds). Each charge will be accompanied by its velocity.
28.0 --- 2563
28.2 --- 2571
28.4 --- 2603
28.6 --- 2624
28.8 --- 2640
29.0 --- 2647
29.2 --- 2663
29.4 --- 2681
29.6 --- 2721
29.8 --- 2766
30.0 --- 2757
30.2 --- 2794
30.4 --- 2791
30.6 --- 2829
30.8 --- 2821
31.0 --- 2895
31.2 --- 2904
31.4 --- 2925
31.6 --- 2945
31.8 --- 2987 (only round I saw a pressure sign, light ejector mark)
Looks like I had a pressure spike between 30.8 and 31gr (74fps) ejected brass looked fine, no excessive pressure signs.
I don't see a super clear "node", although 30.2 and 30.4 caught my attention, looking at others data for similar testing method there seems to be a node of 3-rounds that have a similar FPS. All of the "nodes" that show similar fps (2-8 fps change) are 2-round based. There is only one exception that I found today, where he used a 2-round sample for their velocity node.
Any advice on the above data would be appreciated.
My next step is to potentially "redo" a smaller sample size since I know now that 31.6 is my max with no pressure signs and work backward. Load another 10-rounds start at 29.8gr, increase 0.2gr to reach 31.6gr. See if I can re-create the node at 30.2 and 30.4 but to see if the same pressure spike shows up between 30.8 and 31.0.
This all makes sense in my head, but would like some experienced opinions from the Horde. Please let me know if something looks off, dangerous, wrong, etc.
PS - I did recover more than half of the projectiles from the dirt berm I shot into at 100yrds+/- all opened up beautifully.
Here is load data:
Bullet - 85gr TREX tipped
Brass - once fired hornady
primer - CCI 450
powder - H335
brass length - 1.515
CBTO - avg 1.674 (had some slight fluctuation based on Ogive inconsistency, but only by a thousandth here or there)
COAL - avg 2.267 (min - 2.263/max - 2.270)
I measured my 10rd Durmag and figured I would be fine with a max 2.270, but did experience a feeding issue on one of the 2.269 cartridges. Think I may back down to 2.250 since this is where he designed the the bullet to seat. This will put me 0.073" off the lands.
Starting load 28.0gr increase by 0.2gr to a max of 31.8gr (20 rounds). Each charge will be accompanied by its velocity.
28.0 --- 2563
28.2 --- 2571
28.4 --- 2603
28.6 --- 2624
28.8 --- 2640
29.0 --- 2647
29.2 --- 2663
29.4 --- 2681
29.6 --- 2721
29.8 --- 2766
30.0 --- 2757
30.2 --- 2794
30.4 --- 2791
30.6 --- 2829
30.8 --- 2821
31.0 --- 2895
31.2 --- 2904
31.4 --- 2925
31.6 --- 2945
31.8 --- 2987 (only round I saw a pressure sign, light ejector mark)
Looks like I had a pressure spike between 30.8 and 31gr (74fps) ejected brass looked fine, no excessive pressure signs.
I don't see a super clear "node", although 30.2 and 30.4 caught my attention, looking at others data for similar testing method there seems to be a node of 3-rounds that have a similar FPS. All of the "nodes" that show similar fps (2-8 fps change) are 2-round based. There is only one exception that I found today, where he used a 2-round sample for their velocity node.
Any advice on the above data would be appreciated.
My next step is to potentially "redo" a smaller sample size since I know now that 31.6 is my max with no pressure signs and work backward. Load another 10-rounds start at 29.8gr, increase 0.2gr to reach 31.6gr. See if I can re-create the node at 30.2 and 30.4 but to see if the same pressure spike shows up between 30.8 and 31.0.
This all makes sense in my head, but would like some experienced opinions from the Horde. Please let me know if something looks off, dangerous, wrong, etc.
PS - I did recover more than half of the projectiles from the dirt berm I shot into at 100yrds+/- all opened up beautifully.
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