Buy a chrony!

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prosper

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I just went to the range today with my brand new chrony. Every reloader NEEDS one of these. I found wide variations in speed between my rifle and the load manuals. Both my hornet and 22-250 were almost 200fps above published specs for the specified powder charge. :D

SKS milsurp ammo is right on the line at 2400fps
22 rimfire stinger & remington yellow jackets were as advertised, as were hornady 17HMR cartridges.

Most disappointingly, my .204 was 300 fps slower than the load manuals indicated I should be at that charge :(

Anyway, it's very eye-opening. If you don't have one, get one.
 
I have a PACT Professional = $350 delivered after the exchange and duties.

Shooting Chrony is good for most people.

You have, in addition to the above - CED, Oehler, Competition Electronics.

There may be others too.

RePete.
 
I'm back into shooting the last 5 years or so. Used to shoot a lot when I was in my teens and 20's. Used to read everything I could get my hands on back then, Gun Digests, magazines.
Back in the 70's, even the magazines and writers had to go to a lab to use a chrony - they were thousands of dollars and had wire screens etc.
When I found out that chronys were around $100, it's almost the first thing I bought, even before I started reloading.
 
RePete said:
Shooting Chrony is good for most people.

RePete.
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Another plus for Shooting Chrony http://www.shootingchrony.com/ is that they are made in Canada (Mississauga Ont.) So "if" you shoot a hole thru it repair/replacement is less hassle. Then when your buddy shoots two holes in it repair/replacement is still less hassle.
Beleive me... I know:D
 
Great eye opener, and good way to make sure your loads are not over pressure. Have a Beta master, would like a Oheiler Ballistic laboratory, but would also like to own an aircraft carrier......some day
 
I got a Shooting Chrony for Christmas and haven't had a chance to use it yet.
So other than knowing the exact velocity of handloads and their consistancy I would appreciate some information on how I can use this information, eg. does the "sweet spot" for different loads occur at the same velocity?
 
So other than knowing the exact velocity of handloads and their consistancy I would appreciate some information on how I can use this information, eg. does the "sweet spot" for different loads occur at the same velocity?
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Velocity = Pressure. If your chrony is showing more speed for a given load than what the books say, you need to stop early for your particular rifle. Mind you some rifles will handle more pressure than others, but that's another story....

"Sweet spots" will occur at different velocitys for different bullet/load/rifle combinations. But, you will now be able to record at which velocity the sweet spot occurs and be able to reproduce it in the future. ;)

I just started reloading about a yr ago. I didn't have anyone to show me anything so I'm self taught 100%. My biggest safety net in this little venture is my chrony. I cheap little Ohler F1 for like a hundred bucks. :)
 
I have the F1 from shootingchrony, it works great for my needs. I use it when I am working up loads to judge pressure. If I am at or near the velocity listed i a manual I stop. Sometiems that is slightly over the powder charge listed and just under.
 
I reloaded for 15 years before I bought a chrony, what a mistake. The quality and performance of my reloads have now been maximized with the additional information that I now have available to me. Wish I had done it sooner.
 
They are great,not just as a pressure gauge,but for load developmeent with different combinations.In my 338.06,with N-550 and 225 Hornadys,there no data.I after recording the velocities,I got the velocity increase/weight and extreme spread.

Even those who shot factory,need to put one over. One of my buddies has a 30-06 carbine 760, his velocities were the same as the published 308 balistics.This is handy,now he can use 308 drops.
 
Velocity = Pressure. If your chrony is showing more speed for a given load than what the books say, you need to stop early for your particular rifle
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While more pressure generally means more velocity,this is not always the case.Two rifles with equal length barrels may produce the same velocity,but that does not necessarily mean that they are producing the same pressure.Every barrel is slightly different as far as dimensions and bore finish,so some will produce more velocity than others while producing the same pressure.
Then you have to take into account that there are great variations in velocity from manual to manual,even using identical components and equal length barrels.Five different manuals can use the same barrel length and the exact same components,yet the velocities mighty vary over a range of up to 200fps.Yet all claim to be loading to the same standard pressure for the given cartridge.So why the difference?Because the people producing each manual used a different barrel to develop loads in,they end up with different results.
So it is not as simple as picking a load and increasing the powder charge until the velocity equals that in one of the manuals,and then assuming that you have the maximum safe load for your rifle.If you pick the manual with the highest velocity,your load may not be safe in your rifle.If you pick the manual with the lowest velocity,the load will likely be safe,but not likely be the maximum load.
Temperature is also a factor.A load developed at 10 degress C might produce excessive pressure at 30 degrees C.A load developed at 30 degrees C will be safe at 10 degrees C,but will likely produce noticeably less velocity at the cooler temperature.
To sum it up,the chronograph is a great tool to have but it only measures velocity,and can't be used to accurately determine pressure.
 
