Opinions needed for a grouping test

[Lee308]

Hiyas,
I have been working up some loads using Nosler custom comp projectiles. Today I went out and shot 6 groups and although it was a little windy I didn't think it would affect the sideways drift this much at 100 yards. The wind was gusting at about 10 to 15 mph from the left at about 10 o'clock. Could the sideways drift be a function of the load or is it just the wind and my lack of ability to hold the rifle still. Although I have measured the groups for the elevation deviation I would like to hear anyone's opinion on which group they think is the best just to either confirm or make me rethink my thoughts.
Thanks

 

[Jeff A]

I personally feel it would be a waste of time and resources to test loads in those conditions.

 

[Erik Cortina]

I personally feel it would be a waste of time and resources to test loads in those conditions.

Not true!

I just don't think you really hit on a good accuracy node. You should first start by loading with 0.5 gr. increments until you see pressure signs. You only need 3 shot groups for this test. You will see where the accuracy node is and then you can do the test over with smaller increments in powder charge, maybe 0.2 gr. that cover the whole accuracy node. After you find the best load, then test seating depth to get optimum accuracy.

Working up loads in calm conditions is a waste of time unless you are trying to diagnose gun problems or shooting technique issues. But if you are planning to only shoot your gun in competition or in general when conditions are perfect, then work up loads in perfect conditions! ;D

 

[necchi]

10-15 w/gusts will easily move a a 30 cal bullet @2800fps 1, 1 1/2"s at 100.
( it's the gusts that mess with ya esp during load development )

But when I see horizontal lines like 45.6-45.7 and 46 with MY targets, it's me on the trigger. Honest, I had to learn better trigger control to stop the horizontal stuff, and it still gets me at times. Vertical spreads are loads that missed the good node.

It's a tuff call, I'd re-test the loads I mentioned. The biggest deal is learning to be honset with yourself with load development. If you pulled the shot, YOU know it, , then call it as such.
No shooting is a waste of time, you learn at every session if you allow yourself too.

 

[artbosco]

I have been working up some loads using Nosler custom comp projectiles. Today I went out and shot 6 groups and although it was a little windy I didn't think it would affect the sideways drift this much at 100 yards. The wind was gusting at about 10 to 15 mph from the left at about 10 o'clock. Could the sideways drift be a function of the load or is it just the wind and my lack of ability to hold the rifle still. Although I have measured the groups for the elevation deviation I would like to hear anyone's opinion on which group they think is the best just to either confirm or make me rethink my thoughts.

First, there's nothing wrong with testing in those conditions. The Legend of Benchrest, Tony Boyer, recommends it in his new book, The Book of Rifle Accuracy, on page 261, When to Tune or Practice, in Chapter 22, Tuning Your Rifle.

One group, for each load, isn't going to tell you a thing. You're going to need multiple groups for each load, before you start to see any pattern develop. I recommend you purchase a copy of Mr. Boyer's book and spend some time in Chapter 22. Here's one source: http://www.brunoshooters.com/Merchant2/merchant.mv?Screen=PROD&Store_Code=BSS&Product_Code=TBSC .

Moreover, when you shoot your test groups, use a very stable front and rear rest that will impart at least some sense of consistency from shot to shot and group to group. Wind flags will help with picking a condition that will stay around long enough to finish a group.

Don't forget, loads, neck tension, and seating depth, all contribute to the fine tuning process.

 

[4xforfun]

10-15 w/gusts will easily move a a 30 cal bullet @2800fps 1, 1 1/2"s at 100.
( it's the gusts that mess with ya esp during load development )

But when I see horizontal lines like 45.6-45.7 and 46 with MY targets, it's me on the trigger. Honest, I had to learn better trigger control to stop the horizontal stuff, and it still gets me at times. Vertical spreads are loads that missed the good node.

It's a tuff call, I'd re-test the loads I mentioned. The biggest deal is learning to be honset with yourself with load development. If you pulled the shot, YOU know it, , then call it as such.
No shooting is a waste of time, you learn at every session if you allow yourself too.

So, if that is the case, should I shoot all of my load developmet 5 shot strings in 10 seconds, and my 10 shot strings in 20 seconds? That is the way I do it in competition.

 

[6BRinNZ]

I personally feel it would be a waste of time and resources to test loads in those conditions.

Not true!

Working up loads in calm conditions is a waste of time unless you are trying to diagnose gun problems or shooting technique issues. But if you are planning to only shoot your gun in competition or in general when conditions are perfect, then work up loads in perfect conditions! ;D

hey Erik, I don't understand this from a load development point of view. To me it just makes the equation simpler to not be developing a load in the wind (I know wind always exists...I am talking relative to the posters conditions). Isn't the accuracy node for the barrel the same for calm or windy conditions? I appreciate that Boyer and the likes could say one barrel is better than another in the wind...I guess I have always figured there is only a certain echalon of shooters that could deduce that accurately.

