Oh, WoW !...That Fast,for Real..............QuickLoad Help

[35R]

Good Morning Peeps.... I am still scratching my head after a short trip to the range(Sorry,no pics) yesterday.

I had a couple of hours to kill before going to the office yesterday morning and decided to drive up to to the local range and play around with some .223Rem loads I'm working on. I also brought my 7mm-08 Vanguard to shoot the last 10 rounds I have left from my last batch. A conversation sprung out with the gentleman shooting next to me. As he was testing loads through a Chrony for his two sporterized Swedish Mausers. He offered to shoot my 7mm-08 through the Chrony to measure the velocity of my loads. I only had one left when he offered and went ahead and shot it thru.
I had always extrapolated the velocity using various manuals and came up with 2850-2900 fps for my load using 41.50 grs of H4895 and Nosler 120 BT seated at 2.840" in my 20" barrel Vanguard.

To my amazement the shot registered 3013 fps :shock: on the Chrony. Was it really going that fast? Can someone run this load through quickload for me? Or, if someone with experience shooting the 7mm-08 can you share some velocities.

Thanks..........Meanwhile I'll keep scratching my head....

Note to self:

I really need to buy me a Chrony........

 

[FOTIS]

Chrony probably on the fritz or not fully opened

Cartridge : 7 mm-08 Rem.
Bullet : .284, 120, Nosler BalTip 28120
Useable Case Capaci: 51.618 grain H2O = 3.352 cm³
Cartridge O.A.L. L6: 2.840 inch = 72.14 mm
Barrel Length : 20.0 inch = 508.0 mm
Powder : Hodgdon H4895

Predicted data by increasing and decreasing the given charge,
incremented in steps of 1.0% of nominal charge.
CAUTION: Figures exceed maximum and minimum recommended loads !

Step Fill. Charge Vel. Energy Pmax Pmuz Prop.Burnt B_Time
% % Grains fps ft.lbs psi psi % ms

-10.0 78 37.35 2489 1651 34536 9268 92.2 1.224
-09.0 79 37.77 2516 1686 35519 9391 92.7 1.210
-08.0 80 38.18 2542 1722 36529 9512 93.1 1.196
-07.0 81 38.60 2568 1758 37565 9631 93.6 1.182
-06.0 82 39.01 2595 1794 38629 9749 94.0 1.166
-05.0 83 39.43 2621 1831 39721 9864 94.5 1.150
-04.0 84 39.84 2647 1867 40842 9977 94.9 1.135
-03.0 85 40.26 2674 1905 41993 10088 95.3 1.120
-02.0 85 40.67 2700 1942 43175 10197 95.7 1.105
-01.0 86 41.09 2726 1980 44388 10304 96.0 1.090
+00.0 87 41.50 2752 2018 45634 10408 96.4 1.076
+01.0 88 41.92 2778 2057 46912 10510 96.7 1.062
+02.0 89 42.33 2804 2096 48225 10610 97.1 1.048
+03.0 90 42.75 2830 2135 49573 10706 97.4 1.035
+04.0 91 43.16 2856 2174 50958 10800 97.6 1.022
+05.0 92 43.58 2882 2214 52379 10892 97.9 1.008 ! Near Maximum !

Results caused by ± 10% powder lot-to-lot burning rate variation using nominal charge
Data for burning rate increased by 10% relative to nominal value:
+Ba 87 41.50 2889 2224 53809 10452 99.7 0.997 ! Near Maximum !
Data for burning rate decreased by 10% relative to nominal value:
-Ba 87 41.50 2577 1770 37690 9901 89.5 1.177

 

[SJB358]

Yup, I am with Fotis on this one. Probably not opened all the way. Or heck, it could have been the lighting surrounding the screens. Too hard to make a judgement off one shot..

 

[35R]

Thanks Fotis, this makes more sense.

The strange thing is that his loads were around where they suppossed to be, 140 grs traveling at around 2650 fps.

PS I forgot to mention he was not using the sky screens (if that matter)

 

[35R]

Fotis,

If it's not too much to ask would you run another load for me. Same rifle 42.00 grains VARGET w/ 130 gr SPEER SPBT seated at 2.800".

This one is very accurate out of my gun.

Thanks Again,

35R

 

[R Flowers]

" I really need to buy me a Chrony."

No, this is exactly why you should not buy a Chrony. They are simply unreliable. Sure, they are cheap, but they are so often wrong.

