Does “testing” repeat itself?

[Webster]

I have done testing of different primers and neck tension on multiple rifles. Every time there is a primer or specific neck tension that stands out more than others. Recently talking to a friend about this, he has some hesitation if a one day primer test is sufficient to say it’s better than others. We have all seen our rifles shoot good one day or evening, and be disappointed the next. I am sure at least one of you has tested primers or next tension on more than one occasion. Curious if they are a fixed variable once determined.

You didn't describe the rifle and the type of competition you shoot in. How small of groups can you shoot consistently at 100 yards? Is the driver variable bigger than the neck tension or primer variable? My self I wouldn't attempt to test neck tension or primers unless I could consistently shoot 100 yard groups very close to 0.250".

 

[rhovee]

Here is one of my examples. Did a quick 2 shot each for primer test at 300 yards. Yes it’s only 2 shots. But I feel like the results are clearer enough to not need further shots. I want to try this test again soon and see if I come to same conclusion.

 

[Orr89rocz]

Anyone ever do a neck tension change and experience a drastic change in point of impact?
My current rcbs die sizes the neck of my 300 wsm around .336” on my caliper. When seating a bullet it is very hard and sometimes the seater damages the bullet, like it dents the jacket. So i have been using OneShot lube on bullets to slide them in. It shoots good.
But yesterday I decided to try .337 bushing die and .338. Same charge same seat depth. Go to my 562 yard area to check dope for next weekend rifle season. Shot two regular tight neck rcbs die rounds at 562 yards and they hit low of bullseye About 5 inches With 2.8 mils dialed. So i was like ok, it needs More like 3-3.1 mils. Made correction and grabbed the .337 neck rounds. It hit 5” high of bulls. Hmm, dropped back down to 2.8 mils and hit bullseye with the .338 rounds. Groups were about the same so dont think either or shined.
So leave scope at 2.8 mils grap two more rcbs tight neck shells and they both grouped 5” low again.

did not check velocity of the .338 or .337 necks. But it would have to be substantially different to change poi like that imo

 

[AndyTaber]

Not saying anything wrong with doing some testing, but, no two pieces of brass are exactly the same, no two bullets, primers, or powder charges (whether weighed to the ..00001 or not). And then there is the wind. I don’t shoot at National matches but I do manage to hold my own when shooting with those that do.

 

[jelenko]

Another way of asking Andy's question is: What is the typical group size you get with with 10 shots at the 562 yard target?

 

[JFrank]

Here is one of my examples. Did a quick 2 shot each for primer test at 300 yards. Yes it’s only 2 shots. But I feel like the results are clearer enough to not need further shots. I want to try this test again soon and see if I come to same conclusion.

For me ( looking at your results) the BR-4 shoot consistently smaller so thats the one I would build around.

 

[taylorw]

Here is one of my examples. Did a quick 2 shot each for primer test at 300 yards. Yes it’s only 2 shots. But I feel like the results are clearer enough to not need further shots.

I like the 2 shots per charge weight when your bracketing + & - your node, when testing primers.
IMO, you can get a better idea of the forgiveness by testing this way over several range trips, in different conditions, as opposed to shooting 5+ shot groups in a single trip in the same conditions.
(Not trying to get off topic, but I feel that another primer that gets overlooked too often is Rem 7.5’s & 9.5’s. I will always add those into the mix as well)

Some days i think i myself as the shooter isnt as consistent as on another day and that may explain some of my groups lol.

I think your probably more consistent than you give yourself credit for.
I have found that if a particular rifle really likes a combo, It just seems very hard to mess up and will shoot small more times than not, regardless of the perceived negative input.

The opposite can be said for a bad load so I think that’s where, blaming for not being consistent, comes into play.

 

[INTJ]

An issue I see commonly is expectations on the accuracy of a certain rifle. My job is to find loads for customer rifles. These are almost always high end, bolt action, hunting rifles. Many guys seem to think if a $2000 factory rifle or a $3000 custom can occasionally shoot a 1/2" group, then their $6,000 rifle should shoot 1/4 MOA all day long. After all, that is what they see on the Internet.

Well, the barrel doesn't know if it's in a $2000 rifle or a $6000 rifle. All it knows is if the chamber was cut true and the barrel is decent quality.

The truth is that even if we get 1/4 MOA group on occasion with a hunting rifle, it will also on occasion shoot a 5/8 to 3/4 MOA group. Even when we get to incredibly accurate BR rifles we find dispersion. This would happen even if we were shooting a rail gun in a tunnel.

So we need to have realistic expectations when testing.

 

[BoydAllen]

If the wind is very switchy and hard to read, at 100 yards, I do not remember my PPC shooting in the .4s. In really good conditions, if I see a group in the high twos or low threes I start looking for the reason. This with very good conditions, and flags. I see very few flags at the range, very few, but people seriously think that they are doing valid testing. IMO there is a LOT more to it than a good barrel and chamber, a lot.

 

[INTJ]

Short range BR guys are obsessed with wind flags. And they do need them to shoot consistent .1s at 100 yds. However, flags aren't the only way to read wind, especially at longer distances. I shot four 1000 yd screamer groups last year with loads developed not using flags.

 

[BoydAllen]

Short range BR guys are obsessed with wind flags. And they do need them to shoot consistent .1s at 100 yds. However, flags aren't the only way to read wind, especially at longer distances. I shot four 1000 yd screamer groups last year with loads developed not using flags.

