I have been reloading for about a year with good results on paper for a 257 weatherby and 243. I bought a 7wsm and reloaded for it,sighted it in at 200yds and was very impressed. I decided since i went all out on the rifle I would buy a chrony and check velocities. 7 shots(it got dark) 2850 2866 2880 2861 2901 2895 2900. This doesnt seem very good to me even though on paper i could hit the 1 inch circle everytime not all touching but in the circle.My question i guess is what velocity range should i be expecting

From my experience anything in the range of 50fps is great. There are a lot of factors that can effect the velocities. Were they all the same head stamp on the brass. Were they all the same case length, the same crimp ect...

i'm corn fuzed

what are you trying to accomplish?

if you're loading to hunt and shooting
1 moa call it done

51fps Extreme Spread is not that bad but not great. Were those shot from a freshly cleaned barrel? How close were you measuring the powder charge? Some rounds sitting in a hot chamber longer than others between shots can also increase velocity some.

Best I ever have measured with my reloads is 7fps ES for 10 shots and that was carefully weighing each charge and having weight sorted the brass.

all were the same lengths and same brand. I do notice that with my digital scale i use i can put 4 to 5 granules of powder in before it moves to the next weight.

i know what you mean maximum. I have no concern at 200 but i didnt know what it would do at long ranges.

You might be onto something with your scale.

Kmon. yes it was a clean barrel and i actually told my son when we were shooting that it seemed that when the bullet sat in the gun longer it was the faster ones.

Yeah i just figured this out as im online. when i went digital i just would here the beep confirm weight and dump the powder. When messing with it the shortcut powder i can pull 8 granules out before it changes. I believe i will set my target weight low and then trickle the last until it changes

Some powders work much better than others. Here's an example: I am loading a 95-grain Partition in 6mm-284. When I was trying out Ramshot Magnum for this application, extreme spreads in 3-shot groups ran anywhere from 20 to 70 fps. When I switched to H4831SC, the extreme spreads in 5-shot groups is typically about 15 fps.

Primers might make a difference also. Ignition is a critical factor in ammunition performance.

Another thing to consider is the whole idea behind the Ladder Theory (which I do not use in load development, but is worthy of consideration for other purposes as well). If your using a powder that must be weighed out to within .02 grain to get good results at the charge levels you want to work with, then maybe you should be using another powder all together. The idea of the Ladder Theory is to find a sweet spot where small charge weight variations make the least difference. Just something to ponder...

I have a tendency to be overly anal at times when weighing charges, and one method I have resorted to in order to hold variations down is to put a charge on my digital scale that is a tenth or two light, and drop one or two kernels at a time into the pan until the target weight is displayed. That really runs counter to the ideas put forth in the Ladder Theory in terms of powder selection and charge weight selection, but hey---that's what being anal is all about!

If your shot groups every time..it's just numbers..I've had shot
strings that were 4fps spread that didn't group that well and some that w/20 or more fps that did...Expect somewhat slower velocitys in Texas than the books because of altitude..generally.
My 22-250 however shoots 3810 on a load that the book has as 3660
or so..Groups, projectiles and shot placement..We have a Chrony
and rarely use it and I have a range finder I intentionally play
with occasionally..but do not usually use hunting..Mostly TOYS and are not generally needed..DD

Most of my accuracy node loads will shoot in the 10 to 25 fps ES range. Sometimes when you are out of your node it will vary by 25 to 50 fps. But 2 things- you need a good chrono and must have accurate powder throws. The chrono at dusk is the worst time to check speeds because of the amount of light and the lighting angle. I use infrared skyscreens on my chrono when it starts getting dusk and can pick up bullets in pitch dark. The powder charge will influence the fps and if it varies by a .1 or more, then so will your fps. I load to .02 grains accuracy, which is about 1 kernel of extruded gun powder. If you are using 4831SC, then 1 kernel weighs about .03 grains, so 3 kernels should egual .1 grain.

