Chronograph DO i NEED ONE

Trapper

Well-Known Member
I have loaded some . .243 loads
Powder VARGET , CCI primers , FEDERAL CASES.243 ONCE USED .
START LOAD 3I.00 GR in .5 increments , Max load by book is 33.7 , Have STOPPED at 33.5
Chrono readings by the book I guess are accurate , or do I try my own readings , having no experience of using a chrono . I have a willing person who has one.
Thoughts on a postcard gents/ladies .
Curious Trapper.
 
i really dont see the need to chrono anything yeah its nice just to know how fast your round is going but do you really need to know how fast its going? all you need to know is bullet drop (trajectory) and what its grouping at a given distance( most are happy with a inch grouping at 100yrds also known as 1m.o.a) after that the speed is uneccsery save your money dont buy a crono and just remeber a deer will not out run or dodge even the slowest bullet
 
I must disagree to the utmost! Without a chronograph you are shooting blind.

A chronograph does more than tell you the speed of a particular round if you pay attention to the data. Dual readings can be used to accurately determine the REAL ballistic coeffecient of a given bullet at your local altitude, barometric pressure and temperature... not to mention SPEED. "BC" changes with velocity. (Only) With an accurate BC you can utilize all those fancy ballistic programs that litter the Net.

Additionally, it is a pretty good tool for determining "diminishing" returns. Or rather, what is happening when you push maximum loads. If you chronograph, you will see the velocities begin to level with each increase in powder. When that happens you know that you are pushing the limits of that powder with that bullet. There are many powders that will, at the upper end of a load, exponentially increase pressure without significant velocity increases... and that can happen with a charge that seems to have some room left in it.

I have been using chrongraphs since they required a small truck to haul to the range and read in nano-seconds to be converted later. I wouldn't be without one and in fact, often use three simultaneously.

In short, get one if it's within your means.~Muir
 
It would be better to use one. Every rifle is different and the way a bullet seals in a barrel will differ which is partially responsible for pressure.
I must confess not to have used one yet, although we have one lying around. At the moment I zero at 100 and then shoot at 300m and adjust my drop chart. Even if I have the actual speed value I'd still need to check drop at longer range, but would then adjust bc.

Trapper I presume you are running 100 grainers with Varget in the 243.
My guess would be Varget is good up to say 85 gr in 243, from there on the max charge drops dramatically. from 38gr to 33gr . Maybe a slower powder would suit better.

edi
 
I would agree that a chrono is a must when reloading ammo.

I tend to use mine once I am getting tight groups.

When developing a load, I usually find that even up to 1-1.5gn difference in powder can give very similar groupings. Thats when I use the chrono. While you may have (for example) loads of 32, 32.5 and 33gn all grouping at 1", putting them thru a chrono usually shows that one of the loads is far more consistent than the others.

I also use the chrono to determine whether one powder is more consistent than another. I have loads for my 22-250 with around 8 different powders and all shoot sub 1" at 100yds. The chrono shows that Vihtavuori is much the more consistent powder for my rifle. Without a chrono I would have never known this

russ
 
To Chrono or not to chrono.

Trapper.
As Steve Latham so correctly puts it "let there be light". If you colleague has a chrono nick it. It will open so many doors that reloading will become an obsession. For all of the reasons mentioned above it is worth using a chrono but the most interesting aspect is it will show just how good (or bad) you are at reloading. Now there's a thought. Being consistent in everything you do is the key to successful reloading. Remember to give it back once you have done with it.

With the current prices of powder almost requiring a mortgage to purchase a couple of kilos give Vectan 7000 a try with 100g bullets. Very consistent and quick. Vih N160 is also very good with 100g bullets and at the other end, superb results.

Spiker.
 
