New 6.5 ocw results

[DanNewberry]

doc, just try the 42.5 grains with a seating depth change, .005" shorter, and again at .005" longer. If it's on a true accuracy node, it'll tighten up and get rid of the linear group. That said, 42.7 may be closer to the actual OCW high node. And 41.4 to 41.5 on the low node is probably where you'll end up at.

[upSLIDEdown]

I guess my poi, poa idea is getting off track due to terminology. I just thought that if I zeroed my rifle with ammo that is "unknown" as far as excitation of barrel. There is NO WAY to definitively know if poi shift might not be your TRUE zero. Upslide keeps saying poi and poa is so important and should be the same. I could see that if your sighting ammunition had zero "excitation". What do we/I do after I think ive identified the correct load and it holds together...... re zero my scope to accommodate the slight difference in poi and poa. Now then the next test on the same barrel, the poi and poa should be the same because the speed of sound through that metal of your barrel is basically a constant; and upslides comment would be TRUE. Am I way off base?

I think we had a miscommunication. What I was trying to get across is what you've just said, I just may not have been saying it the best way.

When doing an OCW, nothing is going to actually hit you poa perfectly, and that's fine. That's the way it's intended. You want a rough zero, but changing the charge so much will almost certainly walk all around that point of aim. The key is finding a string of groups (usually 3 or so), where the center of the group is the same distance and direction from the point of aim. So say 3 groups in a row, the center of all of those groups is 1" from the poa, at 1 o'clock. Whatever the middle charge weight was should be your OCW. That way if you throw a hair over, or a hair under on your powder, you'll still be hitting the same point. The group size can then be tightened up by adjusting the seating depth. Once you've got the group tightened up, then you can adjust and zero your turrets so you're zeroed and should be good to go.

[doctnj]

Again, thanks Dan, as well as every one else that has chimed in. This truly has been a good crash course in load development. Which is a good thing because I was informed yesterday that the rail for one of my competition rifles will finally be here tomorrow!!!! I get to fire form brass this weekend then start load development on it next.

I wish I would have read Dan's post before I finished loading the entire test. Oh well. I did seat an additional .009 deeper than before. It puts me at a cbto length of 2.200. I like round numbers. Before seating more shallow I want to see how the pressure feels as the bolt seemed a bit sticky in the charge range of 42.7. I am re testing 42.5 and 42.7 again as well as 42.8. On the 42.8, I want to re asses weather the bolt gets noticeably more sticky at the new seating depth and that it spreads back out at that charge so I know indeed where my upper limit is. May be an incredible waste of time but hey its already loaded.

[yobuck]

Again, thanks Dan, as well as every one else that has chimed in. This truly has been a good crash course in load development. Which is a good thing because I was informed yesterday that the rail for one of my competition rifles will finally be here tomorrow!!!! I get to fire form brass this weekend then start load development on it next.

I wish I would have read Dan's post before I finished loading the entire test. Oh well. I did seat an additional .009 deeper than before. It puts me at a cbto length of 2.200. I like round numbers. Before seating more shallow I want to see how the pressure feels as the bolt seemed a bit sticky in the charge range of 42.7. I am re testing 42.5 and 42.7 again as well as 42.8. On the 42.8, I want to re asses weather the bolt gets noticeably more sticky at the new seating depth and that it spreads back out at that charge so I know indeed where my upper limit is. May be an incredible waste of time but hey its already loaded.

So why bother to fireform brass (first)? Unless its a major change in shape from the original, as might be the case with a wildcat cartridge?
Does not Dan's theory on initial load work up (OCW), rule out the need for perfect brass?
Are we wasting time, components and barrels by thinking otherwise? Mind you im not questioning you or the theory, but my interpitation of it is that it
looks for the optimal powder charge, not necessarily the perfect load. Which might be brought about by fine tuning of whatever it takes?
I have some confusion about high node low node and missing the node. Especially when looking at a good group.
Why would someone like me would consider the low node anyway? But i think i grasp the overall concept.

[upSLIDEdown]

I think you may have been trying to quote me, not Doc, but I'm not sure.

