Tell me about Chronographs [Archive] - Glock Talk

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coachg
05-20-2010, 11:07
I'm at the stage in reloading where I'm really happy with my ability to make ammo for several different calibers efficiently and safely. I'm able to shoot alot more for the same amount of money which is great.

It sounds like in order to take it to the next level you should have a chronograph. It may not be necessary, but it seems like if you want to enjoy the reloading process even more this is a good next step.

Can you tell me what the benefits of using a chrono are? Do you look to get your loads as consistent as possible? Is that what brings about better accuracy? I'd really like to learn more about it and figured there are plenty of you guys out there who can give me some good advice.

I'd also be interested in which brands you recommend. I'd be using it at a public range so I think one with a remote would be highly recommended.

Thanks,

CG

XDRoX
05-20-2010, 11:20
Since my name will probably get brought up somewhere in this thread (just a matter of time before Jack sees it), I might as well just go ahead and post the picture.
http://members.cox.net/chrismosteller/chrony.jpg
My new chrono has the screens separate from the unit. Ingenious design IMO:supergrin:

GioaJack
05-20-2010, 11:51
Since my name will probably get brought up somewhere in this thread (just a matter of time before Jack sees it), I might as well just go ahead and post the picture.
http://members.cox.net/chrismosteller/chrony.jpg
My new chrono has the screens separate from the unit. Ingenious design IMO:supergrin:


Owning up and admitting to a mistake has become a rarity nowadays and sets a more important example to your students than you might realize. Good for you... it's a more important aspect of being a man than knowing how to shoot.

The downside is that you've taken the fun out of ridiculing you... never fear, you'll screw up again and we'll leap upon the opportunity. :supergrin:

Coachg:

Having a chronograph is not a necessity in loading but it is, without question, a helpful tool. It partly depends on your shooting goals and needs.

I went well over 45 years without owning one, my needs never dictated it. I loaded and shot to increase my skill and muscle memory, velocity of my loads was not a major concern since I was required to carry issued ammunition in the uniform gun and approved factory ammunition in everything else. This is not to say that I never used a chronograph but there were always friends and fellow shooters who had them.

Be it due to boredom, new toy syndrome or lack of fiscal restraint I recently purchased a CED M2. The price is reasonable at $199 and change and seems to do much more than I require.

Being one that has trouble hitting the ground with a bowling ball I am appreciative of the fact that the electronics and display panel are connected to the screens by 20 foot cords and can be placed next to you on your shooting stand or on the ground. This does not guarantee that it's out of my line of fire since the safest thing to be is what I'm actually shooting at but it does decrease the odds of being hit.

If your knowledge of computers extends past knowing how to turn on the power switch the software that comes with it may be of interest. Apparently it allows you to design very detailed spreadsheets incorporating Hi-Lo velocities, SD, Power factor, etc., etc., etc. I find a legal pad and pencil to be much less complicated but I also find sliced bread to be a bit intimidating.

There are chronographs of better quality and I imagine lesser quality out there and I would suspect that your choice would partly be determined by budget.

If you take XDRox with you to test one out... let him sit in the car. :whistling:


Jack

HAMMERHEAD
05-20-2010, 12:36
I've been using a friend's Chrony on and off for the past year. Once I started using it, I hate to be without it. Most loads are close to what they should be from the books, but sometimes the Chrony can be a real eye opener.
I feel a lot more confident getting near max velocities with 9mm and .38 Super when using the Chrony.
With revolver cartridges where I usually load down, the Chrony lets me know that I need to speed things up to manly levels.

fredj338
05-20-2010, 12:44
I have been reloading w/ a chronograph since they were made w/ paper screens! Yes I can reload w/o one, but they are helpful & can help keep you out of trouble whne working w/ unknown component combinations. All things being equal, pressure = vel. So if you change seating depth, you can see vel increase, that is also pressure increasing. Same for swapping primers or bullet types. It's almost invaluable when working w/ calibers where no printed data is to ba had (wildcat or obsulete carts).
Buy quality (read, NOT a CHRONY) IMO. All chronographs do the same thing but not are all the same. The biggest diff is in the sky screen quality. Chrony has some of the worst. The CED is at the top, the Oehler is THE BEST of the hobby chronographs, because of their superior screens.

coachg
05-20-2010, 13:40
Fred and Jack, I think i like the design of the CED M2 for the same reasons Jack described. Looks like you can buy a replacement sensor fairly inexpensively if you do what XD did. :supergrin:

Regarding its use for pressure, I want to make sure I understand. If you have published data for a particular powder and bullet weight you want to be careful not to exceed the max velocity regardless of whether your powder charge is over the limit or not. This would tell you if something else was off like the seating depth, primer, etc. Is that correct?