Also, don't let the round "cook" in the chamber. Extract a fired shot ASAP, and chamber the round seconds before you pull the trigger. This way you can eliminate as many other variables as possible.

thanks for the help everyone. i wont get to shoot till next week but im going to trickle my powder and be more precise and wont leave a round cooking too long. I got this load data from a friend and while it groups well i think im gonna try to get more from the gun.

if you stay in the reload biz,
you need to invest in some
scale check weights.
cheap insurance bud. . . .

you may want to borrow a
known accurate beam scale
to cross check your electronic.

call me old fashioned. but i
still use my 10-10 and ancient
lyman. the batteries last longer.

how much does the high temp affect velocity?

Quite a bit. Leave your bullets out in the hot sun and it will cause higher pressures. That equates to more velocity.

Not exactly a safe thing to do if you are loading for max pressure to begin with.

Also s cheap scale weight would be a match bullet of known weight. I always keep a couple of match bullets near my scales to zero them out. If sierra says their SMK is 77 grns you can bank on it being 77 grns. So I set my scale to 77 grns, zero it up with the foot then I set it to the powder setting I want to throw and get to work.

That also depends on the powder, the Temp stable powders like Hodgdon Extreme powders are less affected by temp than some of the other powders. But they are still affected some by temps.

I had a buddy blow up his TRG 42 in 300 Win Mag shooting in 95 degree temps on a sunny afternoon. He ran a hot load, and I told him it was a hot load. But in his words, "But it shoots so good!". He left the ammo in the direct sunlight for over an hour. They were shooting at 400 yards, and moved back to 500, first shot, kaboom. Ballooned the barrel at the chamber just like Elmer Fud would in a Bugs Bunny cartoon. He was using R22, which will vary some with temps. But add the high temps, ammo in direct sunlight, and a hot load, and there you go! This is why I like to keep my ammo in a small cooler with a cold pack in it for long range sessions.

Rule of thumb on ball powders, is about 1 fps per degree. So if the ammo runs 2700 fps in 50 degrees, it should be 2750 fps on a 100 degree day. With an extreme powder like Hodgdon's, it's .3 to .7 fps per degree, with most in the .5 area.

In the early 60's when I first started reloading and got serious
about accuracy from a bench I shot w/my good buddy Bob Williams
in Alto who really got me into loading..He was BR shooting his
22-250 at a meet and left the loads on the bench on a hot day and
his primers ect were popping out...Heat affects/effects everything to do w/shooting more so than cold..Thats also why if
you read about our guys in the "stans" their guns get hot/fouled
and jam up when in a major fire fight..DD

Yes! Heat and moisture will spike pressures. It's interesting at a shooting match when it starts to rain and ammo gets wet. You start seeing guys piercing and blowing primers and locking up bolts. Those hot loads become extreme over pressure fast in harsh shooting consitions. This is why I don't run overly hot ammo.

I still use my balance beam scales if only loading a box or so
of ammo..but I have an elec scale and trickler if I am loading
100 rounds which is not unusual..But when I'm doing short trips
to the range, working or loads ect..I usually use the balance beam scales..The other is a bit of an investment, I think about
$250 or more..DD

I think your trust in balance beam scales is well placed, Don.

I have been using a pair of electronic scales for a couple of years now, the oldest one having been on my bench for nearly twenty years and which has earned my trust. I am using a Hornady dispenser now and the charges it dumps go right to the old reliable digital scale and so so far nothing odd has turned up. But for a guy who still wants to use a balance beam I would suggest the idea of using electronic scales for their speed, and then when you're ready to verify then dump the charges on the balance beam. Chances are the charges will come up aces every time and you will be able to move along at quite a good clip.

I also agree with the trust in a balance beam. I threw away one digital scale I got in a trade when I figured how inaccurate it was.

Like RR I am also a convert to the Hornady despenser, but I still check/verify with the balance beam scale

I have the 3rd Model Lyman also..and if I am loading a 100 rounds
or more, I'll spend the 30 minutes letting it warm up ect...But if I'm just going to load 20 rounds..the old reliable RCBS gets the nod..and i've got two of them..so I can check...Also I keep a
rather large piece of marble for a table to run the scales on if
loading much...It's not much of a hassel, but it usually pays off
in the end results..As to chrono..I had a 40X Rem 300 win Mag w/
a Rem. factory installed Hart bbl..and it shot..usually about a
4 fps spread on the crony..but the rifle was not particular..Others all differ...Some are close to the books & others are not..I mainly look for groups..because some of this stuff tends to be oversold..Don