Adjust powder or coal?

Thanks a lot for the help guys. Yes, no excuse for the three shot group's. From here on out, it will be at least five. As far as my distance from the lands, I used the Hornady over all length gauge and checked three times. My reading was 2.830 from base to tip or, 2.256 measuring base to ogive. I am seating at 2.800 so if I'm understanding everything correctly I am giving myself a .030 jump. But these readings are with the Hornady modified case. I guess once I start working closer I should Compare the modified case with one of my fire formed trimmed resized case. I would compare this using my T7 press with a Redding instant indicator, then plus or minus the difference from the 2.256 ogive reading. I guess that should give me a more accurate reading.if this is correct and you think necessary. Thank you again for all the help I don't have shooting buddies so all my knowledge has to come from the firing line and trusted YouTube channels.
 
ka9fax
I have that Hornady OAL gauge, will get you in the ball park but that's about it. Your fire formed cases, are they neck sized or full sized.? I found the using a Go gauge for my 308 very helpful in getting me my exact chamber headspace. The Go Gauge measures 1.630 when installed in your chamber your bolt will close.l cut pieces off a feeler gage to shim on the back of the gauge, it wouldn' close with a .002 shim, did close on .0015. Now I know my chamber is 1.6315. With an unprimed sized case l make a sample bullet seated to jam & back it down till it just touches the lands. That's my starting point measurement to jump or jam. Wish I used the Go gauge a long time ago , would have saved me money on trying every gauge I read about.
 
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Metal god said:
That said looking at your groups and applying the OCW method/theory of groping compared with POA to POI . I see two different possible nodes . 39.5 and 40gr are pretty much in the exact same spot on the target so that could be a nice light easy on brass plinking load . 41 through 42 seem pretty close as well as the same POI if you were to triangulate the groups .
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I don't like OCW at 100 yards, I was never able to get the results or read the results like I wanted. I found OCW worked much better as a ladder test at 300 yards or greater. I ditched OCW in favor of finding pressure and then adjusting seating depth.

The reason I ditched OCW wasn't because I didn't think it wasn't working. I ditched it because I liked it better for longer range load development and trying to read the nodes was a PITA on the ranges. Trying to get the range to go cold so I could go down and read the results at 300 yards was an exercise in futility.

I found running a seating depth test once I found pressure worked well at 100 yards. I didn't have to wait on the range to go cold to read my results, as I had four separate targets to look at in my spotting scope. I also found that once I found the proper seating depth for the bullet it worked very well at longer ranges as well.
 
taylorce1,

I don't really disagree with anything you just said . I only used the OCW method of reading the groups because there were to many rather good ones . I figured the next best way to eliminate groups was to look at POI to POA .
 
This might be a silly question, but I keep thinking about this, so I'm going to ask. In the area where I live I have to drive over a hour to get to the 100 yard range. The maximum there is 200, but I have always just shot at the 100y. I decided to redo my ladder test over with five shot groups like metal God suggested. But I wonder if this time I preform the test at 200 yards that way I would be able to see the spread better. My question is, once I find the tightest group at 200 would that still be the tightest group as you move down in yardage? Or does the OCW do funny things and I would have to repeat the test at whatever yardage I would be shooting at. For instance, A person preforming his ladder test at 500 yards once he figures things out should The group be extremely tight at 100? or are things not that necessarily simple. My goal is to find the tightest group at 100 yards.
 
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ka9fax
Once you reached the charge weight & bullet that is your tightest group at 100 yards , say 1/2" group . Will probably group 3/4" & 1.5 to 2.0 low, shot from a level position with any cant right or left. Longer distances I would zero longer, develope a load with a heavier bullet if twist will allow, to buck the wind. Going the other way that heavier bullet & charge may not group so well at 100 yards
 
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Thank you cw308. I fig, there would be more to it...lol. The twist is 1-12. i was told by the barrel maker that it was made after the M40A1 and 168 -175 should work well.
 