Managed to get my batch of .243 chronoed today just 5 rounds . They where 2632, 2636 2636 2634 and 2639 .
my .308 where 2896, 2890 and 2897 only 3 rounds tested . These might seem a little slow but at least they are consistant.
cheers Trapper
 
What seems slow to you?? I don't know the bullet weights but they seem peppy enough. One of my favorite deer rifles tosses a 218 grain 30 caliber at 2000 fps. Slow but deadly.~Muir
 
Trapper said:
Managed to get my batch of .243 chronoed today just 5 rounds . They where 2632, 2636 2636 2634 and 2639 .
my .308 where 2896, 2890 and 2897 only 3 rounds tested . These might seem a little slow but at least they are consistant.
cheers Trapper


See you didn't need a chono, to get consistant results!

All that using the chono has done is put doubts in your mind with the velocities you are getting.

What bullet wieghts were you using 100gr in the .243, and 150gr in the .308?
 
Re: To Chrono or not to chrono.

Spiker said:
Trapper.
With the current prices of powder almost requiring a mortgage to purchase a couple of kilos give Vectan 7000 a try with 100g bullets. Very consistent and quick. Vih N160 is also very good with 100g bullets and at the other end, superb results.

Spiker.

I will second Vectan with 100gn bullet in 243 win, in my old Tikka they grouped just over 1/2" and were averaging a tad under 3000fps from a 22” barrel.

Trapper if you want to try some Tu7000 I have some spare as the old 243 is gone and the new 243 magnum don’t like it.

Best rgds

Tahr
 
With some cartridges towards the bottom of the deer legal range such as the 243/6.5x55 they can fall below what is deer legal for use in the UK.

Data given in reloading manuals is usually for a 24” or in some cases a 26” barrel or more. If you are using a 22” to 19” stalking rifle you could be using an illegal load. :cry: I have seen 308 home loads just scrape in the legal min’. :eek:

Another reason to chron’y your loads. ;)

Personally I load for accuracy first then check the velocity, providing it is deer legal I will use it.

You need a Velocity of 2850fps with a 100gn bullet and you will be big deer legal in Scotland, plus be safely in for England.

For Scotland what ever bullet weight you are using it must be travelling at 2450fps min’.

Best rgds

Tahr
 
Gents thanks for for your comments
With Varget I have 33.70 as my max load I am on 32.50 and still under
legal fps !! I know this now!! 8 x 57 muzzle energy , no I don't know how to yet , but someone will help on that score , and put me right .I am new to reloading . I found that my test loads at 33.50 lost some accuracy still sub 1" at 100 on pipe range . But I want to remain legal on my loads !! without the chrono, I WOULDN'T HAVE KNOWN I WAS under the recommended 2850fps !. I shoot 100gr on .243 and 150 gr .308
Thar thank you for your kind offer , I will pm you .For anyone just starting reloading It's a learning curve don't be put off !!. hurdles are meant to be jumped !!!. expect to knock a few over!!. :)
Regards Trapper.
 
Trapper where did you chrono the loads?

and with what chrono?

and how far fom the muzzle?

If it ws at the N/C pipe range you may have false readings depnding on the chrono.
 
Stand Buck
I used a chrono used by the range owner , model unknown , its his kit . I will look into the make , We set up table and chronoed at approx 3 Mt's . in the open into a solid bank!.
Regards Trapper( RUSS THANKS FOR INFO)
 
Trapper,
the easiest way to find out if your loads are deer legal is to enter your results in one of the ballistic calculators available on the web, many will also give you a calculation for bullet drop and wind drift.
The other way is to calculate the muzzle energy yourself using the following formulae -

Velocity (f.p.s) x Velocity (f.p.s.) x Bullet weight (grains) = Ft/lb
(divide by) 450240
 
Trapper,

Having looked up powders, even using Hodgdon's own figures you would struggle to get 2850 with a 24" barrel.

What OAL did you have as this can make a big differance to both pressure and velocity.


I would look at a slower powder better suited to heaver bullets such as IMR or H4831, IMR7828, N160, N560 or Vectan Tu7000.

SB
 
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