Chronographs (high end) PVM-21, Oehler 35P

[Elwood]

I'm toying with the idea of buying another chronograph for load development and I want meaningful data every time, not just when the light is right, Cheap units are not an option! I have spent to many sessions being frustrated by no data or even worse incorrect data.

 

I already have a Magneto speed which is fantastic for the ease of use and correct data no matter what the light conditions are, but you can't use them (in my opinion) to actually do load development. For checking your loads I don't think there's anything better.

 

Does anyone have any experience of the PVM-08 ? This would appear to be the "best" unit,but I have several concerns.

 

Power supply?

Size of the sensor to shoot through.

The size of the unit for storing it when not in use.

 

http://www.kurzzeit.com/eng/bmc18.htm

 

I'm currently borrowing a Oehler 35P at the moment, which has a very good reputation and has been the benchmark for chronographs for years. It's reasonably straight forward in setting up and in using the unit, no thrills, no spills, does what it says it will do.

 

Or there's this one, which Christian highlighted in another thread.

http://www.mylabradar.com/

 

It isn't effected by light and you don't have to shoot through it and it also looks like it is very easy to set up, all plus points for me, but of course it hasn't been tested by the public yet. It would appear that it is not for sale outside of the US, but I can't see that being a problem. I would certainly like to see how it performs being used alongside the Oehler.

[terryh]

Ian,

 

I have a 35P ( but it is dead, again) which was 'the' chrono and still gives good results. I now use the magnetospeed which is so simple to use that it is doubtful I'd go back to shoot through designs.

 

Mr C has a PVM and as far as I've heard it's good but fragile and a bit temperamental.

 

Before dismissing the Magneto speed in favour of say the 35p I would have a look at the clock speed of each? The 35P's getting on a bit, if it is actually measuring to a larger slice of time perhaps the consistency of it readings is down to the fact it cannot see anything finer? It does give you two readings though, but if you are wanting to be that precise or confident run two Magnetospeeds

 

Just thinking out loud.

 

T

[gbal]

HI Ian,

Could you elaborate on you comment that the magneto is great for checking load (velocity) ,but can't be used for load development?

I've never owned a chrono,but thinking I need my own now-magneto seemed pretty good all round,and more convenient in use than screens-the few comparative tests seem to suggest it works pretty well too.

Gbal

[Ronin]

Ive used Garys PVM - it was great until it fell over in a gust of wind.

 

 

I also have a 35p - which appears to have a fault - it no longer reads, though powers up as normal, no idea what wrong (i'll send it back to Oehler for a service) - I've had it for over ten years and its never failed until recently.

 

I have a Magnetospeed V2, I disagree re load development, though I know where you coming from re barrel harmonics, simply get a load without it then check the velocities ,,,,,,thats how I do it with a barrel thats susceptible to the extra weight of they "magneto" attached.

 

 

The radar devices,,,,great if they work in civilian application and are reliable.

 

 

Not sure what is "best" as everyone has a different idea of what they need.

 

 

I want something thats accurate, unaffected by weather and easy to set up with good back up after service.

 

The Magnetospeed ticks all those boxes for me

[jcampbellsmith]

....I have a Magnetospeed V2, I disagree re load development, though I know where you coming from re barrel harmonics, simply get a load without it then check the velocities ,,,,,,thats how I do it with a barrel thats susceptible to the extra weight of they "magneto" attached.

..

 

Not sure what is "best" as everyone has a different idea of what they need.

 

I want something thats accurate, unaffected by weather and easy to set up with good back up after service.

 

The Magnetospeed ticks all those boxes for me

+1 on the above. My third chrono purchase last year was a Magnetospeed.

 

https://dl.dropboxusercontent.com/u/12296998/Magnetospeed/GAT%20Rifles%20260%20Rem%20%2B%20MagnetoSpeed.jpg

 

The first two didn't cut the mustard and went back.

 

Regards JCS

[Elwood]

Don't get me wrong, I love the Magneto speed and it's a keeper that's for sure, but it's just that you can't develope a load with it attached, as it acts as a tuner, I have plenty of data on paper to back this up.

Andy, I use the Magneto speed just as you do, I find a load that works and then check it with the Magneto to see what the velocity is and how high the extreme spreads and standard deviation are.

