Which charge for this OCW?

taseal

Gunny Sergeant
Minuteman
Apr 18, 2011
1,492
14
40
SE FL
Ok, I went back to the range with less powerful ammo this time, and no pressure signs.

I can't tigten up my groups as much as I'd like them to, but that's just me needing more practice (I also do well with prone vs table, and used the table today) and a nice rear bag instead of my sock would make a big diff I think

To be honest, all these look roughly the same impact are to me... I can't really decide which is the optimum load. I will say that I'm trying not to concentrate on groups (not that any are great anyways) but 51.5 had pretty much 1 hole for 2 bullets...

Let me know what you guys think

Setup is -

Trued R700 LA .30-06
Rock Creek SS 5R 26" 1:10 M24 barrel
B&C A2 Stock w/Atlas Bipod and homemade rear bag from a sock
H4350 (50-53gr in .5 increments) with 208 amax. 3.459 OAL with Lapua Brass and FGMM primers

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Re: Which charge for this OCW?

What do you see when you look at your targets?

What do you notice AFTER the 50 & 50.5 groups?

Remember you looking for vertical dispertion.
 
Re: Which charge for this OCW?

I have found it's easier to find the OCW @ .2 grain increments. I have seen groups pull together and spread from a .2 and .4, in other words, I would have missed the OCW @ .5 grains. I figure out what my max load is and work backwards. I use QuickLoad to estimate what my velocities and pressures will be and I set a limit on the low end as to what is acceptable. Hope this helps.
 
Re: Which charge for this OCW?

<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: trevor300wsm</div><div class="ubbcode-body">

Remember you looking for vertical dispertion. </div></div>

Umm,no.......
 
Re: Which charge for this OCW?

<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: gvanhyning</div><div class="ubbcode-body">I have found it's easier to find the OCW @ .2 grain increments. I have seen groups pull together and spread from a .2 and .4, in other words, I would have missed the OCW @ .5 grains. I figure out what my max load is and work backwards. I use QuickLoad to estimate what my velocities and pressures will be and I set a limit on the low end as to what is acceptable. Hope this helps. </div></div>

This.....
 
Re: Which charge for this OCW?

You probably have a low node around 50 to 50.5ish, and a higher node between 52 and 53.

208's were a bitch for me too, with RL's 19 and 22, as they never really shot crappy. Coulda really been happy with about any load I fed the rifle. Ended up using much smaller increments of pressure change, and shooting them at 200 yards, just to make out the dispersions.
 
Re: Which charge for this OCW?

From what I see is a low node somewhere around 50.0-50.5grs, and I see a scatter node at 52.5gr, so ocw should be 1 1/2% above 52.5gr and will put the ocw around 53.3grs. Your 53gr load looks like its just coming into that node. I would try 52.8,53.3,and 53.8grs if your not seeing any pressure signs.This is my guess.

I'm going to be working on my 30-06 and 208's when my new barrel shows up. Plan on using RL-22, then maybe RL-17. If they dont work then old stand by H4831 or H4350. Keep us posted.
 
Re: Which charge for this OCW?

I'll try 52.8 and 53.3 but right around 52.5 I'm getting small primer craters, so at 53 it's getting more pronounced. at 53.8 I'm gonna start seeing ejector marks I think. I got the bullets and will take some pictures tomorrow

I think i'm limited to around 52.5-53gr with my setup.

still need to try H4381SC though, I'll pick that up as soon as I finish this 4350 (I hate letting powder go to waste lol)

I hear great things about RL-22 but being in florida, the winter can be low 30s and summer over 100... Doesn't sound too stable. lol

I had a couple fliers here (I think one was at 53.9) but here is few more loads. problem is, pretty much all these loads left extractor marks (this was last week) so I stopped at 53 today. (and disregard all the non target holes, it was just some backdrop paper that I used)

Aren't I looking for placement of the shots though, not groups? they all seem to be hitting the same exact spot.

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Re: Which charge for this OCW?

How far off the lands?did you change anything in your loads? Looking back at your target, even 51grs looks like scatter too, which would put your node around 51.5-51.7grs. Pretty hard to tell. One thing i learn is dont change anything. Ask Dan Newberry see what he thinks.
 
Re: Which charge for this OCW?