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I decided to redo my ladder test over with five shot groups like metal God suggested.
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What do you mean by ladder test ? I did not realize that's what I was looking at in those targets . Are you talking the traditional ladder test where you're trying to find a stable zone with in the charges that have a consistent POI area in relation to POA or are you talking a ladder test that just moves up the charge weight ladder from minimum to maximum charge ?

They are two different test that are read differently and are generally shot at different distances . The former needs to be shot at a minimum of 300yds and only uses 1 or 2 shots at each charge and you should use a quality front rest and rear bag . The later is more of a traditional load development that can be done at any distance but is generally done at 100yds .
 
What's the recommended bullet weight for 1:10 twist? For 100yrds, 300yrds, 600 yrds and 1k? Didn't know if there was any info for that. I shot 1k with 168 amax and 43 grns 4064, my grouping was about 14". I plan on improving that.
 
A 14" group at 1k is pretty darn good , with 168's ta-boot . You must be at altitude , 5000 feet+ ???

I'd think heavier is what you need to buck that wind a bit better . !90gr SMK would buck the wind much better then the 168's . How heavy can you go with a 1-10 . As heavy as you want to go . Hornady's 208gr ELD-match would do well

210gr SMK requires a 1-10 twist
https://www.sierrabullets.com/store/product.cfm/sn/9240/308-dia-210-gr-HPBT-MatchKing

Either bullet could use IMR 4064 or Varget and the like but I'd try a slightly slower powder for that heavy a bullet in 308 for 1k . Something like N540 or even IMR 4350 . What ever powder you use you'll need to reach 2400fps for best results but those may do well a little slower do to there high BC .
 
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Metal god,
oh, no i did not realize that. I just looked up ladder test, and see the difference. All i did was shot for dead center every time at 100 yards.:o
 
I should mention I only did that once and it was in LA. I flew down there for a weekend sniper course. It's called International Tactical. So in all honesty I don't think I could pull that off each time. Funny thing I have two boxes of 208 grn eld match. I ordered them a few months back. After reading alot of forums this size was reccommend for 300 win. So after reading your post and what sierra has listed (even though they are not the same bullet) I think I will try it. I looked on hornady website and couldn't find load data for that size bullet in 308. I will keep searching
 
Although not the exact same the Hodgdon's website has the 208gr A-Max data .

IMR 4064 Min-37.7gr Max-41.0C / COAL 2.820

Varget Min-38.1gr Max 41.5C / COAL 2.820

CFE 223 Min-40.6gr Max-43.7gr / COAL 2.820


Hornady manual has the 208gr A-Max and BTHP

With Varget maxing out at 40gr and 4064 at 41gr / COAL 2.800

Although the manual and website seem to have them seated pretty short IMHO . If I were loading them they would likely have a much longer COAL when I loaded them .
 
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Metal gold
Thanks. I will use your data and compare with what I find. Should give me something good to start with for the 208 grn. It will be several months before I have the opportunity to shoot out to 1k. Till then it's only 300yrds.

So earlier tonight I was collecting coal data with my hornady oal gauge and bullet comparator when I realized something. The calipers would not line up perfectly with the head and tip of bullet. Because the comparator is offset once tightened down to caliper. Not sure if this happened with past readings but regardless it is directional. I may be the last one to know this but thought I would share it. In my case I had to put the tightener screw facing backwards. After that it worked perfect.
 
Well just got back from a paid weekend at the firing range courtesy of the Army Reserves, and just checking in. towman32 please post the results what ever you find out and let us know what worked for you.
 
Quick update, I've loaded 30 rounds to try out. Using imr 4064 with 168 amax (starting with these then working into the eldx and eldmatch.) I've set the bullet .005 off the lands. Using new unfired hornady match cases. Winchester primers and trimmed cases down to 2.005
5 @ 40.5 grn
5 @ 41 grn
5 @ 41.5 grn
5 @ 42
5 @ 42.5
5 @ 43
I'm stopping at 43 even though the book says max load is 44.9. Since I'm starting my load testing jammed I will assume I won't need to go higher. My past experience has left me with primers blowing out even at 43 grns.
My plan is to pick the best grouping and play with +/- .1 grns. I will give an update as soon as I have time to shoot. Unfortunately could be a few weeks.
 
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