Save a little more money and buy a better unit, there are several better brands out there.

 

[RiverRider]

I have a .243 that gives me about 200 fps more than QuickLOAD and all the manuals say Ishould get. And yes, I use a Chrony. All my other rifles yield velocities in line with QL and the published data.

I have chronographed loads for other people and as often as not, the velocities seen are lower thn expected. I trust my Chrony. I have, however, seen velocity readings that I know are not right when the sun is low on the horizon.

 

[RiverRider]

I forgot to mention that I have found that a Chrony has to be placed at least about 15 feet in front of the firing line or readings can be affected by muzzle blast.

 

[Guest]

" I really need to buy me a Chrony."

No, this is exactly why you should not buy a Chrony. They are simply unreliable. Sure, they are cheap, but they are so often wrong.

Save a little more money and buy a better unit, there are several better brands out there.

I'll disagree a bit here. I own a Beta Master Chrony and PACT Professional. The PACT hasn't seen the light of day in over 5yrs. Why? Because the two chronographs, when "piggybacked" (literally, using zip ties to attache the BMC to the PACT mounting bar, in between the PACT sky screens) gave similar readings, so either they are both right, or both junk in the same pattern. Those readings were shots ranging from 30-30WCF to 270Wby in velocity, with a 243Win and 8x57 in between. The keys to using a chrony are pretty simple:

Place it at least 15' from the muzzle.

Be sure it's fully unfolded and "locked" into place.

Be sure you don't shoot it, but just shoot through it.

Keep a notebook of your data written in pencil (because ink runs when it gets wet.

You can certainly save up and buy a more expensive unit from another manufacturer. But for me, the hassle factor has been reduced so much, and the reliability (and consistency from one range session to another) has been so good, I'm sticking with the BMC.

I will add that you should definitely get one of the "Master" series, with the display sitting on the bench, rather than in the unit out at 15'. Much better for long range sessions. Oh, and get a sturdy tripod. And keep spiders from drifting silk onto your skyscreens. I got 4100fps from a 180gr in a 300Wby once due to spider silk!

 

[DrMike]

I've used two Beta Master Chronys for the pasts seven years. They have performed quite well, and given me no cause for distress. I have an Oehler coming in a couple of weeks. I don't know that my data will be any better than it has been, but it will certainly be more professional looking.

 

[kraky1]

Interesting......and I'm chuckling to myself. As I started to read the post I saw the caliber and said.....I wonder if we're gonna have a H4895 situation.
This past summer I played with H4895 and I 4895 in my 3006 trying to find a fast accurate 110 vmax load. Around 59 grains seemed to be max data I was finding and looked acceptable to quickload.
So I go to the range with 59 of both powders in identical brass.
First up was I4895....speed right where I thought it would be...3390.
Next up h4895....wholy crap....3550 fps.
When I got home I re-ran quickload and it thought that it would take almost 66 grains to crank 3550 with h4895.
I've had this batch for quite a while and in milder loads it doesn't seem to go wild. But i can only conclude that as I approach max loads the h4895 gets really active.
I don't know what else to say except I believe you had a speedy encounter and what you saw was legitimate.
If you go to the hodgdon website and look at what they show for I4895 and h4895 loads they definately show h4895 is hotter and I've seen in their data at times they want you to use up to 3 grains less than I4895.

 

[DrMike]

Good point, kraky1. It is easy to forget when reviewing data that burn rates change as bullet weight and case volume changes. Sometimes, those differences in burn rate can be quite dramatic. Again, a really good reminded to start low and work up on any change.

 

[FOTIS]

" I really need to buy me a Chrony."

No, this is exactly why you should not buy a Chrony. They are simply unreliable. Sure, they are cheap, but they are so often wrong.

Save a little more money and buy a better unit, there are several better brands out there.

Expensive but the best. :!:

 

[FOTIS]

I can see 100 or maybe 200 fps difference but not 400 fps. No way no how!

 

[35R]

Thanks everyone for your comments. And I agree, 350 fps difference is a lot. I've never thought for a second this combo would shoot that fast. Again, the guy's loads were all right there at "normal" 6.5x55 speeds with 140 grains bullets. Too bad I was on my last round when he offered. I would had like to had shot at least two or three more rounds through it.

I think I'll add a good Chrono to the other wish list thread :mrgreen: Perhaps, that Oehler 35P :lol: