Chronograph neccessary for load development?

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tomapleleafss

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Hey everyone, quick question. I am just starting to get into reloading. I want to start load development for my 6.5 CM then, for my 308. I have done a lot of reading and see that many reloaders will use a chronograph during testing. I have spent all my pennies (the kids could just go work in Ontario and make as much as me right away) and I need to save for a good set of optics. My question to you is how important is a chronograph? Can I get by without one for a while or should I move it more to the top of the priority list? Much appreciated as always.
 
You can develop loads without one. However, when I started using one for my loads it really opened my eyes. The chronograph showed me how inconsistent some of my velocities were....when I thought I was being meticulous in my load methods. If you are serious about developing handloads, you'd be well served to include a chronograph in your system. As you know, consistency is a key to accurate shots :).
 
You don't NEED one, but it helps a lot. Even the cheap caldwell one help quite a lot. And not just to develop loads, it's usefull to chrono factory ammos too. To pre-calculate your drop at a distance, it's essential to know the initial velocity.

If you know someone else who also shoots, you can buy a chrono for 2 or 3 people. You don't use it everyday anyway. A cheap 150$ chrono split between 3 is less than a full of gas per person, and it'll be massively better than nothing at all.

I would say, however, that if you want to make loads with powder charges higher than the max published datas, it's essential. I wouldn't go past the max published datas without chronying the loads, even if there's no visible sign of overpressure.
 
Need, is such a strong word. :)

You don't 'need ' one. But if you actually want to know what your loads are doing by any data other than group size at one range, you may want one.
 
I agree with the post above...shooting a series of handloads of various charge weights and plotting the results on a chart provides some very useful information. You typically see a flat spot on the velocity vs. charge weight curve where the velocities don't vary much with small (0.1-0.2 or even more) variations in charge weight. This typically means that this range is more tolerant of small variations in charge weight. If you get groups with low vertical dispersion at this flat spot, you probably have found a robust load.

The savings in components during load development adds up - go for a higher-end chrono like a LabRadar if budget permits...it's a solid investment (and you can't but a round through a LabRadar as it lives on the line beside the rifle, not in front of it)...
 
The loading manual basically gives you a speed limit (speed = pressure) for each powder. As you load, you are looking for accuracy or consistency, but you should always be aware of where you are with pressure.

You can't easily measure pressure, but it is easy to measure speed.

You don't Need one, but you should Want one.
 
The info provided by a chronograph will save on ammo and reduce stress when shooting at longer distances and you are working on your dope tables. Ask me how I know......
 
You can develop loads without one and if you shoot at all distances to actually observe the POI rather than calculating the POI, you don't actually need to know the velocity to be able to hit what you shoot at. That being said, it's a nice to have. I have actually used the velocity reading to decide whether to continue to work up the load or not.
 
I'll put it like this: For the same amount of money, I'd rather have a Lee Press and a cheap chrono than an RCBS press and no chrono.
 
Alright then, sounds like I will be moving it up the list. I like the idea of trying to spilt the cost between a few guys. I'll ask around the see what I can come up with. Thanks.
 
If you do your load development at 200, better 300yds, the chrony only serves to ensure you are not exceeding expected velocity/pressure. Gives you a number to put into your ballistic program to get your drops close.

Until you can invest in a quality chrony, the data generated is not ideal and I would strongly suggest you rely on what the target at distance tells you vs a cheap chronie.

Many competition shooters going out to 1000yds have found tuning at distance is worlds better then wasting time and effort trying to generate fancy numbers on a screen.

And yes, chronie numbers even from a fancy chrony can be misleading wrt to what the bullet will actually do at LR.... only testing at the furthest distance you want to shoot at will.

Jerry
 
VinnyQC said:
You don't NEED one, but it helps a lot. Even the cheap caldwell one help quite a lot. And not just to develop loads, it's usefull to chrono factory ammos too. To pre-calculate your drop at a distance, it's essential to know the initial velocity.

If you know someone else who also shoots, you can buy a chrono for 2 or 3 people. You don't use it everyday anyway. A cheap 150$ chrono split between 3 is less than a full of gas per person, and it'll be massively better than nothing at all.

I would say, however, that if you want to make loads with powder charges higher than the max published datas, it's essential. I wouldn't go past the max published datas without chronying the loads, even if there's no visible sign of overpressure.
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Could you explain this to me please?
 
Andy said:
"Pressure Signs" are notoriously unreliable.

Muzzle Velocity = pressure as Ganderite stated.
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ahhh thank you. This answers a situation I am in now. Been reloading for a 270wsm using reloader 26. Worked up from 63.5 and loaded in approx.1/2 grain increments up to 69.3 grains. 69 listed as max by Aliant with a speed of 3210,/sec. I never had obvious signs of pressure anywhere so tried the 69.3. Best grouping by far but registered 3305/second.
 
I don't reload for long distance shooting, I reload for hunting, so I go for consistent grouping within 200yds to find the load that my rifle prefers to the bullet weight; then I stick to that load like an old dog and his one trick. lol

I rarely use my Chrony anymore while reloading - only when I try a new powder or am loading a new calibre and even then it is just for curiosity. Loading to the max has not yielded decent groupings on any of my rifles, so knowing the speed and worrying about over pressure is moot for me.
 
stubblejumper said:
You can develop loads without one and if you shoot at all distances to actually observe the POI rather than calculating the POI, you don't actually need to know the velocity to be able to hit what you shoot at. That being said, it's a nice to have. I have actually used the velocity reading to decide whether to continue to work up the load or not.
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stubblejumper is right but he should have went into more detail. IMHO the magnetospeed is far more practical and consistent than a chrony. Others may have another opinion.