Correct, you're looking for 3 consecutive groups that have the same POI and not necessarily the tightest groups. That you can tighten with seating depth.

Trailrider is right about setting it back to lower the pressure.
Seating against the lands doesn't always give you the best accuracy. I know in my .204 that I have to set it back .160" to get my best groups. But then, there's a long leade in the chamber and I couldn't seat against the lands, anyway.
 
Re: Which charge for this OCW?

<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: Hedge</div><div class="ubbcode-body">Correct, you're looking for 3 consecutive groups that have the same POI and not necessarily the tightest groups. That you can tighten with seating depth.
</div></div>

ok, but they have around the same poi! lol....

to get any more accurate (with my abilities) i'm gonna need to mount the rifle down with like lead sled. This pretty much tells me to check for OBT results with QL and some chrono speeds with the highest reliable charge.

you guys are saying i'm touching the lands btw. I'm not touching the lands, i'm off .01 (3.549) (my chamber is 3.559)

I just registered on his forum, so i'm waiting to get it activated, we'll see what he says
 
Re: Which charge for this OCW?

On that last target, they're not really hitting the same point.
Connect the center each shot in a group to form a triangle. The center of the triangle will be your group center. You'll see how that center moves from group to group.

There's a free program called On Target that will help in plotting your groups. It'll give you a good picture of what's happening.

http://www.ontargetshooting.com/
 
Re: Which charge for this OCW?

Looking good. I knew there was some variation in POI albeit small. I'm thinking that your 51.5 gr load is your accuracy load.
It seems to start to open up at 52 gr.

Dan says there are 2 nodes to look for. 1 about mid range and another towards the high end. Don't know how the 53's are looking pressure wise. But this is one for the expert.
 
Re: Which charge for this OCW?

I posted it in dan's forums, he said it looks good on low 50s and to also try 53-53.3-53.6 so I'm gonna do that, but i'll use brass without marks so I don't get false readings, and we'll see how that does.

I won't be able to shoot for a couple weeks though, so i'll be back in few weeks to re-test
 
Re: Which charge for this OCW?

Kinda what I thought he'd say regarding the high end. He's good at what he does. With the way you're shooting, that little extra velocity at the high end may just give you the edge to give those .308 shooters a good run.
smile.gif
 
Re: Which charge for this OCW?

WHat do you think of those groups? I was hoping I'd be putting a bulelt on top of another lol... but now that I checked the moa with the target calculator, most of my shots of sub-moa at even sub half moa lol
 
Re: Which charge for this OCW?

Yup, sub MOA. It looks like you're a trigger man capable of what your system can do. Once you find your load you just have to tweak the seating depth and you should be making bug holes.

Looks like the 208 Amax has a secant ogive. If that's the case, it will be sensitive to seating depth. Keep your seating changes to less than .005" increments.
 
Re: Which charge for this OCW?

What ranges are you planning on shooting at? If you are going beyond 1000 yards often then go for the higher velocity, otherwise settle on the node around 50 grains and enjoy the longer brass and barrel life.
 
Re: Which charge for this OCW?

<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: Hedge</div><div class="ubbcode-body">Yup, sub MOA. It looks like you're a trigger man capable of what your system can do. Once you find your load you just have to tweak the seating depth and you should be making bug holes.

Looks like the 208 Amax has a secant ogive. If that's the case, it will be sensitive to seating depth. Keep your seating changes to less than .005" increments. </div></div>

thank you
smile.gif
I was hoping for one big hole, but I need to realize I'm still in the testing process I guess

<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: Linkless</div><div class="ubbcode-body">What ranges are you planning on shooting at? If you are going beyond 1000 yards often then go for the higher velocity, otherwise settle on the node around 50 grains and enjoy the longer brass and barrel life. </div></div>

honestly i'm limited to 100-300 within my immidiate area. (300 is every other month)

but there is a place about 4 hour drive away that alot of ppl go to which is a 1000 yard place. so i'm trying to set it up to be used there.

I honestly doubt i'll ever shoot the life of this barrel. once I dial everything in, it'll probably shoot few hundred rounds a year.
 
Re: Which charge for this OCW?

The lower node will be more than adequate for 1000 yards and while barrel life may not be an issue, I sure wouldn't want to have to replace brass more often than needed. If you insist on going for the upper limit maybe consider loading the lower node for the short range and the upper for the longer.