Well, BigJW was able to get me going when I went out there this past weekend. Stayed up all night and built some loads to test (he also got me some Remington 7 1/2 primers that I've been needing for months... THANKS, JAKE!!).
I've only had access to Winchester 748 powder, so that's what I ended up going with.
The rounds:
Virgin Lapua 223 Match brass
Remington 7 1/2 primers
Winchester 748 Powder
Hornady 80gr AMax
OAL was set to 2.480"
The Lyman book suggested 2.550" for their 80gr HPBT. That was too long for my chamber and It took a few stuck bullets to find 2.480" to be a reliable OAL. Fired 70 rounds with no FTF or FTE issues. Started at 22gr and went up to 23.8. 24 was max in the book. No pressure signs, but with the length of the bullet coupled with the OAL, I'd be afraid of compressing the charge too much.
The following are the photos from groups 3 to 10 (I lost the paper for 1 to 2, but they were a little more spread than the 3rd group, which appears to be my best).
Unfortunately, there were a lot of factors going into this that makes me not believe the groups after 3 or 4. Namely, I had been at the range for 6 hours before I started the load work-up (training to be a RO), I was running at 36 hours with no sleep, and my head was pounding to the point that every time my heart beat while looking down the scope, the reticle would shift about 2 inches to the right (good 'ol Louisiana summer weather...). Top that with my lack of experience and trigger time... I don't think I can reliably say that the groupings got so wide because the load was bad.
Likely, I'll end up duplicating the test to verify when I'm not in 100 degree weather all day with no sleep. Anyways, enough with the excuses... time for the photos (you'll see the powder charge next to each group).
Range is 100 yards.
Groups 3 and 4
I kept notes during my strings.
*Note: Rushed 5th shot 4th string*
Groups 5 and 6
Pretty large difference from 3 to 5...
*Note: 1st shot 5th string- heavy vibration in tube and bolt slammed close on empty mag*
*Note: 5 minute rest between 5th and 6th string*
Group 7 and 8
*Note: Went cold, ran oil patch and brush down barrel before 7th string*
*Note: 7th String, 5th round flyer*
*Note: 8th String, 1st round flyer*... Upon inspection of the target, the first flyer was one off to the far right... being that there are two stacked there, I can't exactly call it a flyer.
Group 9 an 10
*Note: Went cold before group 9 and 10*
*Note: Quick couple passes with patch before group 10.
Obviously, the third was my best. 4 shots touching with one far low and right. I'm not sure what happened. Counting 4, I'm at .3MOA... counting the 5th, that brings it to .6MOA.
Like I said, I don't really trust myself with these groups. I'm going to run the test again before I decide. Preferably on a better day for it.
What are your thoughts?
Oh, and the note talking about the heavy vibrations and slamming closed on an empty mag (short stroking?) happened two or three more times.
One last thing: the trigger is a Geiselle high-speed national match 2 stage. I made a note that I rushed one of the shots. I don't actually think I did. The same thing happened a couple more times later in the test. I would being to take up the first stage and it would just fire. After it happened the first time, I was more careful to be on target before I started taking up the slack, but I thought it was very odd. Anyone have an idea what could be causing this?
I've only had access to Winchester 748 powder, so that's what I ended up going with.
The rounds:
Virgin Lapua 223 Match brass
Remington 7 1/2 primers
Winchester 748 Powder
Hornady 80gr AMax
OAL was set to 2.480"
The Lyman book suggested 2.550" for their 80gr HPBT. That was too long for my chamber and It took a few stuck bullets to find 2.480" to be a reliable OAL. Fired 70 rounds with no FTF or FTE issues. Started at 22gr and went up to 23.8. 24 was max in the book. No pressure signs, but with the length of the bullet coupled with the OAL, I'd be afraid of compressing the charge too much.
The following are the photos from groups 3 to 10 (I lost the paper for 1 to 2, but they were a little more spread than the 3rd group, which appears to be my best).
Unfortunately, there were a lot of factors going into this that makes me not believe the groups after 3 or 4. Namely, I had been at the range for 6 hours before I started the load work-up (training to be a RO), I was running at 36 hours with no sleep, and my head was pounding to the point that every time my heart beat while looking down the scope, the reticle would shift about 2 inches to the right (good 'ol Louisiana summer weather...). Top that with my lack of experience and trigger time... I don't think I can reliably say that the groupings got so wide because the load was bad.
Likely, I'll end up duplicating the test to verify when I'm not in 100 degree weather all day with no sleep. Anyways, enough with the excuses... time for the photos (you'll see the powder charge next to each group).
Range is 100 yards.
Groups 3 and 4
I kept notes during my strings.
*Note: Rushed 5th shot 4th string*
Groups 5 and 6
Pretty large difference from 3 to 5...
*Note: 1st shot 5th string- heavy vibration in tube and bolt slammed close on empty mag*
*Note: 5 minute rest between 5th and 6th string*
Group 7 and 8
*Note: Went cold, ran oil patch and brush down barrel before 7th string*
*Note: 7th String, 5th round flyer*
*Note: 8th String, 1st round flyer*... Upon inspection of the target, the first flyer was one off to the far right... being that there are two stacked there, I can't exactly call it a flyer.
Group 9 an 10
*Note: Went cold before group 9 and 10*
*Note: Quick couple passes with patch before group 10.
Obviously, the third was my best. 4 shots touching with one far low and right. I'm not sure what happened. Counting 4, I'm at .3MOA... counting the 5th, that brings it to .6MOA.
Like I said, I don't really trust myself with these groups. I'm going to run the test again before I decide. Preferably on a better day for it.
What are your thoughts?
Oh, and the note talking about the heavy vibrations and slamming closed on an empty mag (short stroking?) happened two or three more times.
One last thing: the trigger is a Geiselle high-speed national match 2 stage. I made a note that I rushed one of the shots. I don't actually think I did. The same thing happened a couple more times later in the test. I would being to take up the first stage and it would just fire. After it happened the first time, I was more careful to be on target before I started taking up the slack, but I thought it was very odd. Anyone have an idea what could be causing this?