Fireformed brass will always be beneficial in my book, because it's always going to grow a little, and that's one less variable you would take out of the equation. How much difference it would really make though, I don't know. Some of that would depend on how tight the headspace was set on each particular rifle. I set my headspace pretty dang tight on a Go Gauge, to keep from having as much brass growth, and have even thought about setting it with new brass (for factory loadings, not wildcats obviously) to all but eliminate brass growth, but I've never actually done it.

As for the high and low nodes, the high node is often on the max pressure end of the spectrum, so going with the low node would sacrifice a little velocity, but would give you better brass life, and barrel life. My Creedmoor is running on a low node at 41.8gr of H4350 at 2690-2700 fps. There are a lot of people pushing them up to and over 2800fps. My load shoots one hole in my gun, if I do my part, and so far Ive gotten at least 7-8 firings on my brass and still have tight primer pockets, so I'm good with losing a little speed. It's all a give and take.

[doctnj]

Last firing, I used a Sinclair chamber gage and actually measured the head space. I discovered I hade .036 ish more than the trim to length. So I trimed them .010 longer. This could have been a contributing factor in the increase in pressure. So this time around I took them all back to standard length. I was changing too many variables at the same time to get definable results.

As far as fire forming goes, I've heard both sides. I am on here, the hide, 65 guys, 6.5 forum. On most of them I just read. When I see multiple EXPERIENCES that over lap I start lending some value to it. I fall on the side of having brass fire formed for most consistecy. I'm sure you can work up a load with out it but I think in my meager opinion that more consistency shot to shot, load to load would come from fire formed brass that gets minimally resized.
No?

[yobuck]

Whats trim legnth got to do with headspace? If we eliminated half the neck legnth, would it change the headspace?
NO it wouldnt. The definition of headspace is, (the distance measured from the face of the bolt, to the base of the cartridge, (case) when the round is fully chambered)
Depending on case design, adjustments are made from the shoulder of the case or the belt on the case. And its also possible to use both shoulder and belt on those cases having a belt, after the case has been fired in the gun.
But the neck has no bearing on it.
Case stretch is a different issue entirly. Case design can influence it to a degree, but it will always take place. Hence the need to occaisionally trim the case
Take 5 cases that youve pre fire formed and load them. Then take 5 new cases and load them. See if the groups vary much.
And after theyve been shot, are they not then fire formed?
If were looking for a (ballpark) figure on powder charge by shooting an OCW, why not fireform at the same time?
Brass stretch is controled by the chamber to a large degree. So even a low node will cause brass stretch in a factory or loose chamber. You could also have a die made for those tollerances
Im very well aware of the affect pressure has on brass as to its life expectancy. But i also spend $4.00 a dozen for live shrimp just so i can feed them to fish.
Do i really need the pressure, and do i really need the live shrimp? Thats not what im confused about with high node low node, and maybe why i need to stick with looking at groups

[doctnj]

You are correct, I meant chamber length. But the rest of the comment stands.

[LongRange]

buck the node part of the OCW gives the shooter options on the load/pressures he is comfortable shooting...ive found shooting an OCW test normally gives me 3 groups/nodes that will shoot well...1 group at low charge..1 group about mid range and 1 group at the high end or a little above...the idea is to shoot and tune the mid range load because it will be more tolerant of environmental changes and or a few kernels of powder variations or case capacity ect...

i...like you...prefer to shoot higher pressure loads to get the best performance i can from the bullets im shooting...in the OCW tests that ive shot in the last 4-6mos in 2 rifles i found 2 loads that shot very well at the highest end of the charge weights i shot and with a small seating adjustment both loads in both rifles group very well out to a 1000yds and are still very weather tolerant...i like the OCW method for load development because its quick and easy and i also think its best way for a new re-loader to start with.

ive shot a lot of ladder tests and they are effective as long as there isnt wind to deal with and the shooter is a good enough trigger man to shoot that distance....ive also shot a lot of 3 and 5 round groups at 200-300yds which is not a bad way to find a load but is better suited for mag type cals.

i guess it all boils down for the type of shooting your doing and how accurate the load needs to be...i shoot 600 and 1000yd F-class with the same loads i shoot at the long range varmint matches and do ok but this year im going to use one rifle for the F-class and see if i can tighten things up and shoot some higher scores this year.

