Comparison of the ballistic superiority of 6.5 CM

[doctnj]

I found my number today to be 39.5. I already reloaded to that load and will do a verification shoot tomorrow. Wound up just below book max. I dont know. I felt I am an adult and understand the risks of shooting a load over book max. My 11 year old daughter does not. She shouldnt even have to consider that consequence at this point. So I worked up several loads and believe I found a laser beam. I personally do what he did, or close to it, but in 5 shot groups because I think 5 shows a real tendency of a shot. If you yank one shot out of 3 that is a third of your data that now cant be considered.

One point of interest. I shot a particular load on the low side. 5 of them were just for sighting in. Then I had an additional 5 that was suppose to be in the test as well. The sighters were close enough to the bull that I changed nothing. But they were spread out maybe and inch tall and inch and half wide edge to edge. I was concentrating a lot on these shots so I threw that load out of the test immediately. So after I finished the test and the rifle still very hot from the last string being fired. I loaded the remaining 5 rounds and rapid fired them. 4 out of 5 were in the bull all touching. This wasnt the load I selected. The load I selected only had three shots to it. That part makes me doubt it. See I yanked one and am going of the two that are nearly through the same hole. But the third is close by and on the same horizontal and the remaining two.

Its a factory sporter type barrel. Could the heat have played that big a part in the difference between the first and last group?

After I go for verification shoot tomorrow Ill post pics of both targets. The "guess" and the confirmation of being stupid or lucky. lol

[LongRange]

LR keeps sharing all the secrets I share with him lol!



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great secrets too LOL!!


I found my number today to be 39.5. I already reloaded to that load and will do a verification shoot tomorrow. Wound up just below book max. I dont know. I felt I am an adult and understand the risks of shooting a load over book max. My 11 year old daughter does not. She shouldnt even have to consider that consequence at this point. So I worked up several loads and believe I found a laser beam. I personally do what he did, or close to it, but in 5 shot groups because I think 5 shows a real tendency of a shot. If you yank one shot out of 3 that is a third of your data that now cant be considered.

One point of interest. I shot a particular load on the low side. 5 of them were just for sighting in. Then I had an additional 5 that was suppose to be in the test as well. The sighters were close enough to the bull that I changed nothing. But they were spread out maybe and inch tall and inch and half wide edge to edge. I was concentrating a lot on these shots so I threw that load out of the test immediately. So after I finished the test and the rifle still very hot from the last string being fired. I loaded the remaining 5 rounds and rapid fired them. 4 out of 5 were in the bull all touching. This wasnt the load I selected. The load I selected only had three shots to it. That part makes me doubt it. See I yanked one and am going of the two that are nearly through the same hole. But the third is close by and on the same horizontal and the remaining two.

Its a factory sporter type barrel. Could the heat have played that big a part in the difference between the first and last group?

After I go for verification shoot tomorrow Ill post pics of both targets. The "guess" and the confirmation of being stupid or lucky. lol

when you and the family go shoot are you guys shooting for groups or shooting to hit targets at different distances?
i only ask to remind you LOL!!

everyone has an opinion on how many shots should be fired during load development....most ppl say 5...bench rest and F-class guys say 10 to 20...you say you think shooting 5 shots per charge weight is better because if your shooting 3 and pull one a 3rd of your data is no good...well if you cant shoot 3 rounds without pulling one how can you shoot 5 without pulling one? and even if you shoot 5 rounds but pull one isnt that a 5th of your data thats no good now and youve come to the same conclusion that youll need to shoot it again to verify?

keep in mind your shooting a 243 that has a pretty short barrel life to begin with and yesterday you shot X amount of 5 shot groups and today will go out and shoot X amount of 5 shot groups to verify...(not being a dick we have talked and you know im just being straight)...but are you capable of shooting 5 shot one hole groups consistently? most ppl are not!

i do agree that more rounds are a better indication of consistency but i also know that with every round that goes through the same hole the pressure to put the next one in the same hole builds...and yes heat could be a part of the last group...but the bigger part is most likely the shooter thinking that was a crappy load so there was no pressure or expectations when he shot the last of those rounds...also keep in mind its a factory sporter barrel so dont expect bench rest accuracy from it.

[doctnj]

I was looking at the loads people were discussing over 40 gr on the 6mm and I didnt see many if any referring to 243 win. Ill see how it flies today. And to the 3, 5 thing. yeay pulling a shot screws thing up. One reason it was easy to do here is I left all of her but stock adjustment alone so I was almost like shooting a long pistol off of bags with a scope on it. No real shoulder rest.

[doctnj]

darn rain. Didnt get all the testing finished before the sky opened up and started pouring. What we did get was, I was right about the load for the 243. Its a freaking laser beam. I loaded 8 rounds and shot one hole inside a half inch diamond bullseye. Then turned around and rapid fired the remaining 4 rounds in the clip and they, although were outside the bull, they were all touching it. They were shot as fast as I could work the bolt and regain the target. So I feel real good about that load. Also 39.5 of IMR4350 is moving that bullet at 2977 with only 8 fps of deviation. Got to recheck the creedmoor zero and then the sky opened up.

[LongRange]

thats a great load right there now just shoot it!! im assuming you switched to the bergers?

[doctnj]

Yeah I did. I love the way they look and load. They load to the max length of the mag. The cbto is 2.249 using 2-24

[LongRange]

They shoot good in the wind too...very slippery.


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[doctnj]

Well today is in the books. I am moderately satisfied with it. We started out this day in front of the rain but wound up having to go back and shoot in the rain to get finished. Got to verify my load this morning but that was it. It did give me a chance to go home and make up drop cards with all the new data. The rain never stopped so we went out in it to get verification of the drop cards.

