Chronograph Problems Redux

[BLTsandwedge]

Not too long ago I began a thread about a chronograph that I adjusted (to my great satisfaction) with two solid hits from a friend's FAA micro .22LR revolver. The adjustment worked well for a time- and all was good. This past weekend, the chronograph in question- I won't mention a brand name but it rhymes with Shmooting Schrony Shbeta Model- began a bizarre downward spiral toward uselessness.

Saturday's session started fine- I measured a reasonable string of .40s in the 850fps range- correct for the load type I was using. However, an hour into the session and after learning that a 452630 over 8g AA#5 would alternately produce velocities from 4,230 fps down to 227fps and back again, I had two thoughts- I had a bad batch of AA#5 or there was something wrong with my velocity measuring device. In further retrospect, I thought it unlikely that I could achieve 4,230fps with that particular .45acp load- evidenced by the lack of barrel leading, hard case extraction (a S&W 625 was used) or any other sign of high pressure. Ergo the chronograph. I already had a hate-hate relationship with that particular *** machine- I gave it to Mal Paso so he could drive his skip loader over it a few dozen times.

That bening done I'm without a chronograph and still hell-bent on creating my own reloading manual. I ask the forum for suggestions regarding what type/brand of chronograph to buy- knowing I don't want to evoke the ire of SWMBO in spending too much. Your suggestions are greatly appreciated.

Best regards,

Tom

[Rocky Raab]

If my Oehler 35P ever died, I'd look hard at a CED Millenium.

Don't take this wrong, but if I bought a reloading manual and learned that the data was gathered with a cheap chronograph, I'd treat that book the way you treated your Tooting Phony.

[mpmarty]

Wow! I've got a "cheap" Shooting Chrony and it does just fine with everything I throw over it. I've measured BBs from a daisy Red Ryder carbine and 12ga slugs from my Saiga 12. All readings seem quite plausible and are within my expected range(s). This is my second Shooting Chrony as my first one died when a friend shot it with his .40 S&W. Quite a penetration test.:killingpc

[mike in co]

what rocky said......


(krap i just agreed with a gun writer.....in public, in print.....chit...no quoting allowed.....)


mike in co

[mike in co]

there is a professional chrono out there..8-900 bucks from NECO.

[JIMinPHX]

I've gotten some really strange velocity reading variations from a chronograph when a gas check came off the back of a boolit in flight & double tripped one of the sensors. If you double trip the first sensor, you get a very high speed reading. If you double trip the second sensor, you get a slow reading.

That aside, I've been using the same shooting chrony for over 20 years with good results. I just recently bought new sky screens because the originals were getting cracked & yellowed from age. I've filled two loose leaf binders with targets that I documented with that instrument & it's still going strong. I'm sorry to hear that your experience with that tool was not as good as mine.

[d garfield]

Check your battery, that happen to me,

[beagle]

Yeah, I'd say check the battery and also see if anything is in the sensor ports. Sometimes that can haywire things./beagle

[emorris]

You may try backing away a few feet if you are not already not doing so. According to the manufacture on slower velocity loads the gases can effect the reading. I have confirmed this with my 9mm castplinking load clocking in between 7500 fps about two feet from muzzle and around 934 fps 10 feet from muzzle, with 3.2 grn of titegroup. Could you imagine a 9mm traveling that fast? You would have to shoot and then duck down. [smilie=6:

[10mmShooter]

My Master Beta Chrony...is sensitive, I can shot .38 and 44(950fps) rounds over it just fine at 10 ft...... But if I shot my warmer 10mm rounds 1100fps, i start to get goffy readings..backed it up to 15ft now for all caliber and works great.


I also use a half piece of poster board laying across the chrony rods....for consistency, no matter cloudly or sunny I always use the white poster board works great really elimnates random screwy readings.

[AbitNutz]

I have a CED M2 with infrared sky screens and rechargeable sky screen batteries. It works great. It down loads into my computer with no issues.

The most important thing you can add is a really decent tripod. I am not a camera guy so one tripod sounded pretty much like another. I bought a $30.00 tripod from Target..threw it away. Then found a Bogan with a Manfrotto ball head. I paid $120.00 for it and though that was crazy because that's almost what I had in in the chronograph. Trust me....it was worth every penny. The Bogen/Manfrotto combo cost upwards of $400.00 new so even though I was stupid, I was lucky. Even when you don't know what you're looking at you can see quality.

I then bought a Ransom rest with a windage tray. I bolted that to some rigid plywood with cross braces to Clamp it to the shooting benches.

The problem with all of this is that you must be prepared for any eventuality. Anything you forget, anything you break, ends up costing you an entire day. All this takes a great deal of logistics just packing, unpacking, setting up, making sure it is all correct and the shooting.

I have a checklist of everything I need to take and everything I want to accomplish.

Another problem is spectators wanting to talk to you...that really slows you down or causes you to make a mistake. I don't dare not speak, ignore or be rude to people. I just don't have it in me and this isn't the kind of sport that I ever wish to become known for or condones being less than unbelievably gracious and helpful . I tend to keep my ears on and look intense and most folks figure out you're busy.

Again, it looks like I didn't answer the question...only expanded it....sorry

[qajaq59]

When you check the batteries, clean the contacts as well.

[Mal Paso]

AbitNutz brought up something I hadn't thought of, Tripod Weight. Although it doesn't account for All the problems BLT was having, it's a good start. For obvious reasons BLT was using an inexpensive tripod. When I got started in Commercial Photography I used whatever I had until I could afford better. One way to increase stability was to hang Sandbags from the Centerpost of the Tripod. I think I'll reassemble BLTs Chrony and do an experiment to see. Last Saturday I had fewer errors with the Chrony I was using and I had a slightly heavier Bogen Tripod. We both had problems at the same time through the day which may be traced to Lighting and the Chrony's limited range but increasing the Mass would be a good start regardless of Chronograph Make.

[Larry Gibson]

My Master Beta Chrony...is sensitive, I can shot .38 and 44(950fps) rounds over it just fine at 10 ft...... But if I shot my warmer 10mm rounds 1100fps, i start to get goffy readings..backed it up to 15ft now for all caliber and works great.


I also use a half piece of poster board laying across the chrony rods....for consistency, no matter cloudly or sunny I always use the white poster board works great really elimnates random screwy readings.

That's the same lesson I learned a long time ago. 15 feet is my standard distance.

Larry Gibson

[Rocky Raab]

No sweat, Mike. I'm sure nobody noticed. But agreeing with a gun writer earns you one each freebie for future use. Here ya go ...

http://i27.photobucket.com/albums/c170/RockyRaab/GIF/BS_Flag_Product.jpg