Chronograph for small caliber high speed bullets???

[Extreme Accuracy]

Is anyone out there having decent results with their chronograph on the small caliber high speed rounds?

I wasted a good portion of my range time today struggling to get readings. After spending all the time it takes to set it up with the infrared kit and muzzle blast baffles and then have it sit there with a blank screen drives me crazy.

As soon as I tried to run my 14 calibers over 4600 fps it would start missing shots. The highest I could even get was 4760 fps. Swapped start and stop gates, swapped the infrared panels, tried backlighting, top lighting, low passes over the sensors, high passes. The bullets are even coated which should in theory help.

As hard as it is for me to get range time in these days the last thing I want to do is waste it trying to get a chronograph to read shot strings.

Thanks for any recommendations you might have,

Carl C.

Extreme Accuracy

[georgerkahn]

Is anyone out there having decent results with their chronograph on the small caliber high speed rounds?

I wasted a good portion of my range time today struggling to get readings. After spending all the time it takes to set it up with the infrared kit and muzzle blast baffles and then have it sit there with a blank screen drives me crazy.

As soon as I tried to run my 14 calibers over 4600 fps it would start missing shots. The highest I could even get was 4760 fps. Swapped start and stop gates, swapped the infrared panels, tried backlighting, top lighting, low passes over the sensors, high passes. The bullets are even coated which should in theory help.

As hard as it is for me to get range time in these days the last thing I want to do is waste it trying to get a chronograph to read shot strings.

Thanks for any recommendations you might have,

Carl C.

Extreme Accuracy

Sorry to read of your frustration! I "started out" with an antique (new back then) Oehler with which one shot through two pieces of paper, then reading "Nixie Tubes" to determine velocities. My newest kid is a LabRador, but all I've clocked with it has been in the <2,000fps range. I do have an Oehler 35p, and it has yet to fail me, and it should be ok at your velocities.
You did NOT indicate the make, model of the chrony you are trying? I also have a PACT with an Infrared Kit -- so, this may be similar? (Just a pure guess!)
Regardless, for what it is worth, if you have separate start and end sensors, what would happen if you doubled the distance between them? I'd shoot, say, a string of shots with known (lower) velocities and record an average. Then, as stated, double the screen distance, recording the velocities you now get.
Then, try your hi-vel rounds -- if recorded, then simply do the math -- similar percentage reduction as low-vel rounds.
Oh -- again, as you did not mention brand and model of your chrony -- might the range you seek be out of it's spec limits? Another possibility .
Good luck!
geo

[elmacgyver0]

That seems awfully fast, but I am old school.
Just out of curiosity, what exactly are you shooting?

[Extreme Accuracy]

Geo, I don’t like to post the brand as the company did work with me years ago to try to get the chronograph to work with the small calibers. It is a CED millennium which even with the purchased extra IR kit and blast baffles just isn’t up to reading the small caliber high speed rounds. I believe their newer unit is supposed to be good up to 7000 fps from their advertisements but I’d really like to know what caliber bullets they are reading those velocities with.

I have spent time over the Oehler 35P chronographs way back in the day. They did do a great job of reading the 17 and 20 calibers we were shooting back then. We were normally running them in the 4000 fps range and the Oehler (with back lighting) did pick them up pretty consistently. I’m not sure if they can read up to or over 5000 fps range. I may need to call them now that they are producing the 35P’s again. I have not run any of my 14 caliber rifles over one to see if it reads the smaller bullets either.

I was hoping that there might be others on this site shooting the 14 calibers that might be having luck with their chronographs.

Spacing the sensors out helps if both sensors see the bullet but getting both to read the bullet is the heart of the problem.

Thanks for any help or information you can provide,

Carl C.

Extreme Accuracy

[Extreme Accuracy]

elmacgyver0, I shoot a lot of 14 caliber rifles. The upper end on the speed range are 14/221 Walkers and the 14 TCM Extreme.
Even the little 14 Hornet Extreme and 14 Bee will have troubles being read by the majority of chronographs I've tried.

The combination of small bullet size and the higher speeds makes it difficult to get readings. I shoot mainly coated bullets so darkening the bullets doesn't seem to help either.

