XBR @ the Cactus

I'll tell ya what sportsfans, I've got another rear bag coming next week and after it gets here, I'll take some of my leftover loaded ammo from Sunday at the Cactus and shoot it over my Oehler 35 chronograph on a sunny, balmy day here in Utah. Then I will load up some ammo right there on the spot with the exact same setting from Phoenix on my Harrells and shoot it over the chrono. Then I will see what the Harrells is throwing for weight and punch that into the Chargemaster and shoot that ammo over the chrono. This test should show what the difference is in ammo loaded at 1500 foot elevation at 56 degrees in 100% humidity and ammo that is loaded at 4800 foot elevation at 56 degrees in 25% humidity with both thrown and weighed charges. I'll post my results when I git 'er done.
 
Thanks Joe.
I am with Joe and Lowell on the moisture on the powder. And changing the volume for a powder thrower. Lowell pointed this out to me.
Keep the bottle closed. If the forecast is for rain. Have more than one bottle.
After it drys up some. Switch bottles. Oh, yea. It worked for me. It was a total fluke. Started the morning with powder from the day before. It was raining. First group was terrible. Switched bottles. Wow. Tightened right up. Same charge. N133.
 
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Jackie

jackie schmidt said:
In was hoping there would be a lot more than that, considering the size of the match.

I guess shooters are just not comfortable enough with it yet.

I hope we get some temperatures close to 80 this week end. I am bound and determined I am going to make this stuff work.

I got a call from Gary Walters about an hour ago, he is at Tomball right now, and it is 82 degrees. He has his Rail Gun on the Bench. Maybe he will get some good warmer weather data for us ...........jackie
Click to expand...

Today 31.5/31.6 at almost 80 degrees F, produced an Average of 3430
Today 31.8/31.9 at almost 80 degrees F, produced an Average of 3485
Today 31.2/31.3 at almost 80 degrees F, produced an Average of 3415

These were for 5 shot groups. The 31.5/31.6 seemed to produce the best groups. 32.1 did not shoot well when the temps were lower. Have to do alot more testing.

GW
 
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Jackie
"In was hoping there would be a lot more than that, considering the size of the match.
I guess shooters are just not comfortable enough with it yet."


Jackie we would have had one more shooter if you could have fixed your Tug Boat and came yourself.
 
For what is it worth, Scharnhorst was using XBR and won the LV grand and 3rd in the 2-gun. He did say that his tuner saved him a couple of times.
I do know that Larry had not shot one round of XBR until he got to Phoenix on Wednesday. He figured one thing out pretty quick. Fill up the case with powder.
 
Rex

I would say that is a HUGE piece of information.

That little tidbit about his tuner probably perked up some ears as well........jackie
 
Tom

It's a shame when something like running a business gets in the way of the important things in life. But I have grown kids I have to support:D.........jackie
 
Joe/ thanks for all you do for the sport, all the help you have gladly given, the exoerience you have shared. When you speak (write) I suspect most of us will benefit....should we allow ourselves to be open to new/differing thoughts. Look forward to seing you at WWCCA on 3/21/ Chuck
 
thanks for tuning info

I'm grateful to have you guys share what works for you in regards to tuning & your observations with different powders and conditions,

It is not important to me whether or not your observations are proven scientifically. You could be completely off base on what causes the problems with loads, but the fact is you've discovered what it takes to keep the groups small on a regular basis.

You are looking at the information you have, ie humidity, temp altitude ect and making an adjustment to load that keeps you competitive. The reasoning being based on fact is not important. The fact that your adjustments give positive results is the interesting part.

Your adjustments may coincide with some as yet undetermined formula. the important fact is when you make your observations and your adjustments the groups stay small... A man could drive himself crazy trying to figure out exactly why it works and trying to prove it works for this reason or that.. for me it's good enough that it works..If shooting was as important to life as the healing arts I'm sure we could match the reasons to the result..as it is now the results are fine for me.

keep up the good shooting and sharing,,some scientist or researcher can figure out the reasons why..I'll keep learning from the guys with the small groups..

