Just ordered a chrony.

[USMA-1982]

Ready to start work on performance upgrades to my 2240 mod and my 2400KT.  Took advantage of PA's memorial day discount code and ordered the Competition Electronics ProChrono Digital Chronograph and USB interface.  It doesn't seem to make sense to start adding Boss valves, etc until I establish a baseline performance. 

Sighted in the scope on my 2400KT.  I started at 25, but moved in a bit and it's now zeroed at 20 yards.  That seems about right for any trespassing starlings.  Parallax does not seem to be an issue as long as I have a consistent hold.  I did notice about 1 in every 6-8 shots were flyers, firing from a sandbag on a bench.  I was shooting 14.3 gr Benjamin Discovery PCP domed hollow points.  Anyone notice any issues with these pellets, or was it just me :-)  Except for the fliers it was grouping about 1.5" at 20 yards.  I can probably get tighter groups with a more stable shooting bench though.  I had jerry-rigged one for today so as not to waste the good weather.  I'll be working on a real bench next. 

Also shot the 2240 mod with the UltraDot for the first time today - many pinecones were destroyed!  Just did a quick zero at 5 yards for the UltraDot as it was getting late and I wanted to do some plinking before firing up the grill for dinner.  Adding the forearm and 10 in barrel makes for pretty accurate shooting inside 10 yards using a slightly modified Weaver hold.

All in all, a good first outing with the two new Crosmans.

[bgmcgee]

I bought one of those discovery packs of pellets they sell at walleyworld and I'm not to impressed with any of the pellets in it. The dome ones look to be the same as the Crosman brown box domes and the hollow points look just like the cphp hollow points. Neither one of my pistols like them.  In fact the pointed ones were so bad out of my S&W 78g that I missed my trap completely at 5 meters, which never happened before.

[Colt25]

Have fun with your chrony! I sure do!

[WyoMan]

I've had bad luck with the .22 14.3's.......some have said the .22 barrel is oversize and likes a larger head size
Maybe only true in part, if shooting with 2000 + psi that might obturate the pellet 
I use JSB 5.52mm and have no fliers but I check for dented skirts first
Good to get a chrony 

[Trophyhunter49]

  You will enjoy your chrony,I have really enjoyed mine

[agninja]

I was jacking around with my chrony the other day, shooting blowdarts through it. 96 fps!

[crossliner]

I was jacking around with my chrony the other day, shooting blowdarts through it. 96 fps!

How long is your blowgun, the caliber and what darts were you using? 96 fps is too slow.

[agninja]

How long is your blowgun, the caliber and what darts were you using? 96 fps is too slow.

It's a three footer with standard practice darts. It was weird, like I said I was just jacking around. My first shot was 96 fps, then I tried to blow harder on my second one and it was like 150, then I did another and it was exactly 96 fps again. So I figured that was a truer number. But I'm sure I wasn't blowing hard enough, as I've not really used the blowgun in a long time and I'm sure my technique is poor. What kind of numbers should a three footer be putting up?

[crossliner]

It's a three footer with standard practice darts. It was weird, like I said I was just jacking around. My first shot was 96 fps, then I tried to blow harder on my second one and it was like 150, then I did another and it was exactly 96 fps again. So I figured that was a truer number. But I'm sure I wasn't blowing hard enough, as I've not really used the blowgun in a long time and I'm sure my technique is poor. What kind of numbers should a three footer be putting up?

Well sir that should be about right for a 3 foot blowpipe using commercial target darts as they are loose and yes it's all about technique I agree..A fifty caliber should give you higher numbers especially if you are using a TargetZone Close Tolerance .50 brand..I would assume yours is a .40..I can do more than 250 fps w/ a .55 caliber four and a half foot blowgun using carbon fiber rod shafts w/ vinyl cone tail end 1.87 gram darts..

http://www.blowgun.com/shop/item.aspx?itemid=26


Sorry for the OT gents. Best regards.

[arkmaker †]

Good strategy, getting a baseline first. The chrome really helps tweak these  guns 

[Gareth]

I've been using a Chrony F1.

Ballistics is a fascinating subject. 

[Colt25]

I've been using a Chrony F1.

Ballistics is a fascinating subject. 

Very

You also need to look at this: http://www.hawkeoptics.com/chairgun.hthttp://www.youtube.com/watch?v=LgbWu8zJuboml

Remember, this software is only as good as the numbers you out into it 

[agninja]

Anyone ever put their chrony at the target, instead of at the muzzle, at a longer distance like 30 yards? I suppose you could calculate the estimated fpe if you know where it's at from the muzzle, but I bet a lot of people would be disappointed to realize that they are only delivering like 4 fpe once the pellet finally hits its target. 

[Colt25]

Anyone ever put their chrony at the target, instead of at the muzzle, at a longer distance like 30 yards? I suppose you could calculate the estimated fpe if you know where it's at from the muzzle, but I bet a lot of people would be disappointed to realize that they are only delivering like 4 fpe once the pellet finally hits its target. 

Yes, that is how you calculate ballistic coefficient. You chrony the muzzle velocity then out at at say 30 yards, and you can calculate BC from those numbers.

Hawke Chairgun pro has BC calculators.

[agninja]

Yes, that is how you calculate ballistic coefficient. You chrony the muzzle velocity then out at at say 30 yards, and you can calculate BC from those numbers.

Hawke Chairgun pro has BC calculators.

I'd assume if you know the muzzle velocity and pellet weight then you could just do the trig to calculate the rest. No need to put the chrony at risk if you get a low flyer at 30 yards.