Carl C.

Extreme Accuracy

[BLAHUT]

I use, MAGNETO SPEED barrel mounted with great results.

[Extreme Accuracy]

BLAHUT, will the MAGNETO SPEED read in the 5000 FPS range? Does it read the small calibers? (14 and 12 calibers?)
I was under the impression from previous searches of their product that they only went to the 4000 fps range. Do the newer units read higher then that? Can you let me know what the fastest speeds you've been able to pick up with yours is?

Thank you very much for any information you can share about it.

Carl C.

Extreme Accuracy

[georgerkahn]

Geo, I don’t like to post the brand as the company did work with me years ago to try to get the chronograph to work with the small calibers. It is a CED millennium which even with the purchased extra IR kit and blast baffles just isn’t up to reading the small caliber high speed rounds. I believe their newer unit is supposed to be good up to 7000 fps from their advertisements but I’d really like to know what caliber bullets they are reading those velocities with.

I have spent time over the Oehler 35P chronographs way back in the day. They did do a great job of reading the 17 and 20 calibers we were shooting back then. We were normally running them in the 4000 fps range and the Oehler (with back lighting) did pick them up pretty consistently. I’m not sure if they can read up to or over 5000 fps range. I may need to call them now that they are producing the 35P’s again. I have not run any of my 14 caliber rifles over one to see if it reads the smaller bullets either.

I was hoping that there might be others on this site shooting the 14 calibers that might be having luck with their chronographs.

Spacing the sensors out helps if both sensors see the bullet but getting both to read the bullet is the heart of the problem.

Thanks for any help or information you can provide,

Carl C.

Extreme Accuracy

"My" small calibre guru was a fellow named Todd Kindler of the Woodchuck’s Den, a firm which specialized primarily in the 17s and the 20s. I believe Mr. Kindler retired, but if you Google (last I heard he still does consulting) him -- he, if anyone, may be able to provide chrony info vis your 14s. From my teeny-teeny experience with small calibre chronying, a major challenge I had was the lighting. I tried, with mixed results, using colour filters (borrowed from a Drama department's "junk" box) over lights which helped. But, this was pre-Bluetti/Jackery/etc. days and the challenge was getting a.c. to range to power the lights... For me, blue was the colour of choice.
BEST wishes!
geo

[577450]

Out of curiosity, what do your targets look like at that velocity?
Are they stable enough to make it all the way?

[Extreme Accuracy]

"My" small calibre guru was a fellow named Todd Kindler of the Woodchuck’s Den, a firm which specialized primarily in the 17s and the 20s. I believe Mr. Kindler retired, but if you Google (last I heard he still does consulting) him -- he, if anyone, may be able to provide chrony info vis your 14s. From my teeny-teeny experience with small calibre chronying, a major challenge I had was the lighting. I tried, with mixed results, using colour filters (borrowed from a Drama department's "junk" box) over lights which helped. But, this was pre-Bluetti/Jackery/etc. days and the challenge was getting a.c. to range to power the lights... For me, blue was the colour of choice.
BEST wishes!
geo

I was very fortunate to get wrapped up with a group of shooters early on that were helping forge the small caliber world ahead back then. A heck of a great bunch of guys. Walt Berger talked me in to being his first dealer on the west coast just so I could get my hands on some of his 17 caliber bullets. Russ Lucas came into my shop and helped me start producing 14 caliber bullets, Frank Brakefield helped me build my first 12 caliber rifle and helped push the limits of the 14 caliber to new limits along with Blaine Eddie and Marty Kolbet.


I can't think of any other sport with so many great people that freely shared their time, knowledge and love for shooting.

[Extreme Accuracy]

Out of curiosity, what do your targets look like at that velocity?
Are they stable enough to make it all the way?

This is from last weekends testing on a new light weight 14 caliber bullet. I had posted it over on Saubier's website as they have members I've worked with in the past to help us test new bullet designs.
-------------

"Pat, I finally got a chance to do some testing on the 8.5 grain bullets here. Trying to get the weather and my schedule to align for some range testing has been a struggle.

Sadly my chronograph was not up to the task and it ate up a lot of my time trying to troubleshoot it. You could probably hear me cussing it from there…. ARRGGHH!!!!