Now, here is one way to get very close approximation of velocities if you can't afford one or are waiting for one. It works reasonably well but isn't as precise as a magnetospeed or chrony. Start with the suggested starting load. Say five cartridges. Shoot them at 100 yards. Use the same aiming point from a rest and don't try to make any adjustments. What you're looking to do is get a group on the target as a reference point

Next, load up five more cartridges with a stouter charge. If you're loading something like a 30-06 or 308Win I suggest 1 grain increments until you get close to maximum specs. I also suggest you load up all of these increments in one sitting so that you don't have to make a lot of trips over a long time to and from the range.

NEVER CHANGE YOUR AIMING POINT. WHY???? Because then you lose your reference point. With each increase, measure how high the impact is from your original group. This measurement will give you an approximate velocity. HOW??? Some manuals have reference tables, such as Hornady, which will tell you how high your trajectory is as different ranges with varying velocities. This reference will give you a pretty good idea of how fast your bullet is traveling.

It's simple but it works well enough for most uses and gives you a reasonable idea of pressure. The best early indication of high pressure I know of is sticky bolt lift after a cartridge is fired. When this happens, STOP. DON'T use any more cartridges with that load. DON'T use any with hotter charges either. Likely you won't have a KABOOM but you are approaching the limits of your brass at the very least. Go back and try the load just before the bolt lift was sticky.

Now, check which load gave you the tightest group and sight in for it. You may want to tweak it a bit by seating the bullet at different depths, which is often more important than reducing or increasing a powder charge. Chasing flyers is often fixed by changing to a hotter primer etc. When you change any component, you must start all over again. That includes different manufacturers of brass or different lots of brass and even powder/primers/bullets.
 
jerrya said:
ahhh thank you. This answers a situation I am in now. Been reloading for a 270wsm using reloader 26. Worked up from 63.5 and loaded in approx.1/2 grain increments up to 69.3 grains. 69 listed as max by Aliant with a speed of 3210,/sec. I never had obvious signs of pressure anywhere so tried the 69.3. Best grouping by far but registered 3305/second.
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Then you probably have pressure over the max listed in your reference. You're in overpressure territory without any sign of it. Your rifle won't explode or anything, but your brass might not live very long. Your whole rifle might not last as long as it would otherwise.

My point is exactly the opposite. My reference says max load is 33grn of powder and that will yield 1400fps. I have absolutely no reason to doubt my manual. At 33 grn I have 1250fps (let's suppose, for this exercise, that my chrony is 100% perfectly reliable). Same barrel length. So my velocity is lower and my barrel is the same length (it's actually the same gun as the one used by the reference), it means I'm probably under their listed pressure. Unless I have other signs of overpressure (I don't), it means I can increase the powder charge over maximum limit of my reference without much concern. The fact that I don't have the same velocity as my book doesn't mean the book is bad or my chrony is bad, it means something else is different (probably my powder is less powerful than the lot used by the author of the book, or we're using different primers).

Without a chony, I wouldn't even know that I can increase the powder charge past the maximum listed in my reference manual. I would not risk it. So I would stop there, and shoot underpowered loads.
 
VinnyQC said:
Then you probably have pressure over the max listed in your reference. You're in overpressure territory without any sign of it. Your rifle won't explode or anything, but your brass might not live very long. Your whole rifle might not last as long as it would otherwise.

My point is exactly the opposite. My reference says max load is 33grn of powder and that will yield 1400fps. I have absolutely no reason to doubt my manual. At 33 grn I have 1250fps (let's suppose, for this exercise, that my chrony is 100% perfectly reliable). Same barrel length. So my velocity is lower and my barrel is the same length (it's actually the same gun as the one used by the reference), it means I'm probably under their listed pressure. Unless I have other signs of overpressure (I don't), it means I can increase the powder charge over maximum limit of my reference without much concern. The fact that I don't have the same velocity as my book doesn't mean the book is bad or my chrony is bad, it means something else is different (probably my powder is less powerful than the lot used by the author of the book, or we're using different primers).

Without a chony, I wouldn't even know that I can increase the powder charge past the maximum listed in my reference manual. I would not risk it. So I would stop there, and shoot underpowered loads.
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You don't know that those loads are underpowered but it's a commendable rule of thumb. Many rifles will reach maximum pressure very quickly for a number of reasons such as oversize chambers, fast twist rates and rough bores. By rough it can be anything from corrosive pitting to riffling chatter. It can also be from tight bores and several other issues which can show up even with starting loads. I've had this happen. It happened with a lovely little Mannlicher 6.5x54 custom rifle. It didn't matter which factory loads I used, the bolt lift was always sticky. It wasn't until I used handloads with 130 grain bullets. The bore was extremely smooth and measured out at .262in. The combination was enough to raise pressures well above those specified and when they were checked over a chrony the velocities were well within the range they should have been with 160 grn bullets.
 
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I think they are needed. However, i got a load done (100 yard testing only) without one till yesterday. I have managed a 4 shot .358" CTC group. Took two fouling shots before hand on a clean barrel. I used my chrony ( finally ) for the first 3 shots, ( so velocity from two foul shots and one from my group, not ideal I know) and got an ES of 17. Velocity was as follows, 1st 2706, 2nd 2691, and 3rd 2689. I have lots to do yet with this load but it turned out very well so far. Point is I never used it to work up a load, ( weather and I forgot my adapter once ) but checked the numbers afterwards. It can work ok.
 
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