Those groups depended on the wind not changing. My point is that the only way that you know that it stayed the same was from looking at the targets. I have seen the results from matches where the conditions changed without warning, and excellent shooters were DQed because they were unlucky in what relay they were put on , and had no way to see the change. If you are testing components, the more variables you can eliminate the better. You want to know that all of the things that you were not testing, were the same for a particular test. When you are looking at small differences, and had no way to look at the wind, how do you know that the differences are not simply slight differences in the wind? To me, arguing that less information is better seems a bit illogical. While you cannot test a rifle for positive compensation at 100 yards, there is a lot that you can test for, with greater certainty about what you are shooting through.

 

[INTJ]

Those groups depended on the wind not changing. My point is that the only way that you know that it stayed the same was from looking at the targets. I have seen the results from matches where the conditions changed without warning, and excellent shooters were DQed because they were unlucky in what relay they were put on , and had no way to see the change. If you are testing components, the more variables you can eliminate the better. You want to know that all of the things that you were not testing, were the same for a particular test. When you are looking at small differences, and had no way to look at the wind, how do you know that the differences are not simply slight differences in the wind? To me, arguing that less information is better seems a bit illogical. While you cannot test a rifle for positive compensation at 100 yards, there is a lot that you can test for, with greater certainty about what you are shooting through.

There was certainly wind in attendance. The way we shoot tuning ladders does a bunch to eliminate the effects of wind when tuning at long range. Crud, the way we shoot in competition does a lot to minimize wind issues.....but we do use flags at matches, though mirage is probably a better indicator.

My point is simply that you don't need wind flags every 10 yds to be able to find good loads and test things at 100, or 200, or 300 yds unless you are tuning a short range BR rifle.

Where I agree is that testing should account for as many variables as possible, and wind indicators are part of that process. At my local range--which goes to 400 yds, there are evergreen trees on either side of the relative narrow shooting lane as well as vegetation along a creek that runs across at about 35 yds. It's easy to read the wind there without putting out additional flags.

 

[JFrank]

If a condition changes enough to DQ you should Damn sure see that without a flag.

 

[LRPV]

If a condition changes enough to DQ you should Damn sure see that without a flag.

I know about 10 guys who did NOT see it in Montana last August...

 

[JFrank]

I know about 10 guys who did NOT see it in Montana last August...

Jason, I was one of them on that firing line and still kicking myself for not waiting it out. I could clearly see the trees moving all over the place.

 

[BoydAllen]

My point is that lots of things do not have to be tested at 1K and for those things putting out a few flags is a good idea. As far as putting them out every ten yards goes, evidently someone has never been to a short range match. Typically at 100, it would be four, and at 200 five or six, for a match. For testing I often use two, one at about fifteen and another at fifty. I know that that is a bit sloppy, but I seem to be able to do some good work that way. For guys who are on a budget, a couple of sticks that go up to the height of the bullet path (if possible) with surveyors tape tied to the top, hanging down to just above the ground are inexpensive, and a LOT better than nothing. On DQing, I wrote up the nationals when they were shot at White Horse, and interviewed the winner, who shot a .300 WSM for both LG and HG. Before the match I reviewed a topo. map of the range area, and took a look at the weather history, and reviewed conditions of the match. A friend was in the pits during a big switch at Deep Creek when there was a big change. If you had just started your record when it hit.... I have also looked at the difference between different relays for several matches.

 

[JFrank]

When testing at 500 yards i use one flag at about 150 yards, at 1 k we use round robin ladders with whenever you can see for mirage or wind. At DC you have to pick your poison and decide when NOT to shoot and that may be part of the revolving door in the winners circle along with who's got the tune that day.

 

[INTJ]

My point is that lots of things do not have to be tested at 1K and for those things putting out a few flags is a good idea. As far as putting them out every ten yards goes, evidently someone has never been to a short range match. Typically at 100, it would be four, and at 200 five or six, for a match. For testing I often use two, one at about fifteen and another at fifty. I know that that is a bit sloppy, but I seem to be able to do some good work that way. For guys who are on a budget, a couple of sticks that go up to the height of the bullet path (if possible) with surveyors tape tied to the top, hanging down to just above the ground are inexpensive, and a LOT better than nothing. On DQing, I wrote up the nationals when they were shot at White Horse, and interviewed the winner, who shot a .300 WSM for both LG and HG. Before the match I reviewed a topo. map of the range area, and took a look at the weather history, and reviewed conditions of the match. A friend was in the pits during a big switch at Deep Creek when there was a big change. If you had just started your record when it hit.... I have also looked at the difference between different relays for several matches.

The one short range match I watched was around 15 years ago at Ben Avery, and there were considerably more than four flags to 100 yds. And I agree that not everything needs to be tested at long range competition distance. though the more testing at long range the better.

My point is simply that wind flags aren't the only tool to read wind. And yes, I have been led astray by wind flags.......

 

[BoydAllen]

The one short range match I watched was around 15 years ago at Ben Avery, and there were considerably more than four flags to 100 yds. And I agree that not everything needs to be tested at long range competition distance. though the more testing at long range the better.

My point is simply that wind flags aren't the only tool to read wind. And yes, I have been led astray by wind flags.......

I think that we have all had to resort to other methods at one tie or another. I watch grass,and foliage, listen to the resonance in my ear muffs and what it feels like on the back of my neck, but at a range, my flags are my go to.