I did a quick preliminary run with both IMR 4198 and Hodgdon 4198 to see how the 8.5 grain bullets held up for stability. Ran them in my 14/221 Walkers to get some info that might help you out too. Both of the test guns I used are 1 in 7 twist rates though so it won’t be an apple to apple comparison.

Both rigs showed great stability and decent grouping with the initial load of:
IMR 4198 = 16.2 grains , CCI BR4 primers, 8.5gr Extreme Accuracy Moly coated.
Hodgdon 4198 = 16.2 grains, CCI BR4 primers, 8.5 gr. Extreme Accuracy Moly Coated.

The chronograph started losing them and no longer reading as soon as I stepped above the 4700 fps range. The highest reading I could get was 4760 and it would only capture an occasional round. It was very frustrating to say the least.

Both rigs liked the Hodgdon H-4198 better for some strange reason. The IMR is usually the chosen powder in both of these test guns. Both also showed an improvement in accuracy as soon as I switched over to the CCI 450 small rifle magnum primers. Sadly the chronograph could not get a reading on those test rounds to let me know the speed range on them.

The primers and brass showed no signs of pressure and I was ready to step up the speed a bit but without a chronograph that would tell me where I was at I decided to wait until I have the strain gauge and laptop hooked up to them.

None of the bullets came apart even with a light rain starting to fall. With a 1 in 7 twist rate that put them well above the 480,000 rpm level. The J4 Jackets held up well and had zero failures. In the 1 in 9 twist 5000 fps should not be a problem from the RPM standpoint.

I’ll try to run them in the 14 Hornet Extreme and the 14 TCM Extreme on my next outing. It should give me both ends of the spectrum on the speed range.

Keep me posted on how you do with them and as always stay on target,

Carl C.

Extreme Accuracy"

[M-Tecs]

The small caliber HV crowd seems to hang out on http://www.saubier.com/forum/index.php

Give Hornady a call and ask for a ballistician. They might have some recommendations.

The fastest I have chrono'ed is 4,211 in 22 Cal. In the 80's I had fouling and bullet performance issues with the 17 Rem. I turned me off on the small cal. HV's. I do have a soft spot for the 204 Ruger but that is still way larger and slower than what you are playing with.

If you find a solution please keep us posted?

Are you having any fouling issues? How's the barrel life?

[country gent]

Maybe try doubling the screen spacing from 3' to 6'. At the speeds your running it may be faulting out. This should make the chrony think its 2350 fps. You will have to multiply the readings by 2 though.

[Extreme Accuracy]

The small caliber HV crowd seems to hang out on http://www.saubier.com/forum/index.php

Give Hornady a call and ask for a ballistician. They might have some recommendations.

The fastest I have chrono'ed is 4,211 in 22 Cal. In the 80's I have fouling and bullet performance issues with the 17 Rem. I turned me off on the small cal. HV's. I do have a soft spot for the 204 Ruger but that is still way larger and slower than what you are playing with.

If you find a solution please keep us posted?

Are you having any fouling issues? How's the barrel life?

Thankfully after moving away from shooting naked bullets in my high speed guns I haven't had to fight with barrel fouling for a long time. With the top notched barrels of today, better cleaning solvents and bullet coatings a LOT of the problems of yesterday have been seriously reduced. Un-fouling a small caliber barrel used to be a real nightmare back in the day.

Barrel life has been extended a great deal as well. I'm still shooting the very first 14 caliber barrel that Chris and Casey made at Pac-Nor barrels. Over the last 20 years it's had a lot of test rounds put through it and it has completed many, many varmint dispatches. I still have yet to have to pull the barrel and set the chamber forward on it after many thousands of rounds through it.

Pac-Nor's Super Match barrels with the 3 land heavy groove hold up REALLY well for me. I can't say enough about their barrels and Butches Bore shine. (I do wonder if the Butches bore shine of today is the same as Butches old recipe though.) I bought a large amount of it from Butch when he was selling it out of his garage well before he sold the recipe to Lyman. The new stuff seems to have changed a bit but that could just be from long term storage of the old lot.