Definately get a Shooting Chrony that has the remote readout display. They're made in Missisauga Ontario Canada. If you shoot the ears off (which I did) you can get it replaced very easily. Also another advantage of the remote readout is if you shoot your chrony (which I did-kind of) it's easier to replace the sensors than the digital readout display. And ditto to what stubblejumper said. You can't rely on a chronograph for pressures. It is meant to read the speed of your loads. Good luck!
 
I would qualify the "using a chrony as a presure guage"
-Use standard barrels,Remington,Winchester,etc and NO foreign barrels,you just don't know!!
-Use suitably slow powders.like 4350 with 180gr in 30-06
-No copper clad (Swifts)or solid bullets(Barnes),simply too high a friction bullet for pressure equals velocity equation to work.
-25f/s per inch difference than the specs barrel.
-Do check data,Hodgdons 338.06 data is for AI version,I caught that looking at the drawing.
 
Use standard barrels,Remington,Winchester,etc and NO foreign barrels,you just don't know!!
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Reguardless of manufacture,barrels,chambers and throats do vary a great deal.I have chronographed the same load in three different remington 700bdl ss detachable mag rifles on the same trip to the range and the velocity varied by approximately 100fps.These were three supposedly identical rifles bought at the same time by three of my hunting partners.All components were identical and from the same lot#.

I personally have owned three 7mmstws and still own two.All three barrels were cut with the same reamer and all are 26" long.All three barrels are premium barrels made by well known barrel makers.Using identical components the three rifles produce velocities varying by 120fps before any pressure signs are evident.This is proof enough for me that some barrel will simply produce more velocity with a given pressure.
 
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"This is proof enough for me that some barrel will simply produce more velocity with a given pressure." Stan Watson,a balististician, did a bunch of work with Oheler 43?,the one with strain gage. He came to believe that there no such thing as fast barrels ,only slow.more pressure,less velocity

That very interesting the effect of barrel friction on an overbore cartridge.Those are hard numbers,that's just bullet bearing surface friction.My hunch from reloading the 264WM is that as your bore/case capacity lessens,so would the barrel friction effect.BTW I have seen over 10% velocity loss from a bad barrel.more pressure,less velocity

Still,as John Barness has said,the chrony is the best pressure indicator the average handloader has.
 
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Some of the advantages

of using a Chronograph in load development is you can see what your loads can and will do when changing powder lots. If you have a load that shoots with a certain lot of powder it may aid you when changing lots of powder to achieve the same velocity thus possibly keeping your gun in tune. Just because a given lot gives X fps does not mean that the next lot will give the same. We still must watch for the other signs as well, those being actual signs of pressure. A good example of this is from a US based BR shooter who uses Kreiger barrles and Bart's 68gr Ultra's in his 6PPC. He says that with his barrel/reamer/bullet combination as long as he keeps the velocity at around 3450 fps he is very close to his tune and may just have to tweak it ever so slightly. I feel that the chronograph aids in this when changing barrels or powder lots.

The advantages for the long range shooter are that of finding the best load that will keep the SD and ES down thus tighter groups at longer yardages.


JMO
 
Stan Watson,a balististician, did a bunch of work with Oheler 43?,the one with strain gage. He came to believe that there no such thing as fast barrels ,only slow.more pressure,less velocity
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It really doesn't matter whether you refer to them as normal barrels and slow barrels, or normal barrels and fast barrels,or fast barrels and slow barrels.The point is that he is agreeing that some barrels do produce more velocity than others ,while developing equal pressure.If that was not the case,all of the loading manuals would have the same maximum velocity for their maximum load with a given bullet,brass,powder and primer combination.Anyone that owns several loading manuals is well aware of the differences in velocity between the varying loading manuals.

As for Barnsness,he is entitled to his opinion just like everyone else.Just remember that he is a writer,not a ballistician, so his opinion has no more credibility than any other experienced reloader.

Just one more thing to ponder.If the chronograph really was a reliable way to estimate pressure,why would oheler,probablly the most respected name in chronographs, even bother to manufacture their m 43 pressure measuring equipment?
 
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