[yobuck]

Thanks for the input, and i really do intend trying the OCW when i try some heavier bullets my 7mms.
As for the distance, we have our own range where i can shoot at paper targets at any distance i like up to 400 yds.
So id be doing the ocw at a longer distance to start with since id end up there anyway for my final testing.
As you know it's irrelevent how good or even bad my guns shoot at 100 yds.
But how im interpeting whats being said is, group size dosent matter. Its where the group center is in relationship
to the aiming point. And that good group here missed the node.
And by the way, that chick over there in the black bikini youve been watching for an hour, well she misses the node also.
Check out the fat one over there. Does that clear up how my feeble mind works? lol.

[LongRange]

LOL...yes it does....

just an FYI the OCWs i shot to find loads in the 2 260s im referring to...1 at .3g below the highest charge weight shot .2925 but at 500yds opened up a little more than i expected....005 deeper seating tightened it right up...and the other 260 shot mid .3s at .7g lower than the max charge i tested and a .010 deeper seating tightened that one right up as well out farther...so ill stick with the one in the black bikini!

[doctnj]

First off lets not bring bikinis into this. I barely no what to do with the powder. I just wanted to say that I am grateful there is a place like this where discussions of this nature can take place. I might eventually come to the same conclusion with out it, but in a much longer time frame. In many instances these forums can help with turbo learning by being able to be open to differing opinions. I really hope I can get out to run this last test this weekend but its not looking real great. Extremely cold and wet. I know you guys from the north would think nothing of it but Im an older southern boy.

[LongRange]

doc get you a shower curtain and get it done LOL!

[doctnj]

If I can get down the hill without killing myself, I'm going. I've got it in the truck this morning. I'm taking it in to have all the screws loctighted and torqued. I set the eye relief where I want it and they go over it and get it ready to go. And bore sight it. All that for about 20 bucks.

[doctnj]

Well today, at least for now, is out for shooting a test. It 30 degrees, not so bad by itself. Its sprinkling, not so bad by itself. But also the wind is 15 to 20. That might not effect a 100 yrd shot much, although I think 20mph would in my opinion. But deep down in the valley I shoot, if there is any wind at all it screams through there. So a 20 mile an hour wind seems to get focused and blows everything. Not to mention if you are already wet and cold. Besides I guess all I have is my panties to keep me warm lol. Im planing on tomorrow. Not quite as much wind and no rain however colder.

Trust me, I have a brand spanking new custom rifle that I can not wait to shoot but those conditions suck.

Look, im going to hijack my own thread for a moment and try to keep it short. With all the deer talk on hajefd's thread I wanted to get some opinions. I hunt on 100 acres, well 99, one acre has a house that was sold and the new owners have mutts they let run. During bow season I was at full draw on an 8 point and they ran it off right in front of me. I drew on the dog but let off. Ive been hunting this valley for 7 years and pay 7k a year to lease it. Im actually renting a cabin and get hunting rights. Ive tried to have conversation with new guy and he seems to refuse to put his dogs up. Ive asked him if he would just put them up on weekends. I have sat out there and listened to them circle the woods barking chasing off all the deer.

We did get three doe early on but we gave them to a family that needs the meat. So we finished the season with out meat.

What would you do about this?

[doctnj]

well I put on extra panties and went out to shoot the new 260. I have some pics of the targets and a video of some semi rapid fire that corresponds to some of the groups on the target. I had loaded up two loads; the first being a middle of the pack charge weight just to foul up the barrel, get zeroed and just basically to fire form the brass. The second load was just over max load. It will be later tonight or even tomorrow before I can get the pics and such posted. But lets just say that dude shoots. Ill go into detail later and talk about the conditions which was interesting.

[yobuck]

Well today, at least for now, is out for shooting a test. It 30 degrees, not so bad by itself. Its sprinkling, not so bad by itself. But also the wind is 15 to 20. That might not effect a 100 yrd shot much, although I think 20mph would in my opinion. But deep down in the valley I shoot, if there is any wind at all it screams through there. So a 20 mile an hour wind seems to get focused and blows everything. Not to mention if you are already wet and cold. Besides I guess all I have is my panties to keep me warm lol. Im planing on tomorrow. Not quite as much wind and no rain however colder.

