Well, changing the bullet changes things.

For instance, my 260 likes 42.4 grains H4350 under berger 140 hybrids, with COAL at 2.836

That same rifle prefers the Lapua Scenar 139 gr at 41.6 gr h4350, COAL at 2.800

Both determined using the OCW method, separately.

You ought to get there. The gun looks like it wants to shoot.

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Here are closeups. My biggest concern is shift in POI vs. POA. I did shoot 24 rounds within 30 minutes so the barrel was pretty hot.

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And that is the point of the OCW test. If you truly had it on the OCW for that rifle/bullet/powder/brass combo, you would have minimum POI shift with the barrel and powder Temps changing.

I would get some Berger 140 or Hornady Amax and run the OCW again. I can send you some of both if you send me your address.

Just gonna throw in an opinion and it can be taken for whatever it's worth. IMO if a person id trying to work up a 1000 yard shooter, spending anymore time at 100 yds other than to boresight and get it on paper, is a waste of time. You don't need a rifle that can shoot less than 0.1 groups at 100 yards to be competitive at 1000 yards. VLD bullets often do not shine until 300 yds since they may not fully stabilize inside 100 yards. The 300 yard-line is where you can assess whether a rifle has what it takes to do well at 1000. If you can group at or under 1 at 300 yards, you'll be in the running at 1000 yards. But to reach this level, you need ultra-consistent ammo, proper shooting technique, and a rifle that shoots straight. Very, very straight. If you're not able to cover a 5 shot group at a 100 yds with a dime, you're in deep trouble at a grand.

Now troubleshooting is great regardless of the distance, but you have to stick to as few variables as possible. DO NOT change more than one thing at a time.

Pistol,

That would be great. what is your email address?

Barnes

I have decided to do what I should have done in the first place. I am starting over and shooting a completely new OCW tomorrow. I am loading 3 shots each using the 140g Hornady Match seated to a COL of 2.800. I started at 41.5g and I am going up .3g at a time. So 41.5. 41.8, 42.1, 42.4, 42.7, 43.0, 43.3, and 43.6. I was going to run this at 100 yards and see what my OCW is. Are you suggesting that I run this OCW at 300 yards? If that is the case, would it not be better to just run a ladder test at 300? If what I am planning to do is not the best option feel free to tell me.

72

I'm not going to knock on Newberry, it's just not my cup of tea.

I'm more of a ladder guy personally, and I'm more concerned with OBT and harmonics of the barrel, to fine tune a load for serious distances. I concentrate on node timing and barrel whip, and adjust my velocity to optimize the bore contraction at the time the bullet passes through the last 6-8 inches of the barrel at the muzzle, to give the projectile optimum stabilization at the time is leave the bore.

Simply put I've never really found a use for Newberry's method for extreme range work. You can run your OCW at 300 yards, and if the groups you posted were from 300 I would have had something to consider, but those were all over the place. To me OCW just beats around the bush too much and leaves too much to interpretation. Like I said I'm not going to knock on Dan he's a decent guy, and he adds to the sport in a positive way.

Once I have my charge narrowed down I start tweaking the ballistic coefficient with seating and case trimming, being certain all the bullets are match weighed as close as possible, Bergers are less sensitive than the others to seating. I also work with fire formed brass instead of virgin brass, just get better more accurate results, with fire formed brass. Make dang sure your chronograph is reading right also.

The Ladder test is just another way to skin the same cat. I like the OCW simply because I don't have anytime access to a long range. so for me, A ladder test at 100 yards is useless.

some like to do both, meaning do a ladder test for the whole charge spectrum, and then do an OCW with .1 increments centering on the ladder test results.

trouble with the Ladder test by itself is that for the first trial, 300 yards will be fine, but then to narrow it down, you will need an even longer range, since the charges will be so similar, they wont seperate enough to get a good read.

And Shag I can appreciate that.

But back to my original point, to me, any data gathered at 100 yards "IMO" is about as worthless as boresighting when it comes to 1000 yd match shooting. It gets you on paper but that's about it. But that's me.

I'm not saying anything is right or wrong, do whatever works for you.

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Barnes

I have decided to do what I should have done in the first place. I am starting over and shooting a completely new OCW tomorrow. I am loading 3 shots each using the 140g Hornady Match seated to a COL of 2.800. I started at 41.5g and I am going up .3g at a time. So 41.5. 41.8, 42.1, 42.4, 42.7, 43.0, 43.3, and 43.6. I was going to run this at 100 yards and see what my OCW is. Are you suggesting that I run this OCW at 300 yards? If that is the case, would it not be better to just run a ladder test at 300? If what I am planning to do is not the best option feel free to tell me.

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You need to get you a modified case and gauge. 2.8" may be a good number, but it's completely arbitrary and could very well be a major source of your angst with this rifle simply because you don't know what the bolt face to lands measurement is.

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Barnes

I have decided to do what I should have done in the first place. I am starting over and shooting a completely new OCW tomorrow. I am loading 3 shots each using the 140g Hornady Match seated to a COL of 2.800. I started at 41.5g and I am going up .3g at a time. So 41.5. 41.8, 42.1, 42.4, 42.7, 43.0, 43.3, and 43.6. I was going to run this at 100 yards and see what my OCW is. Are you suggesting that I run this OCW at 300 yards? If that is the case, would it not be better to just run a ladder test at 300? If what I am planning to do is not the best option feel free to tell me.