I have always had the train of thought that once I have my load I then need to put it through its paces in various conditions, not to see if I can improve it but to see what it will do...the thought being the node is the node be it 1mph or 20mph winds.

...Not arguing just interested in your view point and reasoning (PM me if you want). I do have access to Tony Boyers book...maybe I should go read

 

[Heavies]

I see a pattern in those groups. Seems to me they spread out, tighten up, then spread out again. I'd mess around with 45.7-45.9

IMHO work on tweeking in those areas, if there is no pressure signs.

 

[rayjay]

There is no bigger waste of time and money than working up loads without windflags of some sort. Also, when conditions get bad enough it's a waste of t&m even if you have windflags. The better the conditions the better idea you can get of how the gun, load and shooter are doing. Once you get a good load and your bench technique gives consistent results THEN you start learning to shoot in the wind.

There is an article on the homepage in which the author says that some long range shooters don't worry about the horizontal when load developing. They only measure the vertical. At longer ranges though there is the effect of the rifling twist that does add vertical in a cross wind. This effect is very pronounced on a rimfire.

 

[Erik Cortina]

[QUOTE author=6BRinNZ]
Isn't the accuracy node for the barrel the same for calm or windy conditions?
[/QUOTE]

No.

 

[necchi]

[QUOTE author=6BRinNZ]
Isn't the accuracy node for the barrel the same for calm or windy conditions?

No.
[/quote]

Ok, I'm curious,,Why not?
How can the best accuracy from the barrel and load change with weather conditions?

 

[Erik Cortina]

[QUOTE author=6BRinNZ]
Isn't the accuracy node for the barrel the same for calm or windy conditions?

No.

Ok, I'm curious,,Why not?
How can the best accuracy from the barrel and load change with weather conditions?
[/quote]

Because sometimes the gun will shoot bullets straight that are not completely stable, therefore they will group good in calm conditions but will be very wind sensitive, therefore shooting big groups in windy conditions.

 

[BoydAllen]

So that we can better understand what you are doing, tell us about your rifle, rest, and if you are shooting over flags. I find that it is common for shooters to have issues other than their loads, that interfere with their testing to such a great degree that changes need to be made before any meaningful testing can be done. Two more questions, trigger pull, and seating depth? As to the distinction between best tune for no wind, and some wind being different, I would suggest that at your current level of accuracy (no disrespect intended) you have bigger fish to fry.

 

[6BRinNZ]

[QUOTE author=6BRinNZ]
Isn't the accuracy node for the barrel the same for calm or windy conditions?

No.

Ok, I'm curious,,Why not?
How can the best accuracy from the barrel and load change with weather conditions?

Because sometimes the gun will shoot bullets straight that are not completely stable, therefore they will group good in calm conditions but will be very wind sensitive, therefore shooting big groups in windy conditions.
[/quote]

ahh - makes sense, thanks....damn, now I have a whole bunch more questions

 

[Lee308]

Hiyas,
Sorry I didn't get back to this earlier had a few dramas with the connection.
Allan, I have lots of issues. ;D but yes I understand where your coming from. The rifle is a model 12 savage with a 34' 1:10 match barrel fitted with a tuner, firing of a Caldwell rear bag (soon to be an Edgewood Mini Gater when it arrives here in Aust from your side of the globe :) and using a f-class style rest for the front. I normally use Dyer HBC projectiles with pretty reasonable results. Having run out and unable to get more straight away due to circumstances, I thought I would try 155g noslers custom comp projectiles as I had a box of them kicking around and have never used them before in this rifle. I have a long range meet coming up and thought I would try and work up a load so I could use them at the upcoming meet. Given the match will be shot from 1000 yrds I started working up the load midway through the suggested loads laid out in the reloading manual I was using, to get the velocity I need to get to 1000 comfortably. Normally yes, I shoot with flags at the range and in comps however, where I shot the load test dose not have flags and given the wind I expected some side ways drift just not that much was all. My trigger control isn't perfect and is an ongoing practice, therefore I know some of the shots were just me (generally the shots that are low and to the right). The original seating depth was .050 and that wasn't any good so on advice from a friend I reduced it to .020 from the lands and that was a little better. Basically all I was trying to do was to find the tightest group from a load, before tweaking it with the tuner and playing around with seating depth.
I know from past tests that myself and the rifle are capable of .25', 3 shot groups @ 100yrds. Doing it all the time? not so much.( A bad day maybe?)
I have reloaded the loads of 45.6 ,7, 9 and 46 as the were no signs of pressure and will be testing them again only this time over a crono and early in the morning before the wind gets up.
Erik, you may be right about missing the accuracy node considering I started half way up the load range. Given the fact that I have a tuner is it possible to adjust the tuner for this or would the tuner not have enough effect. It may be a case of starting from the bottom and working up and losing a bit of the velocity.
Thanks for all the replies, links and advice The book of Rifle Accuracy sounds like a good one for the collection.
I'll get back with results from the retest.

