Finding good "node"

[7mmfan]

As I continue my quest to develop a load for my 7mm-08 that even vaguely resembles the accuracy I get in my 7 mag, I've come across this term several times. Many use it like a common term we should all just know. In my research, I've developed a rudimentary understanding of it, the idea of timing the exit of your bullet with harmonics that reach the end of your barrel at, or at nearly, the same time allowing the least amount of deviation of the bullet leaving the barrel, allowing for the best accuracy.

There appear to be methods of determining this without gross amounts of shooting and testing. Does anyone have any experience with this?

[Alan K]

QuickLoad seems to get me in the ballpark when first starting development, then I fine tune from there.

[7mmfan]

Quickload is a program that you need to purchase correct?

[Magnum_Willys]

https://www.6mmbr.com/laddertest.html

Good review of shooting a ladder, and Optimum barrel time.

https://www.6mmbr.com/Quickload.html
Quickload tips

[Magnum_Willys]

Quickload is a program that you need to purchase correct?

Yes, but it won't tell you much until you accurately measure your fired case volume ( weight the water it holds) and accurately measure your average velocity from a couple fired rounds.  Then with this data and measurements of your cartridge and bullet you can start getting educated what-ifs as you change powder.  To develop an accurate load with it you must subscribe to the optimum barrel time theory that suggests your node is reached at a specific time the bullet is in the barrel based on barrel length.  Quickload gives you that time - adjust your load so the two times meet and viola ! Instant accuracy.   If only it worked so easy - but sometimes it does.   Usually if you are new to it you get a good load dialed in after a few hundred rounds because you get to be a better shooter by then - was it you or the load?   

[7mmfan]

Well i'm to the point that most of the time I'm convinced it's the load or the rifle because I can shoot exceptionally accurate groups in other rifles. This one rifle has me trying to think of ways to streamline my process for developing a load for it because thus far, I've had no luck.

[BULLBLASTER]

If it just won’t shoot try some other components, bullets or powder.

[7mmfan]

I've tried all kinds of components, thats the problem. Different bullet/powder combos, different primers, seating depths, etc... best I've gotten is 1.5" group. I'll admit though, I've bounced around a bit while trying those different things and I'm trying to streamline my system to make it easier to track and find good combos. What I read was guys using these OCW and OBT methods for finding node and load options. I just struggle with paying for the system. Probably worth it for my time in the long run though.

[Karl Blanchard]

It's really hard to give advice on hand loading because without seeing your process it's really hard to say one way or the other. One thing I will say is it's really hard to get sub moa accuracy out of a 1.5 minute rifle. Point being, all guns aren't accurate. Rifles are a dime a dozen. If it isn't up to standards sell it and get a different one. If you have shot that much and it's still not giving you positive feedback with changes then off that sucker.

As someone who has been guilty of this in the past, do not jump around! Its impossible to collect data when you aren't making calculated changes and adjustments

[buckfvr]

what rifle is it ?

[7mmfan]

It's really hard to give advice on hand loading because without seeing your process it's really hard to say one way or the other. One thing I will say is it's really hard to get sub moa accuracy out of a 1.5 minute rifle. Point being, all guns aren't accurate. Rifles are a dime a dozen. If it isn't up to standards sell it and get a different one. If you have shot that much and it's still not giving you positive feedback with changes then off that sucker.

As someone who has been guilty of this in the past, do not jump around! Its impossible to collect data when you aren't making calculated changes and adjustments

I'm not quite ready to give up on it yet, but I am trying to create a system so I stop jumping. I have other members involved holding me accountable.

It is a Remington Model 700 Mountain Rifle, 7mm-08. Not a cheap rifle.

[buckfvr]

So I am inclined to believe that normally, you would have better results from this rifle model, but since it seems to be a problem, I am throwing in with Karl and suggesting you off that sucker........ I dont think its you or what youre doing.

[BULLBLASTER]

I hear of people shooting a ladder and watching for velocity flat spots or different powder charges that group together well. I don’t think I’ve ever seen it. I will shoot a ladder over a chrono to find pressure and look for a good velocity range. Once I know that I’ll work with seating depth for accuracy.

This group was 10 rounds over a chrono, all of them different powder charges ranging from 2750 to 2950 FPS. Maybe if I shot much further I would notice shots grouping together but I don’t have a range where I can set paper past 200 yards. Also this rifle shoots everything (except nosler rdf) very well so I basically just worked for velocity.

[BULLBLASTER]

I’ll also agree with Karl and buckfvr. Some guns just don’t shoot like others. You can try things like bedding, or triggers etc to help it but that’s potentially pouring money into something that just isn’t going to work. Offloading it and getting something different may not be a bad option, or having it rebarrelled, or the option is always there to just get it shooting as well as you can and quit shooting groups with it. 1.5 moa would serve well as a hunting rifle for moderate ranges.

Does anyone know if there is any factory 7-08 ammo that just shoots well in lots of rifles? It might pay to try something like that to see what the gun is capable of?

[Karl Blanchard]

I hear of people shooting a ladder and watching for velocity flat spots or different powder charges that group together well. I don’t think I’ve ever seen it. I will shoot a ladder over a chrono to find pressure and look for a good velocity range. Once I know that I’ll work with seating depth for accuracy.

This group was 10 rounds over a chrono, all of them different powder charges ranging from 2750 to 2950 FPS. Maybe if I shot much further I would notice shots grouping together but I don’t have a range where I can set paper past 200 yards. Also this rifle shoots everything (except nosler rdf) very well so I basically just worked for velocity.

spot on. I run up to pressure, look for a flat spot then tune seating depth. If you have a full grain spot where you are only 15-20fps in difference your load is gonna be a bit more forgiving. If your rifles accuracy isn't getting better or reacting to changes with different adjustments it very well could be a rifle issue. Especially since it's a rem 700.

This was a 15 shot ladder test with a 300 win and n570. Not a ton of data so I started low. Not much to gain there besides chrono data which I feel is most important. One thing it does tell me is seating depth should be left alone.