Are these multiple nodes possible

[mugsie]

I was working up a load for my 308 the other day using Hornady 155 A-Max bullets, R&P Brass, CCI 200 promers and IMR 4064 powder. I had three each loaded with 43grains, 44, 45, 46 and 47 gains of powder. The IMR website maxes out at 47.5 but I decided to stop at 47.

Anyway, my first three shots, at 43 grains, had two almost on top of one another and the third off upper left about 3/8 to a 1/2 inch. The 44g group had spread out to a triangle about an inch, the 45g group had two in virtually the same hole and one lower right about 1/4" down (I think I pulled this one), the 46g spread out again and the 47g group had three touching one below the other in a small verticle string.

It seems the nodes are at 43, 45 and 47 grains, or every two grains. Does this seem right? Can there be that many nodes this evenly spread out? I'm going to now work up the load around the 45 grain mark, maybe 44.7, 44.9, 45.1 and see what that does.

For those of you shooting 4064 - do any of you use 155grain bullets and what are you finding in the way of powder volume? I also use BLc-2, and Varget, but am not interested in them - only in the 4064 comments, so please hold it to that only.

Thanks all.....

[Nor Cal Mikie]

It's been my experience that you'll find two accuracy nodes. One higher and one lower. I prefer to stick with the "lower" nodes. Leaves you more wiggle room if you run into a temp change and your brass will last longer if you're not pushing
for the higher pressure all the time.
Makes no difference which powder you're using, the nodes are there.
I would work with a 1/10th change in powder around the 45 grain load as you get real close in accuracy.
And make sure you only change "one thing" at a time or you'll end up chasing your tail. JMHO and that's what works best for me, Mike.

[82boy]

Typicaly you will find 2 nodes. As mention one high and one low. You are looking for the area where the barrels is moving in the right frequency to have the ultimate accuracy. Unlike the aformentioned poster I always shoot the higher node, as I have found that with the lower node, it has a tendency to go out of tune quicker, and is more affected by wind, than the higher node is.

You may want to play with seating depth, and then retry the loads again. I typicaly want to shoot 3 shoots all in the exact same hole, (Group measuring in the .0 to .1) if they are not all in the same hole, then I keep changing things (Powder ((both weight and type.)), Bullets, primers, seating depth ETC.) untill it will. If your shooting 3 shot groups in the 3/8, 1/4 or 1/2 inch area you have not hit the node.

[mugsie]

82boy - three in the same hole? What rig are you using? I'm benched, have a Caldwell rest on the front but I'm holding on a bag in the rear. There is some wiggle room, which is caused by me. If I shoot three touching I figure that's about as good as I'm going to get it. I'm also using a McMillan stock, not the best, but more than adequate for my needs. What might you recommend both in the way of technique and in loads? what components are you shooting?

[82boy]

82boy - three in the same hole? What rig are you using? I'm benched, have a Caldwell rest on the front but I'm holding on a bag in the rear. There is some wiggle room, which is caused by me. If I shoot three touching I figure that's about as good as I'm going to get it. I'm also using a McMillan stock, not the best, but more than adequate for my needs. What might you recommend both in the way of technique and in loads? what components are you shooting?

I would expect this accuracy out of any rig I have. Think about it this way, Almost every Savage rifle I have ever shot will shoot a 5 shot group at around a 1/2 Inch at 100 yards, so with that said ,If your 3 shot groups are at 1/2 inch it is dang near impossible for it to shoot a 5 shot group the same. Remember 3 shots groups prove the load 5 shots prove the shooter. As far as rigs goes, I have done this with right out the box tupperwere stocked guns (12FV, 11F, ETC) higher end guns (12 bechrest, 12 precision carbine) and lower end guns such as the axis. I have doen it shooting off of bi-pods, sand bags filled with corn cob media, and mechanical rest, all using just a simple rear bag.

My high end benchrest guns which I expect them to shoot 5 shoot groups around and/or under .2 everytime, is basicly set up on a similare set up to what you have. I shoot off of an old hart rest, with a cheap old protektor 13 rear bag, nothing fancy. Your calwell rest with a rear bag and mc millan stock is pleanty capible of shooting small groups, with 3 shots in the exact same hole. There should be no wiggle in that rig at all.

To start on technique, if you not using wind flags you are totaly wasting your time. Be comfortable, keep your feet flat one the ground, set the rifle up for your body to be stress free, have the scope set back far enought you not having to strech out your body to get a sight picture. Make sure your seat is positioned well, not to low, and not to high. Make sure the scope is paralax free, this is done by moving your head around if the target moves, or the cross hairs move then you have paralax. Watch for light changes IE when the clouds come and go. The most important of all is to pratice, nothing replaces trigger time.

On your loads, there will be a small window, on powder charges in both nodes, the most important is seating depth, it is either right or wrong. When you find a change that looks good investigate more around it. you said that 45 grs you have 2 in the same hole, and you believed you pulled the last shot, play around with this load more, try 44.5grs and try 45.5 see which one looks better then split the diference if 44.5 looked better than 45.5 then try 44.7, if you see improvement then try 44.6, 44.8, and 44.9.

[82boy]

Further examples.
5 shoots at 100 yards shot from a box stock edge in 22/250 offof a by pod, and rear bag.


5 shoots at 100 yards, with a box stock model 12 bechrest off of a heart rest and rear bag.


5 shoots at 100 yards shot from a model 10 PC off of a caldwell rock Br rest and rear bag.

[mugsie]

I'm suitably impressed!

[lal357]

82 boy is correct find the node that looks the best and go up and down .5gr. Each way the look at those and do it again I also shoot them more than once to make sure it wasn't a fluke . I see a lot of people shoot and are happy with 1" groups at 100 yds they are not loading there rounds to there full potential. It can be something as simple as seating depth of the bullet happened to me with my .223 I was grouping around 2.5" at 300yds tried everything I could think of then I changed the seating depth and if I do my part can put 5 into 3/4"

[Nor Cal Mikie]

Only problem with going .5 grains at a time is you may jump past the sweet spot.
If you get close, try .1 grain change.