This is the only picture I took today. I didnt feel like it in the rain. This was one of the confirmation targets on the 243 of IMR4350 at 39.5gr pushing the berger 105 hyb. There are 8 shots on this target 4 through the center and 4 around the bull. The four in the middle are while shooting for a group. The 4 all around are rapid fire. As fast as I could go. Most of the other targets looked similar.
http://i1075.photobucket.com/albums/w435/doctnj/Mobile%20Uploads/20160807_181855.jpg
So we went out to see if the drop charts were good and T's rifle wasnt magically faster. Although she uses .5 gr less and is 30 ish fps faster. Our drop data showed us to be pretty even. It was a rush job to say the least and we only tested out to 300. But for what it was we got a glimpse at the fact that the scope was tracking and the sheets were on for a few yards any how.

Would you consider being a 10th high or low to be off enough to adjust your turret? And what would you think if you were a 10th high at 200 and a 10th of a mil low at 300?

[doctnj]

The last part of that was actually questions I was hoping for input on. Maybe no one noticed. Or maybe this thread is just past its prime. Just want to know If Im chasing ghosts with the high low issue that is so minor.

[LoneWolf]

Id you don't have your actual velocity your data may just be slightly off or the BC in your calculator may be off


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[LoneWolf]

I'm usually .3 mils to 200 and .9-1.0 mils at 300 with either the hybrid or the DTAC. I just make a note of what's best and move on.


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[upSLIDEdown]

If those 4 shots in the center are your zero, I'd say you're good... Lol.

Always make sure you have a solid zero. If you're a tenth off, that tenth will be linear throughout your data. If you're high at one distance and low at another, that's a velocity or BC issue most likely. Make **** sure you have a solid zero. Use a magnetospeed if you have access to one to get a solid velocity. Only Chrono I trust anymore. Use a Litz published BC. They're usually good to go. If you don't have access to a magnetospeed, use whatever you have, just know you may need to tweak it in the calculator.

Again. Solid zero. Good BC. I assume you have a good idea of velocity even if you don't have a magnetospeed. Use what you think is right. Shoot at a steel plate as far away as possible. Putting a waterline across the middle of the plate will make sure you have a solid aim and let you know your come up is getting you where you're supposed to be. Tweak your velocity in the app so the data matches your real world data. Then try closer targets to verify the data from your calculator is correct for them also.

[doctnj]

I used magneto speed on all three rifles. I know more testing is needed. This was a limited amount of data as far as shooting at any kind of distance but it brought up a good point. I have run into it before. I triple checked the distance to targets however that could still be the ONE issue I cant actually verify. Im using a vortex range finder. I have not had nor taken the time to check to see if it is accurate. Im just taking its word for it. I measure 4 or 5 times and require at least 4 readings to be the same to record that distance. Our velocities are average of around 10 shots and SD is typically single digits. Before now I would see it a little high at 200 and start in making adjustments. Then see its a little off further out and before you know it Im running the "truing" software and I wind up back with drops that seem to work but a reverse engineered MV and now a 100 yrd zero that doesnt fly. I think thats how we wound up in such a mess to begin with.

For the time being I am discounting those "off" shots to shooter error or daily condition and not adjusting anything and see how they behave over a couple days with different conditions. It is mostly likely going to be raining again this weekend. At the very least, I am getting an very good handle on working with my ballistics program. We are trying to get prepared to go up to MO to the 800 yrd range. I just want to feel like our data is good to go before making the trip. Also T and I are shooting our very first match next month. That is another reason Im being so darn anal about this out put. And then of course getting Em. out to 1000 yrds for the milk jug challenge. I dont want to be responsible for having jacked up data and cause her to miss because dad cant seem to get the drop tables right. lol

[doctnj]

FINALLY!!! All the data matches up with reality. All three rifles are shooting exactly where they should be or with in .1 mil which I have come to conclude is perfectly acceptable.

When we got set up, I realized that the grass in the field had just barely overgrown our line of sight to the steel target at 550. So I moved it up an unspecified number of yards. I tried to range find the target but could not get a reliable return on the RF. I milled the target and we corrected with spotting scope. So T wound up shooting her dope for 450. So to verify all three rifles against each other, I shot the other two at their respective 450 dope and all three hit. The 243 hit at the bottom edge of the 12" plate so that one was about .1 mil low. Although LongRange was right about windage with the 243 hybrid. Where the other two rifles required .1 or .2 mil windage, the 243 required none.

We are ready officially to head up to the 800 yrd range in MO to start our journey to competition. Going to commit the drop charts to lamination. lol

[doctnj]

I guess this is a very long lesson in not having anything take up the last bit of space between the scope and for end especially if its tight. The vortex defender scope caps are very pliable. I thought the mechanical force of the scope to the rifle would hold back the elasticity of the cap. Bad choice. The cap on my 260 is all but touching but it was not a tight fit although after a few coats of paint there is no more light coming through below it. The data supports that it has not been effected. One of the Vortex reps even remarked that his was in contact. Of course I had to lube and stretch the bad one.

Lesson learned.

[LongRange]

Glad to hear you got everything figured out.

I told you the 105g hybrids are the cats A$$ and they buck the wind....run them up to 3050fps(which is 100-150fps slower than most are shooting them)and they really shoot well!


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[doctnj]

They certainly are. I was thinking for sure they would be pushed even more than the 140's. Had to see it for myself. Because we shoot in a deep long valley, we have switching winds all the time. I finally put up some surveyors tape in a few spots to indicate wind down range. That helped a great deal. We normally make note of wind direction while down range setting up targets but that never holds for very long.

I made a modification to the Vortex scope cap so I could put it back on T's scope. Works pretty good and snaps closed without touching the rail hardly at all.
http://i1075.photobucket.com/albums/w435/doctnj/Mobile%20Uploads/20160814_113944.jpg