Load Tuning By Jerry Teo

[cva54]

Yes I am measuring off the ogive. The way I sean it it is the best way. But when I load a round to .020 jump the cannelure seams to be hangging out a lot. long throat? No I have'nt done the math to find out max for the seatting depth for the bullet Hornady .308 #3033 150 gr BT/SP interlock.

[Whitesheep]

I managed to make it to the range a few times since my last post. I am not done yet, but here is what I have found out so far. With 168 Berger VLD hunting bullets I am consistently shooting better groups 0.130 off the lands. I was surprised this was so far back, but it is within the range Berger suggested would be best. Now for powder development. I still haven't gone back to the Sierras, but I will when I am done with the Bergers.

By the way, I tried a load right at the lands. The T/C closed with no problem, but I generated over pressure signs with the first shot so I stopped. This is with a load well below the maximum powder charge recommended by Berger. Interesting.

More to come....

[kyhareraiser]

i've been reloading and shooting for some time now but i have picked up at least two ideas...one is the flagging tape to see wind direction .i can use this deer hunting since i hunt a flat bottomland..now the second i don't catch..i've always heard people fireforming brass but since i shoot new factory and then use those pieces of brass they are fireormed for my rifle..but now how ,do you use corn meal in front of the powder..how do you get it to stay in the casing..tell me,i have sme new brass and would like to do this

[rdsii64]

I must have to only two rifles in the world that shoot bug holes with decent factory ammo.
I simply duplicated the factory recipe and the rifle shoots better than I can. If I find that the next rifle to take up residence in my safe isn't so lucky, your methods seem like they will help me find what works quickly so I can spend less time at the loading bench and more time behind the rifle.

[rem]

that is very helpful thanks for sharing.

[Shootin4fun]

Originally Posted by Whitesheep

By the way, I tried a load right at the lands. The T/C closed with no problem, but I generated over pressure signs with the first shot so I stopped. This is with a load well below the maximum powder charge recommended by Berger. Interesting.

And there you have it...bolt closed OK but over pressure signs in a mid range load.

I've only tried seating to touch the lands a few times and did not have postive experiences. First, if the seating is off by just a thou or 2, closing the bolt is difficult if not impossible; scary and a pain in the a. (I rarely bring my press to the range to correct seating ;-) and won't test cycle all rounds through the gun at home before going out.) Second, the pressure difference between rounds touching the lands, and those that may be .001 off the lands is nonlinear. Variations in pressure between lengths that are not touching the lands are somewhat predictable, but touching vs. not touching seems very touchy!

Good conversation here. My method has been the one where a nominal lenght is chosen, a .4gr increment range of weights loaded (5 or 10 ea. weight), and then shot as groups at 100, 200, and if it is a good load then 300 yards.

My problem is fliers. Sometimes I have them and sometimes I don't, and I can't figure out whether its me or an external factor. I try to keep everything very consistent through reloading all the way to letting the barrel cool between shots of 2. I have loads that I know are capable of landing 3 out of 5 shots overlapping each other but then the other 2 often might be .5 and even .9" away. ES is around 40 and SD is around 20. But at 200 yards it consistenly holds 1" - 1.5" 5 shot groups, and at 300 yards anywhere from .8" - 3" groups. So it makes me want to change some reloading variable, but I don't know which one. Does anyone "true" their brass to make sure it is completely concentric? Its the last reloading variable I can think of.

Other than that, maybe I should let someone else who I know is a good shooter have a crack at some groups with my best loads!

[Shootin4fun]

So, after all the discussion, it doesn't seem like there is 1 best way do go about finding the most accurate charge / OAL combination to achieve the best accuracy. Some start with 1 length and vary the charge, then go back and fine tune the length. Some start with 1 charge and vary the length, then go back and fine tune the charge. Whitesheep started to do an experiment, but was thrown off track when touching the lands produced the best group ever.

Then there is the OAC method, firing 1 round each charge level and again at each length at different targets, etc. as has been explained in other articles, vs. firing all 3 - 5 of a given load at 1 target, then the next load, etc.

I don't know what to think anymore, so I'll just pray for a windless day when I have free time to go to the range.