Range Report Please check my work

[GhengisAhn175]

Gentlemen,

My post is concerning proper use and record of my velocities via chronograph. This is my first time ever using the system and recording velocities and I would like to know that I am doing it properly.

Below are the specs and ammo information

Chronograph: pro chronograph pal

ammo: loaded for my by southwest ammunition
.260 remington
139g scenars
lapua brass
42.0g of 4350
cci #200 primers
cartridge length 2.80 (this was given to me by the previous owner and said this load set up was the most accurate, but his records stated 2800 fps)

20 rounds were fired total
2737 / 2749 / 2677 / 2688 / 2650 / 2699 / 2688 / 2732 / 2710 / 2726 / 2732 / 2704 / 2677 / 2704 / 2721 / 2699 / 2754 / 2726 / 2682 / 2710
Average with all: 2708
average with highest and lowest record: 2702

rounds 1 and 2 were fired pretty close from barrel tip to chrono so I backed up to the 5-15 feet recommended (around 10ish feet, didnt do exact). all other rounds were around 10 ft tip to chrono

Couple questions from me:
1. Did I do this chrono record properly? Any improvements/sustains? I plan on continuing this record for the next 50ish rounds to see the consistency of the sw ammo.
2. Is it common to see the variances of speed from the rounds I have? Is this "company" standard or will personal reloading give me better results? (I am actually unsure if these results in variances are good, decent or bad)

I am not by any means knocking southwest ammo. They did well to build each round to my specifications although I cannot verify their work other than my shooting.

I did fire 10 additional rounds and at 100 meters, my groups never opened up past a dime. (5 shot, 5 shot, 5 shot, 5 shot, 10 shot). all 5 groups were within a dime diameter.

Thank you guys for your review, responses and time.

Very respectfully,

James

 

[KYpatriot]

It is important to chrono from the same distance each time. There us nothing "wrong" with the ammo, and it appears from your groups that the ammo agrees with your rifle...but I assume you are here to shoot long range, not groups. There is too much emphasis on groups i think you need good groups but unlike other disciplines good 100 yard groups are just the beginning...the ES (extreme spread) is very important.

To illustrate that, run your ballistic calculator out at 900 yards or so, one at the low velocity in your string and one at the high velocity of the string.

Also, while chrono graphs and other measuring tools will sometimes lie, the bullet cannot lie and is the arbiter of truth. It goes where it goes for a reason, and part of the discipline is figuring out what is lying to us...sometimes it is the scope (are those really 1/4 clicks), sometimes it is the chrony, sometimes range ambiguity, often it is our wind estimation or trigger control. The point is the only way to get good at shooting at range is to shoot at range, keep an open mind, and be objective about each shot.

So, your next post should be about whether the dope it took to get in target at range is in line with your expectations from your chronograph data, and if not why. Then we will be getting somewhere, as the chrony is only a small part of the puzzle.

 

[GhengisAhn175]

Thanks patriot! I'll sand bag down the chrono next range time (probably tomorrow). would you recommend one fixed distance or several from 5, 10, 15 ft? I will bust out the damn tape measure if I has to!

At this time, since I am new to precision shooting, I would like to continue working on my fundamentals (I printed out the 4 SH training dot sheets and the groups from my post were from the group ring sheet). I will continue with dot drills a couple times before I stretch out to the range here which has gongs from 100m to 1000m (I hope the distances are correct).

It's good to hear that the velocity range isn't abnormal. I would like to continue with SW ammo until I can get into reloading on my own.

Question about doping out to range. since there are only gongs here, should I count each hit as a general success or try to find means to set up paper targets out to distance and measure the hits at?

 

[KYpatriot]

You don't need the chrono at every range session. Once you have a starting point for your ballistics calculations, you will shoot at various ranges to figure out the dope you need to get real world hits.

It is always about the fundamentals of shooting, this site is very good about helping you in that area, there are lots of guys here can help answer your questions in that area, and it goes without saying that if you can get quality hands on training in person there I really no substitute for it. I won't attempt to go into what those fundamentals are, it is too much for one post and there are those here far more qualified to teach it than I.

Hits on the gongs are a good start, if you can get consistent hits you have a pretty good start on the dope. Record the environmentals and your dope in a logbook so you have a record.

Welcome to the hide and the awesome discipline of long range shooting. Part science, part machine, and a lot of art, there are few things that compare. Be patient, good consistent repeatable hits at reasonable ranges are better than Hail Marys and the occasional hit at extreme ranges. Try to learn from and analyze every shot, but don't forget to have fun!