Kirk
 
Kirk Ethridge said:
I'm grateful to have you guys share what works for you in regards to tuning & your observations with different powders and conditions,

It is not important to me whether or not your observations are proven scientifically. You could be completely off base on what causes the problems with loads, but the fact is you've discovered what it takes to keep the groups small on a regular basis.

You are looking at the information you have, ie humidity, temp altitude ect and making an adjustment to load that keeps you competitive. The reasoning being based on fact is not important. The fact that your adjustments give positive results is the interesting part.

Your adjustments may coincide with some as yet undetermined formula. the important fact is when you make your observations and your adjustments the groups stay small... A man could drive himself crazy trying to figure out exactly why it works and trying to prove it works for this reason or that.. for me it's good enough that it works..If shooting was as important to life as the healing arts I'm sure we could match the reasons to the result..as it is now the results are fine for me.

keep up the good shooting and sharing,,some scientist or researcher can figure out the reasons why..I'll keep learning from the guys with the small groups..

Kirk
Click to expand...



Kirk,

The hard part in all of this discussion is determining what to do and when to do it. And for that, a little science must be used to seperate the conditions from the factors to get a sum. Unfortunately, this is hard to do and is probably the reason why there are so many opinions on the subject. It is a rare day when you can get weather in which humidity will change but not the temperature. Or temperature change but not humidity. Only a scientific approach, a little luck, and lots of patience will be able to make a distinction as to what is really happening and why. A lot of hastily drawn conclusions will otherwise be made combining the two elements but calling it result of one.
 
For anyone interested, I ran another test on XBR today. It was very interesting--at least if you're a ballistic nerd like me. If not, don't bore yourself with the remainder of this post.

I took my leftover ammo that I loaded on Sunday in the deluge at the Cactus and fired it for group and chronographed it too. It was loaded at 55 degrees and 100% humidity at 1630 foot elevation with 53 clicks of XBR. It was fired today at 65 degrees with 35% humidity at 4880 foot elevation. It clocked 3352 fps with a deviation of 9 fps. It shot very well for the windy conditions at the mouth of a canyon and I guessed it at a mid "one". I would say that if the conditions had been more civil, it would have shot every bit as small as it did in Phoenix.

So, with the same bullets, barrel, powder, primers, thrower, and setting of 53 clicks, I loaded up more ammo and fired it immediately after shooting the Cactus ammo. It clocked 3338 with a deviation of 2 fps. The group was still good given the conditions. It was probably a high "one".

Then I set up my Chargemaster and weighed what 53 clicks was throwing. In Phoenix, it was throwing 30.9 to 31.1 grains. Today, it threw 31.0 to 31.1.

Then I dropped down to 51.5 clicks and shot it. It gave a nice round group that seemed a little less wind sensitive and was around a mid "one". It clocked 3240 fps with a deviation of 11 fps.

Then for kicks, I took a different lot of XBR and threw 51.5 clicks with it and shot it. It was the best group of the day and clocked 3217 fps with a devation of 10 fps. Not too bad for lot to lot consistency with these two lots anyway.

So what does this mean? Well, I'm not sure. Except for the fact that ammo loaded 600 miles away in a totally different climate shot well at home too without much variation in accuracy attained or velocity measured. That being said, a load tuned for the conditions today did shoot better and it happened to be a charge that was backed down quite a bit from what worked in Phoenix on Sunday. But it was warmer today by ten degrees.

I guess it just goes to show that we still need to lug all the reloading equipment around to each match no matter what powder we use!:)

P.S. I would have brought all my targets home to measure them but they were too messy to bother with. The flys were out pretty thick today and they found some shelter from the wind on my target paper, and well, I couldn't resist!:eek::cool:
 
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