First Range Report with Chrony

[jwrowland77]

First Range Report with Chronograph

Well, after almost going on 2 years of reloading I finally shot my loads of a chrony.

I just kind of want some feedback as to how my reloads are looking.

.308 155gr SMK Palma IMR4895 44.5gr (FTR 600yd Match Load)

Min 2710 Max 2799 Avg 2750 S-D 22 ES 89 (18 rounds)
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7mm RM Hornady BTSP 139gr IMR4350 57gr (I have worked up to 62gr, thinking about going to this load),(Hunting Load)

Min 2793 Max 2875 Avg 2836 S-D 25 ES 82 (9 rounds)
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Daughters .223 Nosler Partition 60gr H4895 24.5gr (Super accurate Hunting Load)

Min 2981 Max 3069 Avg 3015 S-D 26 ES 88 (14 rounds)
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Just kind of wondering if I'm where I should be for this stage in the game. Don't do anything but normal case prep. Use the electronic scale that came with my Hornady LnL Classic SS.

Thanks in advance for any advice to tighten these up. Open to any and all advice.

 

[mokin]

The standard deviation looks good. Better than most factory loads. How does it feel for you. Are you happy with the results? It was kind of an eye opener for me to see what the loads were really doing versus what my manuals said they should be doing. Best part of all is that you didn't shoot the chronograph. Keep in mind though that you can trim the tips of 1/4" dowels to fit the holes in you chrony if "accidents" occur....

 

[jwrowland77]

The standard deviation looks good. Better than most factory loads. How does it feel for you. Are you happy with the results? It was kind of an eye opener for me to see what the loads were really doing versus what my manuals said they should be doing. Best part of all is that you didn't shoot the chronograph. Keep in mind though that you can trim the tips of 1/4" dowels to fit the holes in you chrony if "accidents" occur....

Felt great. Happy with the velocities, since they were close to what I was guessing anyways. Very accurate loads.

 

[Andrew Leigh]

When I get to the "sweet spot" of my loads I expect to get std deviations of 12fps or less, happy when they are down at sun 8fps. This for 6.5mm to .375. Extreme spreads of 80fps would affect accuracy.

Without being too pedantic with case prep there are some gains to be had.
- The first would be to apply some statistical analysis to cases. I reject all outside 1std deviation. This means that on average I cull 15 of each batch of 50 Remington cases. Weigh your cases, record the weights and the order that you weighed them, calculate the mean and then 1 std deviation. Then go back and reject all that fall outside the range, + 0r -
- Seating has probably been responsible for many inconsistencies. I now seat very carefully, really feeling the bullet into the case. I am planning to buy an Arbor Press with gauge when funds become available.
- It costs little to buy a flash hole uniformer and just take a little time. You got nothing to lose. Does it make a difference? Why take the chance?
- I have also found that when shooting too low over a Chrony that results appear more erratic. I have a Beta Chrony and position it at least 7 yds from the barrel (made up my own cord, Chrony say one can go to 10yds). At this position the cross hairs are just under two thirds from the top of the screens which means that the bullet is passing just over half the way up. Don't forget that the barrel is about 1.6" below the scope line of sight at that point.

Good luck

 

[witchhunter]

Order some new sky screen supports right away, everyone I know has shot theirs...best be prepared so you can finish the day!!

 

[jwrowland77]

There's practically no way that I'll shoot my chrony or screen supports. I bought a MagnetoSpeed that attaches right to the barrel.

 

[556by45guy]

That explains the confusion and why some said to not shoot it, LOL. "Chrony" is a specific brand.

 

[jwrowland77]

Ah ok. My bad. I was just saying chrony for short for chronograph. Ooopppsss...lol. Sorry y'all for any confusion.

Changed title.

 

[popper]

Notice the SD & ES were all almost the same? That unit has some adjustable trigger settings I'd play with. That S-D shouldn't make any diff except at longer ranges (match shooting). +/- 12 fps? I don't do any special prep, ES is ~ +/- 20fps and still do MOA @ 100.

 

[dubbleA]

.308 155gr SMK Palma IMR4895 44.5gr (FTR 600yd Match Load)

Min 2710 Max 2799 Avg 2750 S-D 22 ES 89 (18 rounds)

I would certainly try to get the SD in the single digits for a match load. You are pushing 100fps extreme spread which not good at 600yds

 

[Hondo 60]

Your ES & SD seem to be fine.

As I always say:
There ain't but 2 kinds of chronograph users...
1. Them that's shot theirs
2. Them that's gonna shoot theirs.

I'll admit, I'm in the first category.
Scoped rifles are the bane of a chronograph's existence.

 

[kelbro]

Watch the tension on the strap or you might shoot yours.

 

[Captain Capsize]

Regarding replacing the aluminum sky screen posts after an "accident". Hitting one of the aluminum posts will usually wreck the block that the posts plug in to. It is a good idea to use wooden dowels right from the beginning and put away the aluminum ones. At least the wood ones will break without hurting the chronograph.