As you work up loads, do you see changes in SD as you increase or decrease the charge and then settle at a point where you get the lowest SD? Is that generally the point of greatest accuracy?

It sounds like it would be fun to use, I'm just trying to understand how it can help my shooting and ammo accuracy.

GioaJack
05-20-2010, 14:12
coachg:

Think of published data as a 'report' of what occurred under a given set of circumstances... those which you may, or may not be able to replicate. They are a guide, a map if you will that directs you to a neighborhood but not a specific house.

Different companies use different equipment and conditions when they determine pressures, velocities, etc. Some use pressure barrels of a certain barrel length while others use actual firearms of a specific make and model. There are other factors involved that a loader would probably have no knowledge of such as temperature, humidity, elevation and I suspect a myriad of other variables. These would account for minor variations but have an effect none the less.

As you may already have noticed, three resources may publish different data for seemingly the exact same load... not at all uncommon. You may also have noticed that the data will be relatively close to each other. (I guess we can't discount the lawyer factor when trying to interpret published data.)

The use of a chronograph will serve several purposes. If you are not versed in reading physical pressure signs, or have a situation where none are apparent the chronograph will alert you when a velocity exceeds expectations based on published data. Heed it as a warning, determine the problem and rectify it. Obviously a situation such as this falls into the realm of safety and if it happens only one the chrono already paid for itself.

The 'fun factor' of a chrono is in developing the most accurate and efficient loads possible. New loaders quickly learn that velocity does not always equal accuracy and conversely low charges of certain powders result in poor accuracy because of unacceptable SD.

The use and understanding of a chronograph can greatly enhance the understanding of ballistics, why and how your loads do what they do, which in turn makes you a better and more rounded loader.

Remember one thing however, a chronograph is not something you have to drag out with you to every range session. There's a lot to be said for spending a few hours shooting the X out of bullseye targets, hearing steel clang or stuffing your pockets full of folding green from side bets with the pilgrims.

Good luck, have fun and don't shoot anything you don't intend to.

Jack

coachg
05-20-2010, 14:41
Thanks Jack.

The safety factor makes perfect sense.

So is it the variations in velocity that will lead to poor accuracy? Is that what makes one powder/bullet combination more accurate than another? I never understood how one powder could be more accurate than another. I can understand how one gun or shooter can be, but the powder?

GioaJack
05-20-2010, 15:14
To take the easiest answer first... Think of powder as your golf swing. You're aiming to put a succession of golf balls inside a hula-hoop a hundred yards away with your 9 iron. Your first swing is perfect, the ball drops in the hoop. Your second swing is less powerful and the ball drops short, the third has too much force and sails over your target, the fourth is perfect, the fifth... well, you get the idea.

Repetition is the key to accuracy, be it a golf shot or a gunshot. Consistent hold, sight picture, bullet weight and velocity. Unlike a golf ball however, where dropping it within five yards of where you intended the benchmark of bullet accuracy is the ability to put shots into the same hole. These days accuracy is most often expressed in grouping at 7, 10 and 15 yards whereas not too many years ago the goal of developing a load was to put 5 shots into a 1 1/2 inch X ring at 25 yards standing on your hind legs with the strong hand. To accomplish this absolute repetition of every factor is imperative.

Another factor to consider is burn rate of each powder. (Burn rates are in almost every quality loading manual or can easily be looked up on the internet.) Basic, (very basic) rule of thumb is light bullet at mild to mid-range loads tend to work best with the faster powders, heavier bullets at higher velocities tend to work best with slower burning powders.

I am the first to admit that there are many, many folks on here who know a hell of a lot more about powders than I do... Fred being at the top of the list. I started loading when you really only had 3 powders on your bench for handgun calibers; Bullseye, Unique and 2400. For any short coming they may have had, (or still do), you simply learned how to overcome them by experimentation and thousands of hours of practice.

I'm sure there are some powder/bullet combination that produce such poor accuracy it would be difficult to hit the broad side of a barn if you were standing in it but for the most part I'd say that the majority of reasonable combinations produce better accuracy than most shooters are capable of holding.

Wait around for Fred or some of the other guys... they'll be able to explain it better.

Jack

coachg
05-20-2010, 15:21
Good explanation. I'm starting to get it.

robin303
05-20-2010, 19:06
I got my new chrono yesterday and spent the whole day at the range playing with it.
Started off shooting nothing but factory rounds of every brand I can buy around here in 9mm and 40 S&W then shot my reloads in all the grains of 9mm and 40 and with 5 differant powders. Sure did open another door in reloading for me anyway.
It is on sale and this is what I got and I did get the tripod from Best Buy for $34.00
http://www.midwayusa.com/viewproduct/?productnumber=852429

Gunnut 45/454
05-20-2010, 21:04
XDRoX
I made that mistake in my first chrony as well - with the same fate as yours but more dramatic- 454 Casull 300 gr cast load at 1600 fps! Needless to say it was a quick death but gross!:shocked: Like Jack, my new F1 has the seperate screen at the shooter station ! But I already have a gas check inbedded in my back sensor! Still fuctions perfectly though!:supergrin:

XDRoX
05-20-2010, 21:45
XDRoX
I made that mistake in my first chrony as well - with the same fate as yours but more dramatic- 454 Casull 300 gr cast load at 1600 fps! Needless to say it was a quick death but gross!:shocked: Like Jack, my new F1 has the seperate screen at the shooter station ! But I already have a gas check inbedded in my back sensor! Still fuctions perfectly though!:supergrin:

300gr 454:wow: That would have been quite a show:supergrin:

_The_Shadow
05-20-2010, 22:24
Chris, OUCH you Chrony's got a hole thru it!

I have an eight foot long saw horse that I mount my F1 master CHRONY on, the CHRONY sits below the 8' long 2x4 on the end of the horse as this provides some good protection for the instrument. Bullets slide along the top of the 2x4 so the CHRONY doesn't get hit. The long surface also provides a level surface in which to keep shots level over the screens. It has the 20" long cord with the display so it is right next to the shooting position. I also made a small momentary push switch on a 3.5mm jack to use to access the other data which is avalible by pushing the switch.

Also I use bambo skewers as the uprights, I haven't shoot any yet, but some day it may save the detector screen units from the shock, as the skewers will snap off if struck.( the metal rods if struck send enough energy to the detector screens to cause damage)

Happy shooting!

Gunnut 45/454
05-21-2010, 09:24
XDRoX
Yep and it was prefect dead center shot! It flew ten feet with tripod attached! Like I said ugly!:wow:

bulletguy
05-21-2010, 10:33
XDRoX
Yep and it was prefect dead center shot! It flew ten feet with tripod attached! Like I said ugly!:wow:

After my grandson "punched out" my first Chrony :faint: a few years back, I was able to find an F-1 Alpha with remote readout and control. Not wanting to take the same chance of him blowing out the new one, I decided to set up a paper target about a yard or two beyond the screens so the center of the bull is right where I want the bullet to pass through the screens. You simply aim for the target center and fire away and you are in no danger of hitting the Chrony. After doing this, we have never had a problem again. :cool:

fredj338
05-21-2010, 14:45
After my grandson "punched out" my first Chrony :faint: a few years back, I was able to find an F-1 Alpha with remote readout and control. Not wanting to take the same chance of him blowing out the new one, I decided to set up a paper target about a yard or two beyond the screens so the center of the bull is right where I want the bullet to pass through the screens. You simply aim for the target center and fire away and you are in no danger of hitting the Chrony. After doing this, we have never had a problem again. :cool:
I accuracy test while chronographing, rifle or pistol. I have yet to splat my screens. I never did like the idea of shooting at the chrono itself, seemed kinda self prophesizing doing some damage to it.
Yes, not needed, but to a serious handloader, pretty valuable tool.

njl
05-21-2010, 18:00
Since my name will probably get brought up somewhere in this thread (just a matter of time before Jack sees it), I might as well just go ahead and post the picture.
http://members.cox.net/chrismosteller/chrony.jpg
My new chrono has the screens separate from the unit. Ingenious design IMO:supergrin:

I think you're shooting a little too close to the sensors...and under them.

To the OP, IMO, if you're reloading, you need a chronograph. Otherwise, you have no idea what velocity you're getting, and all you have to go on is accuracy, reliable function, and any really obvious signs of overpressure. Your scale could be off. Your powder could be hotter than the manuals you have expect.