help me make sense of this?

[Randy Bohannon]

A ladder test is useful when one can’t be bothered to work up the conventional way, I think ‘medic already has and therefore it would be pointless; especially as trusting one round to show over pressure is not a very good idea.

the node seems a grain apart from his data, he absolutely needs a chronograph if he is going to explore.

[Army-medic]

A ladder test is useful when one can’t be bothered to work up the conventional way, I think ‘medic already has and therefore it would be pointless; especially as trusting one round to show over pressure is not a very good idea.

the node seems a grain apart from his data, he absolutely needs a chronograph if he is going to explore.

Yes, I think I have passed the stage of ladder testing as the original loads were a result of an OCW test. Though admittedly to a maximum as stated by Viht. Which may be a little conservative in reality.

[Randy Bohannon]

Yes, I think I have passed the stage of ladder testing as the original loads were a result of an OCW test. Though admittedly to a maximum as stated by Viht. Which may be a little conservative in reality.

Would you like to borrow a chronograph, I’m not too far from you?

[bullbarrel]

Anything with an ES less than 25fps is very good.

I don't see whats wrong with either of these loads, if they are repeatable.

Series 1 Shots: 5
Min 2750 Max 2772
Avg 2765 S-D 8.8
ES 22

Series Shot Speed
1 1 2767 ft/s
1 2 2750 ft/s Group Size: 0.47 MOA
1 3 2770 ft/s
1 4 2772 ft/s
1 5 2769 ft/s
---- ---- ---- ----


Series 2 Shots: 5
Min 2757 Max 2775
Avg 2768 S-D 7.4
ES 18

Series Shot Speed
2 1 2775 ft/s
2 2 2773 ft/s
2 3 2766 ft/s Group size 0.44 MOA
2 4 2757 ft/s
2 5 2773 ft/s
---- ---- ---- ----

Whats wrong with a rifle grouping <1/2 MOA

[Army-medic]

Anything with an ES less than 25fps is very good.

I don't see whats wrong with either of these loads, if they are repeatable.



Whats wrong with a rifle grouping <1/2 MOA

With factory ammo the groups were a single ragged hole.

[Army-medic]

Would you like to borrow a chronograph, I’m not too far from you?

Thanks for the offer but they published velocities were from my own magnetospeed v3, so I already have one.

[Randy Bohannon]

Thanks for the offer but they published velocities were from my own magnetospeed v3, so I already have one.

Aha!

were you shooting for group at the same time as shooting for velocity?

[Army-medic]

Aha!

were you shooting for group at the same time as shooting for velocity?

Yes. Do you think the chrono affected harmonics ? It’s only just occurred to me.

[bullbarrel]

Yes. Do you think the chrono affected harmonics ? It’s only just occurred to me.

If its attached to the barrel then will have some. But if it was that bad I'm sure there would be warnings about it.

[Randy Bohannon]

Yes. Do you think the chrono affected harmonics ? It’s only just occurred to me.

Anything hanging off the barrel will affect the harmonics, for better or worse.

several companies make barrel tuners which screw in and out to “tune” group sizes.

i tried a magnetospeed and found it made groups open up on two of my rifles.

given that introducing unquantifiable variables is an anathema to good reloading practice, I err on the side of caution and use a conventional chrono.

did you shoot the factory ammo with the magnetospeed on the harrel?

[Parabuteo]

A ladder test is useful when one can’t be bothered to work up the conventional way, I think ‘medic already has and therefore it would be pointless; especially as trusting one round to show over pressure is not a very good idea.

the node seems a grain apart from his data, he absolutely needs a chronograph if he is going to explore.

Never used one when I shot FTR but trusted the results and the rifle. My ES was 6FPS (finally measured by 2 different magnetospeed chronos) and yes, if you attach anything to or touch a free floating barrel with anything, it will affect the harmonics. How do we thing barrel tuners work?

With high performance rifles anything you can do that reduces the time between changes is a bonus. Dont sweat the stats, they will as likley be different between days and groups. Just get out there real time and see how they perform on paper, thinking about the marksmanship principles and consistancy. And work from there.

[Randy Bohannon]

Never used one when I shot FTR but trusted the results and the rifle. My ES was 6FPS (finally measured by 2 different magnetospeed chronos) and yes, if you attach anything to or touch a free floating barrel with anything, it will affect the harmonics. How do we thing barrel tuners work?

With high performance rifles anything you can do that reduces the time between changes is a bonus. Dont sweat the stats, they will as likley be different between days and groups. Just get out there real time and see how they perform on paper, thinking about the marksmanship principles and consistancy. And work from there.

Your load worked because it had a single digit ES and grouped well, a chronograph will tell you that faster than a season’s FTR shooting, surely?

[Parabuteo]

Your load worked because it had a single digit ES and grouped well, a chronograph will tell you that faster than a season’s FTR shooting, surely?

It did not take a season. Nothing like. It was league FTR. Experience told me how to carry out the load dev, the chrono was pure chance when the MS came out, I tried a pair to make sure the first was not showing silly figures. Oddly I had a lot of other loads that worked too....I still do....without a chrono.

The point is that people get tied up in apps, chronos, electronic targets, and usually end up going back to shooting at good old paper and either being happy with the results, or not.

My only use for a chrono has been to determine whether a rifle was over the HME limit, or to get some basic data for developing wind charts. Tried a Labradar for this purpose a while back, heap!!!

Obviously sometimes you will get issues, but often too much data fudges the picture. The next time the OP works up a load it will take less time, etc etc.

[Randy Bohannon]

It did not take a season. Nothing like. It was league FTR. Experience told me how to carry out the load dev, the chrono was pure chance when the MS came out, I tried a pair to make sure the first was not showing silly figures. Oddly I had a lot of other loads that worked too....I still do....without a chrono.

The point is that people get tied up in apps, chronos, electronic targets, and usually end up going back to shooting at good old paper and either being happy with the results, or not.

My only use for a chrono has been to determine whether a rifle was over the HME limit, or to get some basic data for developing wind charts. Tried a Labradar for this purpose a while back, heap!!!

Obviously sometimes you will get issues, but often too much data fudges the picture. The next time the OP works up a load it will take less time, etc etc.

Well yes as a folksey general point shooting at paper is the acid test but not having a chrono isn't why your load turned out to have single digit ES.

This chap is trying to find out if his load would work at the distance required.

A chronograph tells him that without having to shoot at that distance.

More importantly he is contemplating going above the max load in the manual.

A chronograph is the next best thing to a pressure lab in these circumstances.

[Parabuteo]

A chronograph is the next best thing to a pressure lab in these circumstances.

Really. The standard pressure signs are to be ignored then? And what distance? I shot my tests at 200.

EVEN IF I had worked the load up with a chrono it would have meant nothing other than at 3200 FPS with a 155gr bullet I was over the 3105 HME limit.

It would not have shown hard extractions, case head expansion (you can measure that with shooting shed's excellent gauges) bolth thrust signs, primer flattening, or accounted for temp senistivity or the ammo. With some brass (such as the .308 Lapua Palma) you will not see most of the usual pressure signs unless they are severe. Bolt thrust marks and head measurment is a good indicator.

It would not have known that for litigation reasons many load limits are over safe (but I do not suggest they are ever ignored), that the Lilja 3 groove barrel was designed for higher velocity and produced them with loads that would produce a lower velocity in barrels of the same length with more grooves. It would also have no idea about what powder was being used, COAL, compressed or not (which can often produce more consistant ES but with no real gain in velocity).

In fact, it was the use of the chrono that stopped me using a match winning load and down loading to the detriment of my results. The particular bullet needed to be pushed (Berger Hybrid 155), only later when speaking to a chap from Lilja did I realise the various factors that showed such good results were manifold and safe, but at least I then knew what was the norm.

The chrono will show you a number, it is what you do with it that counts, and this often leads to chronoitis. Barrels get burned out and constantly tested but not much gets achieved because the owner is never satisfied and destroys the barrel looking for the "Numeric" best and not looking at the actual results on paper. In many cases these tests are carried out well before the barrel is even shot in so the odd velocities may well be nothing to do with the load and all to do with minor copper build up.

My point? they can lead you down the garden path as well as being a help.