Range Report How do you evaluate your range results?

[Deadman Pointers]

This probably should go into the stupid marksmanship questions category, but how do you evaluate your range results when testing out new loads if you don't do a ladder test?

I ask because I'm sure I was the cause for some of the variation since I was forced to shoot off a bench at a public range... you know, the ol' just can't get situated excuse. I mean, can someone who has evaluated enough targets reasonably discern user problem from shot variation due to the rifle/load?

Anyone care to weigh in on how you'd read these tea leaves? You won't hurt my feelings. These are from a 300WM shooting a 215 Berger Hybrid.

 

[Iwillylike2shoot]

I'm interested to see how this turns out.

 

[STI_1911_Guy]

Get a magneto chronograph. Running your loads through a chrono will give you a relatively repeatable and consistent variable to "judge" your range trip from, group size alone is to easily affected. If you shoot great groups at 100 yds but the ES and SD are way off then you know the loads not right. If you feel like you didnt have the greatest rest or shooting technique or just an off day but the SD and ES #'s are good then you might still have something. Part of my living is from gunsmithing and I offer load development for anybody that wants it and I document all of findings and I can tell you that 95% of the time the node with the best SD and ES is all you need to go by. Set the bullet .020" off the lands and begin running through the chrono. I see to many people burning through 20% of their barrel life chasing the perfect load and adjusting every variable possible trying to squeak out that last .1" when its already shooting .4-.6" consistently. This is just my opinion from the data I have collected.

 

[Deadman Pointers]

Get a magneto chronograph. Running your loads through a chrono will give you a relatively repeatable and consistent variable to "judge" your range trip from, group size alone is to easily affected. If you shoot great groups at 100 yds but the ES and SD are way off then you know the loads not right.

Take a look at the groupings I posted earlier; the SD and average velocities from my magnetospeed are included with the spread analysis. The tightest grouping has a SD of 6. The best SD of 2 had one of the higher spreads. This is why I'm asking if you can see perhaps a pulled shot on an otherwise ideal grouping or if you can see that the load is not right because of the shot pattern.

I'd appreciate your input on these specific groups.

 

[Milo 2.5]

This probably should go into the stupid marksmanship questions category, but how do you evaluate your range results when testing out new loads if you don't do a ladder test?

I ask because I'm sure I was the cause for some of the variation since I was forced to shoot off a bench at a public range... you know, the ol' just can't get situated excuse.

First, if it was uncomfortable shooting, you probably knew results will be inconclusive before you fired. Why don't you reshoot the test? Get where you want to be, results may be completely different.
I did close to the exact thing this spring, finding factory ammo in a 243, I was so out of place, I was shooting 5 or 6 shots and counting results from the best 3, I made it work, got out at a different spot, and my choices were good, but my grouping that day looked like an unwiped ass.

 

[culater]

Take a look at the groupings I posted earlier; the SD and average velocities from my magnetospeed are included with the spread analysis. The tightest grouping has a SD of 6. The best SD of 2 had one of the higher spreads. This is why I'm asking if you can see perhaps a pulled shot on an otherwise ideal grouping or if you can see that the load is not right because of the shot pattern.

I'd appreciate your input on these specific groups.

I would take group out at distance at 500 yds and come back with a report. All I worry about is vertical spread at long range now. That what I learned from reading from the 1000 yds bench rest guys. I would go with your tightest group and go have fun. The best advice is to record the speed node. Then buy all the powder in 8lb kegs you need to keep everything consist. When you move to a new 8lb you just use your magneto speed to find the speed node you recorded then resume having fun shooting. If your holding sub moa vertical your doing well. Just need to learn to read the wind at distance.

 

[Deadman Pointers]

May sound like a remedial question, but can someone with much more experience than me identify vertical dispersion caused by something other than velocity differences? In the groupings above, the one with the most vertical dispersion had the lowest SD of 2.4 while the one with the least had the highest SD of 11.4. One could reasonably suggest that some 'other' factor(s) contributed to the variation in the low SD group, and it should be the most accurate loading.

I certainly plan to take these out to distance; my hope was that there was some logic or methodology that would support me pursuing one load versus another due to some time constraints.

Thanks for all the replies so far.

 

[theLBC]

vertical strings can be caused by poor breathing control or something related to your position or hold.

 

[spife7980]

May sound like a remedial question, but can someone with much more experience than me identify vertical dispersion caused by something other than velocity differences?

Yeah, it could be from trying to shoot groups with the magneato speed strapped on.

Its hard to get good test results if you dont do a good test to start with.

 

[BruntBronze]

I use muzzle velocity to estimate pressure, SD, then ctc, then ctc without magnaspeed, then back to SD.

I don't do ladder tests as I'm too much a variable in shooting.

 

[pmclaine]

Shoot a two inch circle at 200 yards, ten rounds, all ten should be in or break the line of the circle, anything out you would probably call it.

Shoot a three inch circle at 300 yards, Id be happy with 7 or 8 of 10 in the circle and the misses were called or just out.

I dont have any more range than 300 yards so thats my opinion if you are just considering a subjective results test.

Your data seems tight but what matters is what it does through the rifle.

Now I must actually try this test someday.

 

[8up]

To be honest Deadman, based on the 3 target groupings I see by eye, you have a good load for the rifle. No crazy fliers, each shot in all the groups are almost all touching even though they are spread out in different directions.

It is either one area in your fundamentals are off somewhere, your position to drive the rifle is off, or recoil management. Possible additional thought, is parallax adjusted out? Focus on reticle crosshair while making the shot, the reticle is your front sight.

 

[skatz11]

Try shooting 10rd groups the results might surprise you. I’ve found that if I’m not shooting rifle a lot, or completely in the zone 5rd groups can be difficult to interpret. Any lapse in the fundamentals will show up and it’s not always easy to self diagnose.

Also if you pair this with a chrono you have more data points for ES and SD.