 

Take for instance a few days ago I wanted to see what difference different makes of primers made to a load that looked promising. I wanted to find out if the groups tightened or opened and what the velocity difference was between each make of primer. You can't get that information using a Magneto, or at least I can't as it I'm convinced it changes the barrel harmonics and if the Magneto moves on the barrel which they do it can and will the alter group size.

I ran that test through the borrowed Oehler 35p but unfortunately got wrong data which was down to operator error! I just think that if I'm shooting at a target and doing load development then I may as well get all the data I can while doing it.

[terryh]

Ian,

 

Gary and I talked about a discreet mount for the magnetospeed that went on the front of your front rest and held the magnetospeed where it needed to be, carbon fibre tube comes to mind, but nothing done in paper to look at realities of design.

 

T

[Elwood]

Ian,

 

Gary and I talked about a discreet mount for the magnetospeed that went on the front of your front rest and held the magnetospeed where it needed to be, carbon fibre tube comes to mind, but nothing done in paper to look at realities of design.

 

T

 

Neat, get on with it

[Elwood]

I'm seeing Gary this weekend so I will get his thoughts on the PVM-08.

[Ronin]

It would be my ideal to have the following

 

Ground mounted (not on tripod) screen (be that radar, sensor, or magnet) at or near the muzzle and another at the target, which had large enough screen or sensory area to allow testing out to 500 or further.

 

This would allow you to have a true reflection on bullet BC….

[taylor]

I have load developed tons of barrels mine and customers with the magneto speed then take it of and it still shoots lights out I don't know how yours in not working -

Yes impact will change but loads still shoot same groups

I think it's the best crono for the money out their

You don't need anything better

[Gary C]

Hi Ian/All

 

I do have a PVM 21, (in fact I have killed 3 of them) it was this frustration which got me involved with the Magnetospeed!

It does work IF your shot placement is good, however as I experienced last week if your a little left or right you get weird results, you may be asking why I was using it, and the reason was I was testing a tuner and did not want anything to muddy the water with harmonics, this is actually quite interesting as I gave up with the PVM as it was giving me readings 40 fps slower than my mag speed and the Es and Sd were vastly different, (verified with another unit a friend was using on this rifle shot thru the PVM.)..... So I attached the V2 to the barrel with the tuner and my best setting with the tuner was still the same as it was without the Magnetospeed. Grouping consistently in the 1's.

Not a very scientific experiment I know but it shows there was no harmonic effect to my barrel.

I met with the Magnetospeed guys at shot this year and we did discuss harmonics, they did explain that on a reasonably decent profile barrel there will be no harmonic effect, the POA change is due to the gases and blast exiting the muzzle with the bullet and gases

passing over the bayo.

The major problem with all tripod mount Chrono's is you have to sett them up and shoot thru them often with very frustrating results, as Andy said, my PVM blew over in a Raton twister...it smashed the sky screen which is now sporting duck tape and super glue (they really should make this stronger as at some stage it will get some abuse)

you can load develop with the mag speed mounted, all I do is get the load I am happy with then repeat it with the bayo removed, it does work for me even with a tuner.

This is not a sales pitch, just an account of some thing that I think will put your mind at rest .

Let's have a chat next week.

 

Cheers

Gary

[nowler]

hey g

 

grouping consistently in the .1's ?

 

you want to give up the f-class nonsense and go shoot benchrest, you'll clean up :-)

 

d

[Gary C]

Ahh Mr Newlands!

One day

No bullshit, with the correct tuner setting my .300 wsm produced 4 groups (3 shot) ranging 0.16 down to 0.11.

Hope your well

 

G

[nowler]

hey g

 

i'm ok thanks. i see you've gone down the large .30 as well? do you think the ballistics are better than 7mm and worth getting beat up every shot with? i think the kick is gonna become a problem with them. even if you think it's fine, your brain is not gonna like it and it will affect you....

 

i hope it works out however. i was playing with tuners before i sacked in competition in 2007. i think the jury is out on them but you seem to be having success. you might want to consider reverse taper barrels....

 

happy shooting

 

d

[aam]

This might be what you're looking for. I myself do not have this product. I think some of you would have already seen this though.

 

http://www.steinertsensingsystems.com/product/superchrono-standard/