IMR4350 vs. H4350 (Missed Coyote!!!)

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blauber

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Well, I missed one this evening at 300yds. Everything felt okay, had him in my crosshairs at 14X magnification, on the first milldot beneath the crosshair which "is" bang on at 300 yds. The .243 is zeroed at 200yds.

So, now I'm looking for answers. Could a 35 C swing in temperature cause me to miss at 300yds because of a velocity decrease? Lets say I was bang on at 30C at 300yds (when I sighted it in) and was hunting in -5 C today.

Just wondering as I might flip to a temp stable powder if so....Wil E Coyote had my number today.

Thanks,
 
I just ran some numbers on JBM, and it appears that a 300 fps change in velocity, (3000-2700) results in a difference of about 2" at 300 yards with a pointy .243/100 gr bullet and a 200 yard zero; so I doubt if that would take you off the coyote. You know though, shooting at a 300 yard target would tell you what's going on. A 300 fps drop in velocity would potentially effect barrel harmonics, and that might account for a wide shot from a sporter barrel more than actual drop.
 
Wind was gusty, maybe up to 30 km/h, but I was directly upwind of the coyote. There may have been a slightly L to R, but methinks negligible based on my position relative to the target. The bullet was travelling with the wind...

I have set-up against and with the wind when adjusting the scope and have never really had to deal with windage issues. I believe the burn rate of IMR 4350 is just slightly hotter than H4350.
 
The two powders are definitely not interchangeable.

As for the OP's question, it just depends on how you developed your load. If you worked up the load using charge weights that increased by 1% at a time, and selected a charge weight that had a similar POI as those on either side of it, then it's unlikely that a temperature swing would cause a change in POI. Lower velocity, perhaps, which would cause the bullet to drop a bit quicker than it did in the summer, but at least the POI would remain the same.
 
"Coyote fever was a factor...my breathing had the crosshairs move up-down 3 coyotes before I settled in!"

Why do we bother talking about wind, temperatures and powder?
 
Let me gets this straight:confused:. You missed a dog @ 300 ish yards, in the wind (no mention of laser ranging)....and its the powders fault?:sok2
 
H4831 said:
"Coyote fever was a factor...my breathing had the crosshairs move up-down 3 coyotes before I settled in!"

Why do we bother talking about wind, temperatures and powder?
Click to expand...

Okay, got the point. :cool: But I did settle in well, and shot one last week at 160 yds, no problem and others at 225 yds. I estimated the range, and paced it off afterwards-290 yds.

Whether a temp unstable powder could cause a velocity decrease significant enough to alter POI at long range...that's the question. I don't think 2" would make a heck of a difference but say that coyote was 450 yds. Is a temp stable powder going to (more) consistently hit the mark? Temp stable powder is on the market for a reason....could it be one like this?
 
You might have went through the hair and missed by a fraction,question two if you shoot at 1000 coyotes at 300 yard do you think you would miss some?
 
i would put the center of the scope crosshairs on the coyote at that distance and squeeeze the trigger.
 
blauber said:
Okay, got the point. :cool: But I did settle in well, and shot one last week at 160 yds, no problem and others at 225 yds. I estimated the range, and paced it off afterwards-290 yds.

Whether a temp unstable powder could cause a velocity decrease significant enough to alter POI at long range...that's the question. I don't think 2" would make a heck of a difference but say that coyote was 450 yds. Is a temp stable powder going to (more) consistently hit the mark? Temp stable powder is on the market for a reason....could it be one like this?
Click to expand...

Temperature stable powder is just an excuse. Powder burning rate changing with temperature means the difference between summer and winter. Not a difference of five degrees.
Wind at your back, difference in powder brand, etc, are just more excuses.
It is a very simple and easy matter to miss a coyote at 300 yards.
I would have just said I missed. Period. The coyote presented a good shot, but I missed.
It certainly doesn't lower your stature on CGN, or anywhere else, to simply say you missed.
In fact, I think many of us would think more of a person who simply stated they missed a shot and made no attempt to figure out a reason, other than themselves, for the miss.
 
H4831 said:
Temperature stable powder is just an excuse. Powder burning rate changing with temperature means the difference between summer and winter. Not a difference of five degrees.
Wind at your back, difference in powder brand, etc, are just more excuses.
It is a very simple and easy matter to miss a coyote at 300 yards.
I would have just said I missed. Period. The coyote presented a good shot, but I missed.
It certainly doesn't lower your stature on CGN, or anywhere else, to simply say you missed.
In fact, I think many of us would think more of a person who simply stated they missed a shot and made no attempt to figure out a reason, other than themselves, for the miss.
Click to expand...

For the record-I missed, plain and simple. The temperature difference was about 35 C (from + 30 C to -5 C). I'm simply trying to become a better hunter, that's it.
 
blauber said:
For the record-I missed, plain and simple. The temperature difference was about 35 C (from + 30 C to -5 C). I'm simply trying to become a better hunter, that's it.
Click to expand...

Next time shoot a couple sight-in shots at a target - zeros can drift somewhat and rifles POI can change over time and in different conditions. Could be that your rifle needs to be zeroed again. Maybe you bumped something. Maybe you just missed due to wind or shooter error. The only way to determine what's going on is to shoot the rifle. Anything else is just guessing and wasting time.
 
H4831 said:
"Coyote fever was a factor...my breathing had the crosshairs move up-down 3 coyotes before I settled in!"

Why do we bother talking about wind, temperatures and powder?
Click to expand...

There has never been a story that could not be enhanced.
Similarily, there has never been a missed opportunity that seemed more acceptable if there were a number (the more the better) reasons (excuses) to make the end result more palatable.

The difference between H4350 and IMR 4350 is another rational variable to explain how I missed that F@#$%^&*&*G bush dog.
 
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