OCW load development need advice for a newbie

[Frogman77]

Hey guys, Newbie here...

I started some load development today trying the OCW method and could use some advice and maybe some expert input.
Here's the info: Howa 1500 .30-06 22" heavy barrel 208gr Amax RL 22 CCI 200. All bullets seated .005" off the lands.

Here's the first target with the velocities listed under each targetthey're hard to read sorry...)

So, then I also noticed that on my hogue overmolded stock (not the greatest I know but it's what was available) that the barrel wasn't free floating up front. So I took the dremel out and just took some of the rubber out and now the barrel is totally free floating, no contact. In hind sight I probably should have waited till I was done load developing....oh well, I learn the hard way.

So from here, I decided to break it down some more and do loads in .3 gr increments from 58.5 to 60.3.

however, shooting conditions weren't the greatest, the sun was directly in front of me and in my eyes and it was extremely hard to see in the scope. I'm sure I should have waited for another time when the visibility was better, but anyway here's the second target. Temp was also 10 degrees higher and baro pressure was the same.

so, I'm stumped. The groups were definitely tighter on the original target then things opened up a lot on the second target (I did run a bore snake between the two). Was it the lighting conditions? Was it me screwing things up by getting rid of the barrel contact??? 58.5gr the first target held a great group, the second target 58.5gr was not great at all.

58.8gr yeilded the most consistent velocites on the second target with single digit ES.

later today I'm going to experiment with seating depths using the 58.8gr charge and the 59.7gr charge from the second target. Starting on the lands working back in .01" increments to .03" off the lands.

Anyone have any thoughts??? Any advice would be great. THanks!

 

[mo]

Frog I think you did the right thing about free floating the barrel, but not during the middle of the load development. The first target you shot a couple of nice groups.
So just start over, clean your barrel good shoot a couple of fouler shots. I do think you need to to feel completely comfortable with your shooting ability when testing. If your not just wait till another day, when you are.
I also think you should back up to 200 yds if possible. Let us see your next targets when you shoot.

 

[BENNYBOOBOO]

Something I've tried with great success when running an OCW test is to actually measure out the group-centers of the various loads, poke a hole in the target, and then plot the individual points on a new target ( I call this the group-center-target). Rather than use identical points, mark each group center with the number 1, 2, 3, etc... This will usually give the shooter a much clearer idea of where the group centers actually plot in relation to each other, yielding a more easily identifiable OCW. If this doesn't give the information you're looking for, try moving back to 200 yards to open up group sized and give group centers a bit more space and variation.

Don't forget that when reading the Newberry OCW pages, it is important to initially disregard group size when trying to locate an OCW. This component can later be adjusted by varying seating-depth.

Hope this little bit of info helps.

Eben

 

[Michael Eichele]

The first thing I would do is try a different powder. If youre stick liked that powder, the groups definately would be smaller. You still have to find a sweet spot even with powders it likes, but even the "bad" groups will be better than most of the groups you have there. When you find the right powder, you will know.

It also isnt a good idea to move youre seating depths AND change charge weights together. One may cancel another out. Find one sweet spot at a time.

Just remember, youre just starting this proccess so dont get frustrated. It is just a matter of finding the right components. It will happen with time and persistence.

 

[fireroad]

Sorry to hijack this thread, butI've never heard of the OWC method until now. Is this a pretty popular load development method amobng the long range crowd? From what I've read it seems to favor consistency (closest to POI) over accuracy (tightest groups)?


Frogman77 - Plus one on not changing the seeting depth and powder at the same time. As for powders, if you are a Reloder fan RL-19 would be a much better choice with that bullet weight.

 

[Jay Kyle]

Sorry to hijack this thread, butI've never heard of the OWC method until now. Is this a pretty popular load development method amobng the long range crowd? From what I've read it seems to favor consistency (closest to POI) over accuracy (tightest groups)?

When building OCW loads, Step 1 is to find the consistant POI, then Step 2 is to find the tightest group by varing either the primer or bullet depth (individually).

Jay

 

[Frogman77]

thanks for the input guys, I'll try another powder sometime soon..I'm going to put a new trigger in too. the stock one isn't that great. Tons of creep in it and it needs to go. I'll keep you posted.

 

[Frogman77]

update. small update. At the advice of some of the experts I started fresh with some new brass and a clean barrel and this time starting at .02" off the lands instead of being .005" off the lands.

Nothing huge but I did a simple ladder test just to see where my max load would be and go from there.

RL 22, CCI200 208 Amax
T=60deg, Pressure 29.76, Light Rain. 100 yards

55.5gr - 2566fps
56.0gr - 2624fps
56.5gr - 2660fps
57.0gr - 2631fps (chrony error??)
57.5gr - 2668fps
58.0gr - 2661fps
58.5gr - 2705fps
59.0gr - 2743fps starting to see extractor marks but easy bolt lift
59.5gr - 2731fps
60.0gr - 2762fps extractor marks, still easy bolt lift.

picture of target:

Any input would be great. I think this combo has some potential. The group in the red outline are five shots with the charges listed in the according box.

Thanks again. I'm going to pick up some different powders to try too.

 

[BENNYBOOBOO]

Now it really looks like you ought to be working at 200-300 yards! All that variation in charge weights and you're still looking at a group that's barely over 1 minute! Seems to me that you've got a great shooter that was meant for reaching out and printing small groups.

Just out of curiosity- why rely on the chronograph to tell you where an accuracy node is? I don't get it. What does bullet speed have to do with where the different charge weights land on the target, especially so close like at 100 yards? Don't get me wrong, I understand that a large ES will open up a group like you wouldn't believe. However this would come in handy when an accuracy load has already been found by using the OCW test.

Seems to me that if we're worried about speed and horsepower of a cartridge effecting it's performance on targets and animals, we're probably shooting the wrong caliber to start with.

In the early stages of an OCW test, what does bullet speed tell us?

EH

 

[RockZ]

Looks like 57gr and 59gr both have potential as the shots around them are pretty close.
You can do an ocw with 56.5,57,57.5 and one with 58.5,59,59.5 and see what you get.
I'd try the higher one,59gr, first as it has the best velocity.

 

[Frogman77]

I needed to add to the post and I forgot to. but I started having some flattened primers at 58 grains. But the bolt was still easy to open. I've heard that flattened primers are unreliable as pressure signs..at about 59gr I started to see shiny marks on the back of the base of the case head from the extractor. Bolt still easy to open. IS it still safe to keep working those loads up?

I've spoken to some other folks working up these same loads and he's gone up as high as 61gr without pressure signs but, that's his rifle.

 

[jimbires]

I needed to add to the post and I forgot to. but I started having some flattened primers at 58 grains. But the bolt was still easy to open. I've heard that flattened primers are unreliable as pressure signs..at about 59gr I started to see shiny marks on the back of the base of the case head from the extractor. Bolt still easy to open. IS it still safe to keep working those loads up?

I've spoken to some other folks working up these same loads and he's gone up as high as 61gr without pressure signs but, that's his rifle.

if you are marking the brass case head that's when I stop , and back off a little . or switch powders , and start again . Jim

 

[RockZ]

Sorry, I didn't notice the ejector marks at 59gr.
Work around the 57gr load first and see what you get. You have plenty of velocity, lower pressure and a margin a safety.

 

[lever-hed]

I think there's some misconception that OCW is the key to making your rifle as accurate as possible. THere is nothing further from the truth. Only you can make your rifle shoot its potential. I agree there's lots of science behind it, and with ballistics software it helps a ton, but brush away the wool from your face and shoot and practice, there is a lot of art to it too! (just an alternate way of looking at things)..