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Chronograph shopping ... Advise?
kimberkid
Member Posts: 8,858 ✭✭✭
For years I've thought I'd get a chrony but to date I haven't ... I've been reloading for 20 or so years and I'm now getting into subsonic rounds for both handguns and carbines. I'm looking at some new powders that are cleaner burning for my plinkers & varmint guns so I'll be needing to build some new loads.
In the past I've just varied my powder charge until I've obtained a satisfactory group size at a given distance; typically 200 yards. As I'm getting older, the trips down range are taking more out of me (asthma/COPD). Of course I'm using graph paper and a spotting scope but nothing replaces the satisfaction of walking down range and touching the actual target, rolling back the frayed blown out edges of the impact and seeing that group with the naked eye!
I'm hoping that if I record the actual speeds I'm getting with current loads I can reduce some of the trial & error experimenting building accurate loads with new powders.
In the past I've just varied my powder charge until I've obtained a satisfactory group size at a given distance; typically 200 yards. As I'm getting older, the trips down range are taking more out of me (asthma/COPD). Of course I'm using graph paper and a spotting scope but nothing replaces the satisfaction of walking down range and touching the actual target, rolling back the frayed blown out edges of the impact and seeing that group with the naked eye!
I'm hoping that if I record the actual speeds I'm getting with current loads I can reduce some of the trial & error experimenting building accurate loads with new powders.
If you really desire something, you'll find a way ?
? otherwise, you'll find an excuse.
? otherwise, you'll find an excuse.
Comments
I just listen for the crack above sub-sonic in the rifles.
In 40 years of reloading I think I have chronograph maybe a dozen loads on other folks equipment.
(snip) I can say this: the chrono has nothing to do with accurate loads.
That's interesting ... I always thought the speed of the bullet had everything to do with bullet stabilization and how tight of a group you could get as a result of that. I hadn't thought of it but its not out of the realm of possibility that the performance or burn rate of the powder would also effect the stabilization and accuracy.
quote:Originally posted by charliemeyer007
I never cared how fast they were going. A nice tight group tell me all I need to know. Standard deviation, velocity spread etc must be OK if the group size is small.
I just listen for the crack above sub-sonic in the rifles.
In 40 years of reloading I think I have chronograph maybe a dozen loads on other folks equipment.
That sounds like a whole bunch of common sense ... and that's how I did things back when I started reloading ... pick a starting point and then adjust my load by a grain and try it ... if it wasn't good enough adjust my load up or down a grain and see where I was going. When I was happy, I'd stop and that would be my load.
The only thing I worry about with subsonic loads is having a charge too lite and getting a bullet stuck in the barrel ... I've had one friend and one acquaintance have that problem and both ruined a barrel that way.
? otherwise, you'll find an excuse.
As for seeing the groups on the target, I've been giving serious thought to one of those TV camera/screens where the camera is setup a few feet from the target and displays it on the screen at the firing point. Sure beats walking out to the 600 yard line to see where your bullets hit.
quote:Originally posted by MG1890
(snip) I can say this: the chrono has nothing to do with accurate loads.
That's interesting ... I always thought the speed of the bullet had everything to do with bullet stabilization and how tight of a group you could get as a result of that. I hadn't thought of it but its not out of the realm of possibility that the performance or burn rate of the powder would also effect the stabilization and accuracy.
quote:Originally posted by charliemeyer007
I never cared how fast they were going. A nice tight group tell me all I need to know. Standard deviation, velocity spread etc must be OK if the group size is small.
I just listen for the crack above sub-sonic in the rifles.
In 40 years of reloading I think I have chronograph maybe a dozen loads on other folks equipment.
That sounds like a whole bunch of common sense ... and that's how I did things back when I started reloading ... pick a starting point and then adjust my load by a grain and try it ... if it wasn't good enough adjust my load up or down a grain and see where I was going. When I was happy, I'd stop and that would be my load.
The only thing I worry about with subsonic loads is having a charge too lite and getting a bullet stuck in the barrel ... I've had one friend and one acquaintance have that problem and both ruined a barrel that way.
The chronograph doesn't help. It only records velocity data. If a box of bullets came with a tag showing exactly how fast to drive them to get bugholes, then the chrono would help.
Power factoring for USPSA, IPSC, or IDPA.
BPCR. The old guns have high trajectories and uniform velocity is necessary to minimize vertical spread on target. Fortunately black powder will give standard deviation and even extreme spread in the single digits.
Long Range. Even high velocity smokeless loads need consistency to control the vertical. Uniform velocity does not guarantee small groups but it is necessary although not sufficient at long ranges.
Oh, yeah; at present I am using the Competition Electronics Digital Pro with remote control. Catch it on sale and it is not a whale of a lot more expensive than the Chrony, but it is a more capable device.
