Chronograph for small caliber high speed bullets???
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
Todd was the one who talked me into building my first 20 Tactical back in the day.
Quote:
Originally Posted by
georgerkahn
"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.
Stability on the newly designed light weight bullet has been very good so far.
Quote:
Originally Posted by
577450
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.
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"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"
2 Attachment(s)
Here's a pick of the development loads.
Quote:
Originally Posted by
577450
I might be missing something. I asked what kind of accuracy and the closest answer was "pretty good" . Is the object high velocity or'extreme accuracy'? I'm probably just a dumb redneck- or bubba- if you prefer, but would 1 minute, 3 minutes , or 100 minutes be too hard to say? I don't know what a Saubier is so that didn't help. John
These tests are trying to determine bullet stability in the high speed twist 14 caliber barrels (1 in 7 twist). The accuracy will need tweeked in after I find the speed range of the bullets. As I run up the ladder test these loads showed "pretty good" results in that speed range. As the bullets top over the 5000 fps range I will start tweaking in the load for better accuracy. These bullets are actually for the 1 in 9 twist barrels which should show better accuracy when the RPM level is back in the sweet spot.
This testing is more for finding when the jackets start to fail.
They should look better without the bore cleaning round fired in the groups as well when testing is over.
Attachment 311152
Attachment 311151