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Discussion Starter #1
Hello all;
I'm new to this forum, and I thought I'd ask some questions of some experienced reloaders out there. I've been reloading for the past 20 years so I thought I knew what I was doing.
3006 - 150gr SP
50 gr IMR4895
CCI200 - Case R-P
1st load - case length 2.484
O.A. length 3.200 - 8/5/03
Av velocity:3367
Ext. spread:52.37
Standard Dev:20.49
I was suprized when I saw the speed on that load, but It extraced easily, but the primers were flattened and the load I shot before it with 51gr. of powder clocked at 2965fps and had an ES of 7.99 and SD of 5.65. So this looks strange to me, does it to you? What is going on with this load as the book max is about 51.5gr.?

Happy shooting.

Scott5
 

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The Hog Whisperer (Administrator)
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Two of my sources (Hodgdon/Speer) show around 49 grains max and one (Nosler) is 51gr. But none of them are over 3,000fps which suggests that the 51 gr. load is pretty hot so I wouldn't think of exceeding it.

Higher velocity = higher pressure. A good rule of thumb is that if you are exceeding velocities published in the manuals, you are over pressure, even if you are using less powder (assuming similar barrel lengths).

As far as a lighter load giving higher speed, there are several explanations for that. Mostly, our small group samples don't have enough data points to reliably say that we are in fact measuring the average. Even if we did in fact find the true average with one group, on the next group the small sample could have been given us an 'average' which only reflects some 'high' or some 'low' shots, not a true average.

On the other hand that's a whopping big jump in velocity which makes me suspect a chronograph problem, rather than just a statistical anomaly.

Suffice to say that statistics are a complex subject and I don't believe I can adequately explain them in a forum post, if at all.

Personally - I'd back the charge weights off a bit. And check the chrono with some other loads, preferrably factory loads of a known velocity (.22 target ammo is great for this).
 

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The Troll Whisperer (Moderator)
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First of all, Welcome to the board, Scott5 - !

Notice you're from the southwest. If you habitate the part of the southwest I'm from, the summertime temps are running in the 110 - 115 deg range lately. That means your chamber pressure is going to be substantially higher than more moderate times of the year. I've noticed a 200 fps jump in the same loadings from fall/winter/spring loads when shooting in the middle of summer. That's why I take frozen hand towels to the range in 12-pac coolers and keep the ammo boxes in the coolers until a few minutes before use. That allows the condensation on the cases to dry and the cartridges to have a slightly cool feel prior to inserting into the chamber. The towels get draped over the gun barrels to assist in more rapid cooling in the hot ambient air temps. When they become merely cool, I then drape the damp, cool towels around my neck and continue shooting.

Don't give up on the load you've developed - just wait 'til after the 1st of Nov to try it, if you don't want to try the frozen towel deal.
 

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Discussion Starter #4 (Edited)
3006 magnum

Mike G;
I was there with a friend and we shot Winchester .22s out of a Rem bolt action @1420 fps and
6mm remington
58gr V-max
42.6gr IMR4064
CCI 200 W-W case
cl=2.226 OAL=2.750
Av.=3511
ES.=126.4
SD.=38.47

then with 41.4gr IMR4064
Av.=3445
ES.=183.8
SD.=54

60gr HP
43.4gr. IMR4064
Av.=3622
Es.=64.84
Sd.=20.24
all 10 shots each.
then 357 Mag. then the 3006 Magnum.

I don't think it's the crony.
Oh by the way, I should explain that when I work up a load in the rifles I take a box of 20 shells and put one load in the first ten and the next load in the second ten.
But on this box of 20 we shot the higher charge first which for the 3006 was 51gr. IMR4064
Av.=2965fps
Es.=7.99
Sd.=5.65

The MILDER load of 50gr. IMR4064 was
Av.=3367fps
Es.=52.37
Sd.=20.49


Happy shooting.
Scott5
 

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Are you sure you didn't confuse your markings as to which load was with the greater powder charge? I grain of powder shouldn't make that much difference one way or the other. Being that you mention the brass type we can't blame it on that. It looks to me like you may have made a mistake at the bench, it happens to us all.
 

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The Hog Whisperer (Administrator)
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10 rounds is a pretty good start for meaningful statistics, a lot of people use 5 or even 3 and the SD figures are pretty meaningless, statistically speaking, with that few rounds. 10 would give me a lot more confidence, though.

Anyway.... hot ammo, hot barrel, wrong load.... something isn't correct, no doubt about it.

How far from the muzzle was the chronograph, and is there any possibility of the screens somehow getting moved closer together when you shoot, like the folding Chrony's or the like. How much change in the lighting was there (sun goes behind a cloud, etc.)?

Since it was all done at the range at the same time I'm inclined to think that it was a mistake at the loading bench, or very hot ammo as suggested.

That much powder and a little more will fit in the '06 case with no problem.

Can't think of anything else. Any possibility whatsoever of the wrong bullet getting loaded, or mag primers?

I would assume that you loaded all of these at once which would minimize the chances of accidentally getting the wrong powder.

Those ES and SD figures for the 6mm loads look pretty wild. I haven't chrono'd my 6mm so don't know if it is a common problem with that cartridge, but to me it suggests some possibility of faulty readings.

All I can suggest at this point is to re-test each of the loads, perhaps 5 rounds each, making sure the ammo is cool. Also a few factory rounds of .30-06 ammo both before and after might be warranted.
 

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Believe you started too hot. IMR shows 49.5 grains as maximum @ 50,000 CUP, and recommends reducing that charge weight by 10% to begin with. Nosler maxes at 51.0, Sierra at 50.4, Speer at 49.5 and Hodgdon at 49.0. In any case, I don't see the logic in starting with your heaviest loads. I thought the idea was to start low and work your way up while watching for signs of excess pressure.
 

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I have gotten screwy results when my Chrony was too close to the muzzle. Try moving it 5 feet further away.
 

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Discussion Starter #12
I'm sorry i havent gotten back to make a reply, lots going on, and doing honeydo's for mom, reloading for the 6mm.

lossking, you are right, my first post was the correct powder IMR 4895.
As for the powder charge, In pistols I start right in the middle and go up from there, In the 06 checking my load data from years ago in the 150gr. bullet that 50gr. IMR4895 is the standard amount.
I was told that my brass may be the problem, and when I checked my brass a little piece of the neck of one of the cases was missing. I found it in the chamber when I cleaned the gun.
Thanks for all the replys gentlemen, I will investigate the posibilities and keep you posted.
As for the 6mm, my brother owns the Rem 788 so I wont use it anymore, but since I bought a Rem 700 varmenter in 6mm on sale may I keep you posted on that load development?

Happy shooting.
scott5
 

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scott5,

MikeG and twillis are absolutely correct in that if your muzzle is too close to your crony your readings will be false. Your readings will be the gas velocity and not the projectile velocity.


nitro
 
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