Accuracy Node Calculator - is there a free one somewhere ?

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Born Again
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Accuracy Node Calculator - is there a free one somewhere ?

#1 Post by Born Again »

I will soon be trying to work up a .308 load using bullets around 150 - 155gn, in an attempt to improve accuracy over my usual 168SMK at 700yds+ . I have never used an accuracy node calculator before, I'm wondering if it might save some time.


Is there one online somewhere ? Is it even worth trying ?


Any advice appreciated.
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Ovenpaa
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Re: Accuracy Node Calculator - is there a free one somewhere

#2 Post by Ovenpaa »

The 168SMK is not particularly great once you get out beyond 600-700 and I have not come across an accuracy node calculator so would be interested to see one.
/d

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Born Again
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Re: Accuracy Node Calculator - is there a free one somewhere

#3 Post by Born Again »

Ovenpaa wrote:The 168SMK is not particularly great once you get out beyond 600-700 and I have not come across an accuracy node calculator so would be interested to see one.

I haven't seen or used one either, but given my infrequent access to long range I'm hoping to gain a few clues to help work up a good load. In truth, I have a feeling there is no substitute for conventional development, but I'm open to new ideas.
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Re: Accuracy Node Calculator - is there a free one somewhere

#4 Post by Ovenpaa »

My 'GoTo' loads for many years have been Lapua brass, Scenar 155 projectiles Fed210M primers and N140 or alternatively 170LB projectiles and N540 (Rifle dependant) They work to great effect outside of F/TR type meetings. Accuracy comes with load development, shooting style, wind reading and a generous helping of luck :)

No doubt the next reply will advocate the SMK #2166 or the Berger 185 or whatever with an IMR powder or Varget or whatever. I think the trick is fins something that works for you and you can repeat and be prepared to spend some time on the matter.

There are exceptions. Many years ago we shot with a chap who purchased a new TRG22 and proceeded to throw rounds into the 5 ring and V with his first outing, we asked him when he had done his load development and he replied he had not had time, so had searched the internet and taken the average of the 'accurate' loads across the sites. it was 40 something grains of N140 and SMK #2155 bullets from memory.
/d

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Re: Accuracy Node Calculator - is there a free one somewhere

#5 Post by @nd »

Is this something like what you were looking for.(Hope you can open it)
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Re: Accuracy Node Calculator - is there a free one somewhere

#6 Post by Duey »

Need to get to 155s to at least 2800fpr for an accurate load, if you have a longer barrel then you may get as much as 3000fps
The average load of Vhit N140 with 155s seems to be 46gr but obviously you would need to develop up to this dependant on length of bullet etc etc as it is probably above the loading manuals max level

I personally got better results with 155 scenars behind 46gr N140 with. 26” barrel and speed was around 2850fps, cannot remember what COAL was for the built bullet but I remember it was built to within 10 thou of lands

Hope this helps
Born Again
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Re: Accuracy Node Calculator - is there a free one somewhere

#7 Post by Born Again »

Thanks for the pointers. I'm glad to see N140 mentioned as that's what I'm currently using (42.9gn, 168SMK, 71mm OAL, Fed210M). I also have a tub of RL15 unopened.
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Re: Accuracy Node Calculator - is there a free one somewhere

#8 Post by Ovenpaa »

What is the rifle and barrel length?
/d

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Re: Accuracy Node Calculator - is there a free one somewhere

#9 Post by pe4king »

Every .308 rifle I have ever owned had been outstanding with 46gr of N140 and what ever flavour of 155gr bullet, then just play around with the C.O.A.L my AW for instance loves 2.870”
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Born Again
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Re: Accuracy Node Calculator - is there a free one somewhere

#10 Post by Born Again »

Ovenpaa wrote:What is the rifle and barrel length?

It's a Ruger Model 77 Mk1, 22" barrel. Not a target rifle, but in good condition and seems to shoot well with loads towards the top end, maybe because of the 1 in 12" rifling. I use Lee loading kit with a Lee collet type neck sizer. Brass is Remington. I used to have it as a "scout" type rifle, but with an eye on trying longer range I have fitted a Leupold VXIII 6.5-20 x 50 LRT.


The Ruger will probably get replaced with something more suitable eventually, but I reckon the lessons I learn now will be useful in future, whatever rifle I buy.
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