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What's it like to live in the Stone Age?

Having a chrono can help, but it is only part of the work up. I agree, knowing the velocity is good, but reloaders have to know what they are looking at, They have to be able to recognize problems with more than just velocity.

Mercifully, I do not. I have learned a lot over the years, but one is technology does not always make up for bad judgment.

If he sacrifices the correct color of chicken, yes.

But seriously, of course he can. He can schit in his own shoes if he wants to. Is it safe to load over-pressure? Likely. But the question becomes, "When does it become unsafe?" A few thousand PSI, say to 68K PSI MAP on a very consistent load velocity-wise, likely isn't going to be noticed, let alone likely unsafe.

Again, I have to look at all the companies who publish manuals. They have to assume that their readers will follow their instructions. It's never wise to ignore your manual unless you know what you are doing. Publishers cannot make that assumption, so not having a chrono won't put you in harm's way. Follow the manual's advice and everything will be fine.

I have not used my Chrony since I developed 400 grain Cape Buff loads for my Winchestrb1895 .405 WCF. There were good book loads to follow that included load and velocity, but not pressure. My Chrony and I matched them well , down to 1 foot second. This ammo was very carefully loaded with TAC and the results were gratifying. The final load matched the book exactly and the average shot to shot deviation was zero, so I stopped at 2076 fps for the .411 Woodleigh buff loads. FWIW, they were accurate and deadly in Africa.
I used my Pressure Test II to compare this ammo with factory Hornady 300 grain ammo and some of my other handloads. Pressures were safe, but still running above that stated in a couple of my load books. So, I switched to VV N133 which has a reputation for running 10,000 - 12,000 PSI lower than most popular powders and BINGO, same velocity 10,000 psi lass; actually dropped below 40,000 psi! Good for my Simson Suhl .405 DR also. Another Win Win deal!

So, it appears that my old Chony is still "good enough" for my needs for a few more years.

BTW, I hand loaded for my .308 at first until Hornady came out with Light Magnum ammo and I have used that ever since and it is accurate and my old M70 FWT loves it.

Steve,
I pointed out in a previous post that one must account for bbl length. Owning chronograph(s) for almost 40 years one of the first lessons I learned was about bbl length and velocity. Most manuals do list bbl length and some manual list the bbl manufacturer. Some manuals discuss their methods and equipment used.
I also learned that with various loads sometimes increases in powder when nearing max charge can result in little or no increase in velocity or vice versa. In my 243's I see a fair amount of change in velocity with seating depth of the bullet. That is also where a chrono comes in real handy. If I'm seeing max velocity with a load and want to seat the bullet closer to the lands, I take that into account and may decrease powder charge a couple tenths or so.

Back in the 90's some friends and I had virtually unlimited access to a Oehler M43 Ballistics Lab for a couple summers. We bought and glued a LOT of strain gauges on rifles. There was a steep learning curve with both the M43 and learning computers of the time, but one could see at times when pressure went up without much increase in velocity. Again, this always happened when we at, near, or over max listed powder charges. I've remembered that and have practiced my loading accordingly. When I stop seeing expected velocity increases when near max charge the odds are I'm at or over pressure. That is a rule of thumb but certainly has exceptions.

A chrono isn't a replacement for a pressure receiver and bbl, but it is a useful tool for a handloader.

Brad,
Thanks for the striking photo! Good Show!

I agree that the Chrony has its faults. I learned long ago that overcast days were my friend. But it really put an affordable chronograph in the hands of shooters back in the day, though most have upgraded to more reliable equipment. I used my Chrony for a physical science lab where the students fired a Styrofoam dart from a dart gun and measured velocity, then used the dart's mass and velocity to do KE and momentum calculations. Had to play with the lighting then too to make it work well.

I'm glad that you accept it's a tool. It will never replace common sense and knowledge. I will say this to you, and others in this thread. Some of you kept saying "I know...". This is not a swipe at you personally a/c, or anyone else who has responded. The manuals were not printed for you personally, but the general public. You might know what you are doing, but the companies don't know you. You shouldn't assume that others will take your advice and use it properly either.

When I was in the military, I worked for a man who used to smoke in the explosives storage area, That was where we kept propellants, and other explosive types. He broke the rules, and was caught twice, but always said, "I know the dangers and know what I am doing. I only smoke in empty bldgs." Until he caused a fire in the compound. Low explosive powder dust was on the floor when he put out his cigarette. Two lessons were learned. Housekeeping and stupidity.

This reloader can see both sides of this issue. Still, I fall on the side of spending the $90 to be sure.

I’m currently working with a long-throated 7x57 that’s been in the family for 4 generations. I carefully worked-up to the “family recipe” load, and found good accuracy with no outward pressure signs. While the rifle has many dozens of big game heads to its credit, the chronograph showed my 160 grain Partitions were being launched at a blistering 2,280 fps.

The “family recipe” was already over book max for the powder.

Nostalgia for the family history is wonderful, but I’m grateful I have a tool that can help me safely maximize the potential of this wonderful rifle.

FC


Edit to add: My experience with a Shooting Chrony was that, on those intermittent occasions when it did deign to display a reading, 'twas frequently erroneous. The device was perhaps better than imaginary toilet paper, but only slightly. I moved on to the PAL unit that's been strongly suggested in this thread, and have been very well pleased with it. The customer service folks there are excellent, too.

Steve,

Yes, common sense, knowledge and experience/info gained over the years make a chrono one of the most useful tools a handloader can own.

And we haven't even discussed cold weather testing...........

My use of a chronograph is twofold: 1) to catch any anomaly that might show up, 2) it's just kind of fun to have more data to mess with/records to keep.

All good points--especially about the Chrony putting an affordable chronograph in the hands of shooters.

My primary problem with them was in general they weren't very durable. As a result, you never knew when they might go slowly or quickly bat-schidt.

My may problem with them was in general they weren't very durable. As a result, you never knew when they might go slowly or quickly batp-schidt.

And that is why I started this thread looking for a place to get one repaired.

But this has been a very interesting conversation.

I thought I knew a lot about reading "pressure signs" until I actually began conducting pressure tests according the the SAAMI recommended procedures.

Having to learn the SAAMI procedures and conduct a fair bit of pressure tests made me go home and pull the bullets from my favorite 25/06 load.

I've blown up a bunch of guns. One was unintentional and resulted in significant injury (I was 16). I never want to experience another "pressure failure" unless it is at the end of a long string that is attached to the trigger.

My "Rule of string" for blowing up guns was to estimate how much I thought I needed and double it.

Velocity, in my opinion, is the best predictor of the safety of your loads. Measure it the way you feel is most appropriate for your situation.

Years ago I shot mine with a .375 Ruger.

Best thing i ever did.


Lefty

Curious stuff this. I purchased a Chrony about 22 years ago, and a friend did likewise about 10 years ago. The one I purchased is in other hands but they both continue to function properly. The one my friend has was set up behind a Pro Chrono a few weeks back and the spread between the numbers was low double digits. Something in the 20”s IIRC.

Luck is always a factor in life in human existence.

True, and I've always maintained it's better to be lucky than good.