CAUTION: The following post includes loading data not covered by currently published sources of tested data for this cartridge. USE AT YOUR OWN RISK. Neither the writer, The Firing Line, nor the staff of TFL assumes any liability for any damage or injury resulting from the use of this information.
This is my first time working up a rifle load, so I'm checking in to see if I am on the right track and where I should head next. This is for .223 Remington in an AR rifle.
I've done tests using 8208XBR under 55gr. sierra game king. I stepped up to the max load (25.8), where I saw the first indication of pressure.
I ran out 5 loads each @25.5 and 25.3 grains.
Prior to testing those I checked my zero with 20 rounds of factory ammo.
I am limited on what I can do for test firing right now, I'm limited to an indoor 25yd range. For support I used a front rest and was sitting on a stool trying to be very still...(Metalgod suggested leaning against the divider, I'll use that later).
What surprised me was that both loads shot a bit high and right. I figured I would see elevation differences, but I was surprised to see windage change.
There isn't a whole lot of difference in group size. The 25.3 is a bit tighter, but that could as well be me more than the load.
My plan was to run off 50 or so of the 25.3 and do the 4 hour drive to where I can to a 100 yard range and get into a prone position with some supports.
Any idea why the POI would move right over a factory load?
What should my next steps be?
[edit] I guess the disclaimer may not be necessary, but I thought I'd be safe
This is my first time working up a rifle load, so I'm checking in to see if I am on the right track and where I should head next. This is for .223 Remington in an AR rifle.
I've done tests using 8208XBR under 55gr. sierra game king. I stepped up to the max load (25.8), where I saw the first indication of pressure.
I ran out 5 loads each @25.5 and 25.3 grains.
Prior to testing those I checked my zero with 20 rounds of factory ammo.
I am limited on what I can do for test firing right now, I'm limited to an indoor 25yd range. For support I used a front rest and was sitting on a stool trying to be very still...(Metalgod suggested leaning against the divider, I'll use that later).
What surprised me was that both loads shot a bit high and right. I figured I would see elevation differences, but I was surprised to see windage change.
There isn't a whole lot of difference in group size. The 25.3 is a bit tighter, but that could as well be me more than the load.
My plan was to run off 50 or so of the 25.3 and do the 4 hour drive to where I can to a 100 yard range and get into a prone position with some supports.
Any idea why the POI would move right over a factory load?
What should my next steps be?
[edit] I guess the disclaimer may not be necessary, but I thought I'd be safe
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