If I were doing a lot of chronographing these days, I would be saving up for a Labradar.
If shooting a rifle or even a long barreled revolver on a busy range, the Magnetospeed that attaches to the gun barrel is very convenient.
I have the Master with remote read-out.
has a sweet spot when it comes to velocity I have tested thousands of rounds in 45acp ON ransom rest. Found out early did not make much difference what powder was used as long as you got the same velocity with powder X as the best Groups with powder Y each weight and design has a sweet spot
BTW
There are only two kinds of all-in-one (units that have the sky screens and electronics in one box)chronographs--ones that haven't been used and ones that haven't been shot YET. If you get one that uses wires for the sun shields, I suggest replacing the wires with bamboo skewers or chopsticks. Those will shatter if hit rather than rip out of the holder damaging the unit.
Like Ray, my Chrony has been in use since about '86.
I have the Master with remote read-out.
Ditto, It works well and is inexpensive too.
The chronograph and Sky screens were hit many times by bullet fragments and other good stuff that comes out of a barrel when you're up around 70kpsi.
The Chronograph went back to the mfr several times for repair.
I cut a piece if 1/4" Lexan to tape over the readout to protect the electronics. It Works.
I'd recommend a remote readout and one that gives averages, range and std deviation.
Also, the distance between sensors is critical and for that reason wouldn't buy a folding unit.
I do not use a chronograph during the reloading process for finding a accurate load. I let the gun tell me what it desires for accuracy then eventually use a chronograph to check the velocity. I prefer a very accurate bullet going on target instead of a barn burner HV bullet not being accurate. I've seen a chronograph indicate what should have been a very accurate load, with low deviation, consistent vel, etc, and not be accurate on paper and I've seen a chronograph indicate that the load should not be consistently accurate and the load be very accurate, therefore I never use a chronograph when accuracy hunting choosing powders, bullets, primers, etc. I let the gun tell me what it wants then maybe test later with a chronograph just to see the velocity of a accurate load.
I found out I had to take with a grain of salt and high top boots what some of the big boys were saying about using their chrono's to find a accurate load. (the big boy testers doing their write up's were MOST likely being sponsored by the maker of the chrono in use and they could keep it free of charge if they wrote a good line of BS[B)])[:)]
The chronograph gives me a general idea of bullet drop/velocity for long range shooting/target practice.
Essential piece of equipment for reloaders, regardless of the blockheads that just watch for flattened primers or pieces of their guns floating by when they shoot super-hot, unverified or borrowed reloads. There's a reason SAAMI sets standards for pressure; fewer KBs!
Don't say by comparing velocity to published data...
How does a chronograph tell you chamber pressure???
Don't say by comparing velocity to published data...
Do a bing/google search and read!!!(and take the info with a grain of salt)
The only use I had for the chrono was for creating long range drop charts. Here, knowing velocity is vital.
Below are a couple of reviews ...
http://www.longrangehunting.com/articles/labradar-review-1.php
http://www.longrangehunting.com/forums/f19/chronograph-performance-review-148450/
quote:Originally posted by MG1890
How does a chronograph tell you chamber pressure???
Don't say by comparing velocity to published data...
Do a bing/google search and read!!!(and take the info with a grain of salt)
DITTO!
If you reach a specified velocity, you're likely coming close to the pressure stated in the data. Physics says equal force for equal output. Do as you please but when I reach xxxx fps, I figure I'm where I need to be and stop right there. I'm getting old enough that I don't need to find out how fast I can make something go once it goes as fast as I'm comfortable with.
One trick I learned the hardway:
If (like with the ProChrono) your chronograph has metal sky screen supports you may want to find an alternative that won't transmit the impact of an errant shot down to the chrono proper. In my case hard wood dowels of like diameter to the original steel work perfectly.
Haven't clipped any of them yet, but I did hit one of the old steel rods and the results were catastrophic.
I've had a ProChrono from Competition Electronics for years and it has served me well, though I could live without one if I had to.
One trick I learned the hardway:
If (like with the ProChrono) your chronograph has metal sky screen supports you may want to find an alternative that won't transmit the impact of an errant shot down to the chrono proper. In my case hard wood dowels of like diameter to the original steel work perfectly.
Haven't clipped any of them yet, but I did hit one of the old steel rods and the results were catastrophic.
Wooden or plastic rods is a good idea for the Pro Chrono. I could not believe that a bullet hit one of my steel sky screen rods a left a hole about size of a 30 cal bullet imprinted into the rod about midways of the rod and never broke the rod or the chrono and I never did know when it because the unit was anchored to a stationery anchored stand and the chrono still worked. Bet that ricochet shot went wild.