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You need to get you a modified case and gauge. 2.8" may be a good number, but it's completely arbitrary and could very well be a major source of your angst with this rifle simply because you don't know what the bolt face to lands measurement is.

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This cannot be said enough, this is a measurement you absolutely have to have. You can even poorboy it and get a good number with a cleaning rod and and some bump stops

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But back to my original point, to me, any data gathered at 100 yards "IMO" is about as worthless as boresighting when it comes to 1000 yd match shooting. It gets you on paper but that's about it. But that's me.

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Yes, 100 yard information would not help you hit at 1000, no way to know your come ups.

But, all other things being equal, If you have one load that shoots .25 MOA, and another that shoots 1.25 MOA at 100 yards, I am absolutely convinced the first load will perform better at 1000 than the other.

Okay OB...I hear you about the test case to determine distance to lands. I will get that for sure.

In the meantime...I ran an OCW today. I waited approximately 2 minutes between shots. Below are my results. Take a look and tell me where you see my OCW? I will post my opinion in my next reply as to not skew your thoughts.

Again...here are details of the load.

Fireformed Lapua cases
CCI BR2 primers
H4350 Powder
Hornady 140g Match HPBT
COL 2.800 (I know...arbitrary)

















So What say you OB? What is my OCW?

what's the exact length of your barrell? and is it a varmint or bull?

26" bull barrel. Threaded. I run an AAC supressor.

Length including the Suppressor?

Maybe because the barrel is threaded its throwing off the harmonics and causing inaccuracy. Just a guess. I've read of this happening before.

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Maybe because the barrel is threaded its throwing off the harmonics and causing inaccuracy. Just a guess. I've read of this happening before.

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But that is tunable with charges based on velocity at the muzzle

However I'm not a fan of suppressors, for the very reason they throw of the OPT of the barrels original design, and not worth the headaches to work around it, vs the actual gain. It can be tuned around, it just takes some work.

naked eye, 42.7, but plotting it shows what it really is, looks to me like you have the coordinates...

That's true. I would shoot it without the suppressor. Also the gunsmith could have messed up the thread job

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That's true. I would shoot it without the suppressor. Also the gunsmith could have messed up the thread job

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stop. all he needs to do is shoot some groups varying the COAL and you will see some good groups forming.

I'm more fond of the 43.6 group and based on calculated OBT 43.5 should be calculated optimum for that barrel length. That's just my opinion, I'd really like to see some 300 yd groups to really dive a little better prognosis, but you are definitely in the ballpark. My recommendation would make sure you're .020 off the lands and see where you are, it was a really cool day today so there is going to be some variables at stake here. In July your best loads may be 41.5.

I personally think you have a decent shooter it just needs some tuning. At 43.6 you should be in the ballpark of 2710 fps +/-.

42.1 is interesting as well, just reading the verticals, but it's really tough without some solid chronograph numbers with me. Some case tuning and seating will bring the cream to the top.

Barnes...I shot 8 rounds with 43.5 over my Magnetospeed. Avg. of 2878 ft/sec with a S-D of 8.

So should I load 43.6 and try it .02 off the lands or load 43.5?

What did the OCW determine? Which load is has the least POI movement around it?
I'm on mobile so I cant really compare well.

What I am saying with the COAL trials is you should try .01 off the lands, .02 off the lands, .03 off the lands, etc. until you get back to 2.800. one of those, if you picked the OCW, will shoot the groups you want.

I believe it to be between 43.3 and 43.6

Ok, then I would try to confirm that with .1 increments across those loads. Then, with the OCW determined, I would shoot the COAL trials.

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Barnes...I shot 8 rounds with 43.5 over my Magnetospeed. Avg. of 2878 ft/sec with a S-D of 8.

So should I load 43.6 and try it .02 off the lands or load 43.5?

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Wow that's cooking pretty good, Let's stick with what you've done thus far, and not throw too many curves in the mix at one time. You have 43.6 already in your calc trials, I would stick with that, and concentrate on your coal now and hone in from there. Charge loads can be adjusted once you get the COAL adjusted. Ambient temperature changes are going to affect charge loads down the line, when you get out to 1000 yds anyway, but you are getting the foundation laid now.

Here is your calc chart for that barrel length for reference.

Barrel Length 26.0"

1st Node 0.8819 ms

2nd Node 0.9661 ms

3rd Node 1.1057 ms

4th Node 1.1905 ms

5th Node 1.3295 ms

6th Node 1.4149 ms

7th Node 1.5533 ms

H4350 won't be as affected as normal powders by ambient temperature. That's why it is so popular for competitive shooting with the 6.5's.

'72, IMO, you have a OCW test going, so why not see that to the end? If you don't like the results, you can try something else...

Tough to beat 4350 for all around good powder.

Sh****...what do I need to do to see it to the end other than adjusting COL?

Just determine the OCW from results, and adjust COAL to fiND the sweet spot.

after printing the page, 43.3 looks good, use that. or, if you want to get more precise, I would do one more mini OCW with these charge weights:

43.2
43.3
43.4
43.5
43.6
43.7


either way, once you choose your charge weight, do the COAL variations, and one (or more) of those will dial the group in for you.