Trust me, I have a brand spanking new custom rifle that I can not wait to shoot but those conditions suck.

Look, im going to hijack my own thread for a moment and try to keep it short. With all the deer talk on hajefd's thread I wanted to get some opinions. I hunt on 100 acres, well 99, one acre has a house that was sold and the new owners have mutts they let run. During bow season I was at full draw on an 8 point and they ran it off right in front of me. I drew on the dog but let off. Ive been hunting this valley for 7 years and pay 7k a year to lease it. Im actually renting a cabin and get hunting rights. Ive tried to have conversation with new guy and he seems to refuse to put his dogs up. Ive asked him if he would just put them up on weekends. I have sat out there and listened to them circle the woods barking chasing off all the deer.

We did get three doe early on but we gave them to a family that needs the meat. So we finished the season with out meat.

What would you do about this?

What are the laws regarding the free roaming of dogs in that area? Chances are he's breaking the law by letting them run.
You have a legal right to be using the property since you pay for a lease. Id be paying him one more polite visit informing him
of your intentions regarding the dogs should they run loose again while your hunting on your part of the 100 acres.
If their chasing deer, i believe you could shoot them regardless. The only other option would be to find another spot.

[doctnj]

It's in the country so there is no leash law. The land owner was going to sue or build a fence around his entire property. The law says that if I had farm animals and they were being attacked or any one in my family felt threatened then we have the right to shoot.

[yobuck]

Sounds like a case of the stuck-or and the stuck-ee. An you is da stuck-ee.

[sixonetonoffun]

I would let them know you hired a trapper to deal with coyotes and feral canines.

[doctnj]

I took the loads back out. They were split centered around the previously found high node and low node. Im just going to show the center target from each test areas because I feel that the dang rifle was a laser at these two loads. It was very accurate before and after these two loads as well so I feel pretty confident that ive found the right combinations.

On the first picture, there is a shot marked shank. I was supposed to have been shooting at an entirely different target on that shot. If you count in the center there are 5 shots clustered together. Also on the second picture, the pressure got to me and I pulled the last shot. After the first 4 shots nearly made one hole I kept saying to myself "dont mess up". Negative thinking wins out every time as you will see.

Im goint to chrony these two loads and see what the numbers say as well as run them out to distance to check if they stay good. I would have to also make a decision here as the lower powder charge although it will be slower, is it worth the barrel and brass life to use it and gain a little more bullet drop?

[doctnj]

The other question I have, and this holds true for all rifles Im currently testing. Would it be accurate to say that these are NOT both in an accuracy node because the POI is shifted in the second load? Meaning the barrel is pointing down more at exit. Or could the first one actually be where the barrel is pointing up a bit and the second one shows true center of barrel movement? Or if they are so darn accurate and repeatable at those two loads, and loads before and after that it really doesnt matter that much that I could just re set the zero on the scope, load up and press on. This is still an area that is a bit confusing to me. Because this test was centered around two accurate loads, there wasnt one target that was much if at all above .5 moa. I would finish shooting that string and say, 'oh well thats my load', then I would shoot the next string and best it etc.

[LongRange]

personally id tune the higher node but thats just me...the lower node is very nice as well and if your looking for long brass life,easy on your rifle and possibly a little more barrel life run the low node...the lower node will most likely be less sensitive to weather changes too.

[LongRange]

if your pulling last shots id say stick with one of those loads and get some trigger time...i think your loads are good but you need some work on mounting,holds and trigger pull.
i second guess my loads all the time but what it really comes down to is im not a good enough trigger man to consistently shoot 1 hole groups.

this was yesterday with the 260AI...4 rounds in the same hole and by not pulling or mounting or breathing or 10 other possibilities this group went from about a .290 group to about .413...



pick one of those loads and get some time behind your rifle and consecrate on the things your doing different every time you shoot....just like loading it has to be consistent EVERY TIME.

[yobuck]

Both good loads, why would you have to settle on either of them?
For paper punching why cant you use the lighter one, and for hunting
or longer target sessions the heavier one? Precise zero while nice, isnt
always a dial up and kill it anyway. A sighter shot is always a good idea.