I meet with Chris and Casey of Pac-Nor years ago at the shot show in Vegas and talked them into trying their hand at building 14 caliber barrels. I had been trying in vain to get one from Lawrence Rifle barrels for many years with no success. Chris and Casey stepped up for me and built in my opinion one of the best 14 caliber barrels the world has ever seen. I’m so glad that after the fire at their shop they decided to re-build and get back into business. I hope I can get them talked in to start building 14 caliber barrels again when things stabilize there. Out of the twenty 14 caliber barrels I bought from them I never had a lemon. With the tiny bore dimensions and barrel lengths I use that says a great deal about their quality control and their top notched barrel building abilities.


Carl C.
Extreme Accuracy

[M-Tecs]

What coating are you using? I am using Hexagonal Boron Nitride (HBN). I started Molybdenum Disulfide (Moly) and played a little with Tungsten Disulfide (Ws2 /DanZac) but settled on HBN.

The original Butch's Bore Shine per the MSDS's was identical to GM TOP engine cleaner. I can't speak about if BBS changed but the GM TOP engine cleaner was changed due to EPA requirements.

[Extreme Accuracy]

I’m back to using Moly as my primary high speed coating on my small calibers. I seem to consistently get better results over the Ws2 in my barrels. When I first looked into the HBN I was worried about the high thermal conductivity so I didn’t spend much time working with it. I had spent a lot of time dealing with core melt outs and bullet blow ups and didn’t want to go back down that path. I should revisit it with the new bullet core and jacket design and see how it does.

I know Butch had friends that worked in the refineries in Billings. I was pretty sure he was using some of their carbon deposit removers like Techcron in the batches he was making from the looks of things there. I’m sure if the EPA requirements changed it probably affected the Bore Shine recipe as well.

[Extreme Accuracy]

Follow up on 14 caliber testing:

The weather cleared and I got another chance to run the 8.5 grain bullets with IMR 4198 and Hodgdon 4198 in the 14/221 Walker today. I only ran them in 1 test rifle this time and again it’s a 1 in 7 twist rates so it won’t be an apple to apple comparison to the 1 in 9 twist rate barrels.

The bullets still showed great stability and pretty good grouping with a load of:

IMR 4198 = 16.6 grs, 16.8 grs and 17.0 grains , (5 shots each powder loading), CCI BR4 primers, 8.5 gr Extreme Accuracy Moly coated.

Hodgdon 4198 = 16.6, 16.8 grains, CCI BR4 primers, 8.5 gr. Extreme Accuracy Moly Coated.

The chronograph could not pick up any of the shots fired today. I think the bullet speeds are just way too fast for the CED Millennium chronograph. From running the loads in quick load they should be clocking in just over 4900 fps. (I normally find the quick load data to be pretty close on this test barrel.) Quick load predicted 4929 fps for the 17.0 grain load of IMR-4198.

The IMR-4198 stepped up its game today and did better on this round of testing then the Hodgdon-4198. All rounds were fired with CCI-BR4 primers. I’ll try to switch back over to the CCI-450 as soon as I get in the next accuracy node to see if it tunes in better.

(I did not get a chance to finish out the 17.0 grain load on the Hodgdon 4198 for this test.)

All of the bullets held together with no bullet blow ups even though they must have been clocking in at over 500,000 RPM’s. I’m very impressed with this core and jacket combo. Normally anything at or above a 15 grain bullet weight would have started to come apart already.

At the end of my test I ran 2 test rounds into 2 full soda cans to show a couple folks what they will do. Both cans turned into 2 flat sheets of aluminum foil with a lot of wet mist in the air. Both of the guys watching were pretty awestruck at the results.

I think I can even push these bullets in the 1 in 7 twist barrels up the 5000 fps range. I saw zero core melt outs and the holes in the paper were all perfectly cut. All primers and brass showed no signs of pressure at this point.


As always stay on target,

Carl C.

Extreme accuracy

[414gates]

I'd suggest using a 1/10,000 micrometer to compare case head expansion to virgin brass, as a method to determine maximum pressure.

Shoot through chronographs are not designed to measure those speeds.

Even the doppler radar types may not work because the base of the bullet is small to reliably deflect the signal back.

