Finding good "node"

[Magnum_Willys]

I can shoot 1” groups at 100 yards and 1.5” at 300.    Few people see smaller actual groups at distance but its common to see smaller moa at 300 vs 100 with long bullets that do take a bit to stabilize.  You wont see this with standard bullets just the 300 grainers or maybe long 230’s. 

[Cheif]

I can shoot 1” groups at 100 yards and 1.5” at 300.    Few people see smaller actual groups at distance but its common to see smaller moa at 300 vs 100 with long bullets that do take a bit to stabilize.  You wont see this with standard bullets just the 300 grainers or maybe long 230’s.

Oh you've done it now!!! Haven't you heard of physics??  Yes, you are correct, thank you

[Jonathan_S]

How do bullets hone in to center after they stabilize downrange?

[BULLBLASTER]

I can shoot 1” groups at 100 yards and 1.5” at 300.    Few people see smaller actual groups at distance but its common to see smaller moa at 300 vs 100 with long bullets that do take a bit to stabilize.  You wont see this with standard bullets just the 300 grainers or maybe long 230’s.

The “I can shoot” is the important part there. It is not that the gun is more accurate at longer distance it is that you, the shooter are doing something different. Maybe you concentrate better at longer distance? Or parallax is less? Something like that. If you could set up a target at 100 and shoot through that target to one at 300 I can assure you that the group printed on the 300 yard paper will not be a smaller angular dispersion than that of the 100 yard target. There is just no way that a bullet knows where it needs to “settle” in to. Once that bullet leaves the muzzle it is set in that direction until an outside force affects it.

[Cheif]

What's the answer then? Faster twist?

[Magnum_Willys]

It may be positive compensation, stabilization, parallax or just a finer crosshairs at distance but regardless I find load development at 300 yards to be more applicable to long distance load development than shooting at 100 yards.    I’ve had loads that one-hole at 100 that were much worse at 1000 than loads that were not as good at 100.   

[Cheif]

Truth willys...

[BULLBLASTER]

I won’t disagree that testing loads at a greater distance is better. I’ve seen some very small 100 yard groups that wouldn’t shoot for crap at further distances. Take the group i posted earlier in this thread for example. Almost 200 FPS velocity spread still grouped sub moa at 100.
I just don’t buy that a further target can consistently have a smaller angular group for the same shots fired.

[Cheif]

Triple digit spread??? Wow

[Cheif]

200 fps at that??? Good god!!! What powder???

[BULLBLASTER]

200 fps at that??? Good god!!! What powder???

It was a ladder working up from fireforming to full load in an Ackley improved chambering. Using h4895 the last time I chronod my finished load I had an es of 12 over w
10 rounds

[jasnt]

I’ve heard many different people talk about better grouping at 2-300 that one hundred. Brian litz talks about this in his book. Yaw typically from bullets not be spun fast enough at the muzzle but rpm speed degrades slower than velocity.  Never seen it my self as I always go with “too fast of twist”.

When I start load development I start with seating depth and a low charge.  Load in increments from mag length or .015” off in .030” steps
Choose the best one and shoot over the chrono and find the velocity flat spots.  Fine tune seating depth in .005” increments if I’m not happy already.   

Maybe I’ve been lucky but I’ve never not found a 1/2 moa load in any rifle I’ve loaded for except for the rifles that I had burned out the barrel. 

Some folks have warned me going too fast twist can blow up bullets but I have yet to see it my self.  Recently I worked up a load in my 7 twist 243 and 62gr Berger target bullets at 3960.   They shoot great even at 735 yards.   Also played with a few 58gr vmax at over 4K and they hit the 400 no problem.   

Jme

[wooltie]

I had a m70, stock barrel that wouldn't group less than 1.5"  Even sent the gun to winnie to have the barrel evaluated.  They evaluated and lapped the barrel, sent it back to me.  No change in performance.

I swapped the barrel for a benchmark.

Kept everything the same - rifle stock, bullets, powder, shooting rests -- and the gun shoots moa or better now.

FYI I use Jason's method to find a load.  Works great.

[TheArmoredShop]

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?

I do. It’s a lot of fun too.

I set a 6’x4’ target up at 800 yards. I use an OAL gauge to measure where my throat in my gun is at, and then start with a .010” jump.

I load 3 bullets, starting 10% off max book load. Going up 1% each three shots.

After each three I write down the number of the group next to it. I do this until I reach 100% of book max or I’ll keep going if I’m showing no distress in casing or primers. I went to 105% in my 300 winmag with h1000. Was like 84 grains of powder with 212 eld-x. Compressed for sure and a shoulder whopper. Was getting almost 3300FPS off the Labradar.

[TheArmoredShop]

One you find the flat spot, you’ve found a node. If you like the velocities of that group, work with that powder charge.

The only thing you will mess with from there is jam or jump. I got as far as .005” jam and down to .025” jump. (This is referring to the distance of the ogive to the lands).

You will shoot groups of 3 every .003” inch each way. This is at 100 yards.

I’d still use chrono (in my case a labradar) to check deviation and spread.

I now have a load developed for my 300 WM with 212 ELDX that delivers 1000ftlbs of energy well over 1000 yards. With my Nightforce, I check my dope chart on my gun, turn the turret and send one flying knowing I’m sub MOA at ANY distance if wind is read right.