Txhillbilly, thanks for that advice.
To the range again I went. This time I had four sets of five each loaded at 2.9 CAOL. I will play with seating depth more later. Right now the bullets are touching the lands.
I loaded four sets at each of the following powder charges, again using 4064: 41.4, 41.6, 41.8, and 42 grains. The pictures below show the results. I did get two half inch groups. I'm still not satisfied, but we're getting there.
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Last edited by yew plucker; 04-25-2016 at 05:14 PM. Reason: grammer
I think I would go with the one that had the least vertical stringing, assuming you had a good rest, then play with seating depth.
The 41.6 and 41.8 groups are so close that I want to try a few groups 41.7, then play with seating. I'm pretty sure I'm gonna leave them seated out long, but back them off the lands a few of thousandths.
All groups were fired off a bipod with a rear bag.
I would also recommend using sand bags for front rest when doing load development. Tripods are handy in the field, but not the best for accuracy off a bench. If you must use them, you might also try putting a soft pad between the feet and bench.
Thanks for that advice, Foxx.
At 41.7 gr of 4064, it was all over the place again. I'm gonna back off to 41 gr and work up in 1/10th grain increments and we'll see.
I can't believe I had a factory varmint 10fp barrel that liked 44 grain's of IMR 4064. The coal was short, like 2.780, I believe it was a commpresed load.Originally Posted by yew plucker
The Shilen Select match .308 barrel I still have likes 41.4- 41.5 4064 with 168's and 178's.
My advise is to start out using brand new Lapua Palma .308 brass that use's small rifle primer's, it will last longer.
There really is an excuse for everything!
A couple of aspect here. 3/10 a grain is of no significance, so don't look for the variation in 1/10 powder charges (small 17 and 22s aside)
I have an old RCBS Junior press, I just keep it in the car with a C clamp. It goes to the range with me. I have one group of no less that 15 seated to a trial depth.
The rest are deliberately left long. I then use the press and the bullet seater die to tune things as they seem to come together or not. I carry the completion seater as I can see the adjustment.
I also have a bullet ogvie compartor and that is my bench mark, not the tip. Tips vary a lot, Ogive does vary but closer.
I don't bother to zero it (1 inch length), I just list in my books Ogive and its a given they are actually 1 inch longer than real. Its the difference more or less you want.
.005 is the smallest change. Ogive has enough variation its not going to change getting it any closer than that. Some will be a hair less and some a hair more but .001 does not make it work best or not.
My take on loads is that I start 5/10 grain above the minimum out of my two ref books (Sierra and Hornady) 15 of that, then adjust up 5/10, another 15 etc.
There should be an accurate node down in the lower end. I assume if its the lowest load the first one will be pretty good and then start to get worse.
There also should be another one at the upper end.
My best groups were at 41.6 and 41.8 of 4064. The length was 2.860 if I recall correctly. I have a few loaded rounds left and can try a few out touching the lands. That was a 2.94 COAL. I don't have an ogive comparator. I'll tell ya what I do see though, is that thee sierra bullets are MUCH more consistent than they were twenty three years ago when I started doing this. Bullet weights used to vary two or there grains above or below the target weight. Now that variance is measured in tenths of a grain. I am seeing the same kind of precision in bullet length also.
I'll try a few out to the longest length chamberable and see what that does. Will have to feed them singly, but so what?
I finally got the thing to shoot like I thought it should. I backed the load down to 40.5 grains and worked up, built up 5 rounds of each increasing at two tenths grain increments. So, 40.5, 40.7, 40.9 and 41.1 were the choices. The 40.5 grain load shot the best by far with three of the five clover leafed and two fliers which I called, giving me a half inch group over all. I was out of ammo for that range session. I need to confirm one more time before I call it good. But I believe the 40.5 grains of 4064 will give me the sub half inch groups I have been chasing.
So it looks like the Shaw barrel may not have been a such a bad investment after all.
To put it in perspective, my Shilen 06 barrel is listed as 3.220 for the COL when up to the lands it is actually 3.290.
If you want max accuracy in any gun that's the placed to start.
You then have to live with max accuracy or max mag length or see if it will shoot good from further back.
Berger on the VLDs say it can be as much as ,150 off the lands to shoot good.
Rifles are made by the mass average (and save, aka SAMMI) and if you want a custom gun then you have to pay for it.
My barrel is very tight as well so that is not a factor in this.
I bought mine knowing this and single load.
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