Seeing as you are not looking for a particular velocity, the better way to identify max loads is the the micrometer.

The method is described here

[M-Tecs]

Case head expansion is at its best when you have a factory cartridge of KNOWN pressure and an unfired case out of the same lot as the factory fired case you are using as a standard. That will give you a valid comparison. As soon as you switch headstamps it becomes meaningless. Lapua and LC tend to be on the harder side. Norma and Federal tend to be on the soft side. You will get significant different readings at the same pressure using different brands of brass. You even see it with the same headstamp brass but different lots. Learned that the hard way when I was into wildcats.

A blade mic is better suited for this application. The anvil on most standard mics is too large so they pick up the pressure ring not the case head. The straighter the case the more of an issue this becomes.

Since the OP doesn't have a factory case to use as the standard it will tell the OP little about pressures or velocities. Most of the people that I know that play with the high pressure/velocity game use primer pocket life to determine max. pressures. They tend to want to know the actual speed also.

County Gents suggestion of double spacing might work if the issues is not related to the projectile being too fast/small to trip the sensors.

In the old days they used momentum to calculate velocity fairly well. That MIGHT be an option?

https://www.shootingtimes.com/editor...tridges/371443
Case-head expansion (CHE) is supposedly a handloader’s way to “measure” pressures. Some practitioners even claim “X” amount of expansion means “Y” pounds per square inch; others claim it doesn’t mean much unless compared to CHE of known-pressure ammo, such as factory loads. Some people claim CHE works best on new cases, while others suggest once-fired cases. Many also disagree on exactly where to measure expansion on a case. (Most advocates for the CHE method usually don’t have access to a pressure lab, and that’s the reason they’re using CHE in the first place.)

To the OP I would give a call to https://oehler-research.com/system-89/ and see if they have any recommendations.

[TurnipEaterDown]

To tag onto post #19, re: case head expansion & pressure:

Measuring case head expansion is analogous to copper crusher pressure measurement. Measurement of permanent deformation to gain a reading on Peak pressure.
The CUP measurement system, while Much better than nothing for many decades before piezo pressure transducers, did have significant limitations. Several being: Only an estimate of peak pressure (no curve character), issues w/ peak pressure estimation w/ very sharp pressure rise rates, etc.
Look at tables of CUP vs PSI measurements on cartridges, and this will provide insight.

HOWEVER, when measuring case expansion with differences in brass hardness (with NO correlation curve provided between the measured hardness of brass and a Controlled Applied pressure, to correlate the deformation measured on case to a combustion pressure), variability of measurements taken (measure the same piece 10 times at 'the same location' to get an idea how 'good' your technique and tools are), variability of hardness at differing locations on the case, variability in hardness between manufacturer and manufacturer lot, Very small permanent offset changes indicating significant pressure change, etc. a person taking these measurements for granted is really being quite naive and (in a literal sense of the language) ignorant of what they are attempting to do.

There are some methods that people can use on high pressure (~60K psi) cartridges to stay within reasonable operating ranges in strong firearms, but these also require informed judgement and a willingness to accept risk. While many people use them (myself included, noting that I am not "special"...), I re-thought and chose not to type them out as someone could get a wrong impression and create undue risk.


On the determining velocity, yeah, call Oehler...
I know the 35P will measure 6mm 55gr bullets to 4500+ fps by experience, but that really isn't of much use to know. Very much different bullet size.

Using Momentum to calculate velocity: this was often an impact pendulum or pendulum trap from what I know. Maybe what is being envisioned?
I always thought of this as a energy capture device (kinetic to potential) rather than momentum, so maybe not envisioning the same thing.

With a small bullet at high speed, the friction in a pendulum bearing would need to be defined well and the displacement of the arm well measured (a person could rig a compounding linkage to magnify a pointer position) to get a useful estimate of velocity after calculation.
I suppose a person could construct a pendulum trap, shoot something well known & fairly "close" into it to measure the energy captured (peak rise known mass, calculate potential energy) and then create an offset / correction factor for energy lost in the bearing & work done / temperature rise as the bullet came apart in the pendulum trap.
I expect this idea I expounded on would be a bit crude though.