 

[BoydAllen]

I have generally gotten my best groups with bullets seated to engage the rifling. If your bullets have a tangent ogive, I would start at a point where the rifling marks are about half as long as wide. (It's a short range BR sort of reference.) Of course you should drop back and work up on your powder charge. When I do a load workup, I pick a seating depth, based on my experience with similar ogive shapes, and do a sort of ladder test, at 100 yd. In your case, I think that I would do my initial work with jumps of about .4 grain. I shoot one shot per powder charge, on a day when the wind is cooperative, over flags (3-4), and shoot all my shots on a single target, plotting bullet holes as I go. When I get to the point where a FL sized case gives a little more resistance on extraction than I would like, I stop, note the load, temperature, and humidity, and examine the target for any clusters. These would indicate good places to continue investigation, by small variations (.003) in seating depth. Getting back to flags, I never depend on the range, I bring my own. In the past, they may have been as basic as sticks with plastic surveyors' tape of the same length tied and taped to their tops. Good luck.

 

[rayjay]

The new rear bag will make a heck of an improvement. You can use your old bag on your workbench when working on rifles.

Lee, lets say that you are shooting at 100 yds with no flags. Now if you had flags they might show you that some of your shots where shot in a slight left wind but that other shots where fired in a slight right wind. If you had shot all your shots in one condition you might have had a .2 or .3 but since you shot in a 'reverse' you now have a .5 or .6. Heck, who knows, there might have been a gust and now you have a .7 or .8. Since you don't have flags you are thinking 'Damn I suck' or 'Damn my rifle sucks' or 'Damn my reloads suck' or 'Damn I need to change my powder by .1 gr'. Rayjay would be sitting beside you thinking 'Damn dude needs some flags'.

Move all this out to 200 yds are more and the possibilities for the wind to mess with you are increased way beyond what happens at 100 yds. At my range the flag at 85 yards might be showing a3 to 5 mph wind while the flag at 125 yds will be showing 15 mph. At the same time the flag at 15 yds would be showing maybe 1 mph or less.

 

[Lee308]

I have generally gotten my best groups with bullets seated to engage the rifling. If your bullets have a tangent ogive, I would start at a point where the rifling marks are about half as long as wide. (It's a short range BR sort of reference.) Of course you should drop back and work up on your powder charge. When I do a load workup, I pick a seating depth, based on my experience with similar ogive shapes, and do a sort of ladder test, at 100 yd. In your case, I think that I would do my initial work with jumps of about .4 grain. I shoot one shot per powder charge, on a day when the wind is cooperative, over flags (3-4), and shoot all my shots on a single target, plotting bullet holes as I go. When I get to the point where a FL sized case gives a little more resistance on extraction than I would like, I stop, note the load, temperature, and humidity, and examine the target for any clusters. These would indicate good places to continue investigation, by small variations (.003) in seating depth. Getting back to flags, I never depend on the range, I bring my own. In the past, they may have been as basic as sticks with plastic surveyors' tape of the same length tied and taped to their tops. Good luck.

Thanks for that mate. As this load developing thing is still relatively new to me, this info is very well received. After thinking about how much emphasis was placed on the size of the jump in relation to accuracy by the persons who responded to the post, today I dropped in to my local gun shop and picked up a seating die with micrometer to make life a little easier. As I learn more about reloading it seems length of jump is something I will be playing with a lot more.

Rayjay,
Flags are in the making(got hold of a sheet from the closet ;D shhh!) and making some up tonight for the big test day on Friday. I will be making up 4 in number, one for every 50 yards and setting a second target at 200yrds. the only problem with extending the range is I have to change the direction in which I shoot, doing this means I don't shoot into a hill so I had to arrange a few 44gln drums and will be filling them with sand and rock when in place so unfortunately that wont be done before Fridays test. A few weeks away at the most though.

Damn I have soooooo much to learn about this load testing stuff

Thanks again for the feed back guys. I has all been taken in and will be very useful.

 

[rayjay]

See if you can acquire a roll of surveyor's ribbon for you initial foray into windflags. In the beginning just shoot when the ribbons are all on the same side. It's also enlightening to shoot a few shots when the ribbons switch over 180 degrees.

 

[Lee308]

Hiyas,
I finally managed to get a nice day and the time to get the group test done and the results were a lot better.still a bit of tweaking to do but a lot better than the first attempt. Thanks for all the advice and tips. The pic is a group of four, shot at 100yrds using 155g Nosler custom competition projectiles and a load 0f 45.7g of AR2208(Varget). Using the surveyors tape as wind flags was a great help. For those not familiar with Aust currency our Five Cent piece is roughly the size of the US Dime.
Again thanks for all the advice.
Cheers