How much should I reduce loads? New ADG Brass

[trout004]

Guys, I've heard that due to lower volume, one should reduce the charge by ~10% for new ADG brass. What are your findings?

I have been running 210 Bergers w/Hornady brass, 75.5 grains of VV N565, and GM215M primers, but I want to start with a new lot of ADG brass and try out the 208 ELD-M's. The old load with the 210's was running about 2975 fps out of the Seekins Havak PH2 - 26" factory barrel. Shot well at about 1/2 to 1/3 MOA at extended ranges.

For the new load, I am thinking of starting at 72.5 grains of N565 and then increase by .5 grain increments up to the 75.5 mark. Does this sound like a reasonable plan to check pressure? Any recommendations on how much should I back off at the low side? Thanks in advance for your advice!

 

[trout004]

Can anyone offer a bit of advice? Should I back off a few of grains to start? I'm not sure where I've heard this but 10% seems like a lot. Any help is appreciated.

 

[257 STW]

I would think 2 or 3 grns should be fine unless you are redlined with your current load. my .02

 

[trout004]

I would think 2 or 3 grns should be fine unless you are redlined with your current load. my .02

Thanks! I appreciate the feedback. I'll start at 3 grains and go from there!

 

[257 STW]

You should be fine, but as always watch closely for pressure signs and keep an eye on velocity as it can be a pressure indicator as well.

 

[trout004]

You should be fine, but as always watch closely for pressure signs and keep an eye on velocity as it can be a pressure indicator as well.

Yes, that's my plan. Will do. I'll report my results just for the heck of it. It'll be interesting to compare. I have have velocity data for every shot at the range out of this barrel so far. Just under 400 rounds...

 

[QuietTexan]

I have been running 210 Bergers ... try out the 208 ELD-M's.

New bullets, new work up.

Not just for pressure signs, but because you might miss the window entirely for where the new bullet shoots.

210 Berger to a 208 Hornady ELD-M is a big change, the three Berger options in 210 .308s are themselves pretty different.

 

[Levi8599]

When I switched from hornady to adg in my 6.5prc I think I started 2gr lower just because

 

[257 STW]

New bullets, new work up.

Not just for pressure signs, but because you might miss the window entirely for where the new bullet shoots.

210 Berger to a 208 Hornady ELD-M is a big change, the three Berger options in 210 .308s are themselves pretty different.

Agreed. I missed the part about the new bullet. The OP won`t just be able to go back to the same vel node as the 210 for sure. As you said... complete load workup.

 

[waveslayer]

Why not measure the case volume? Measure the old brass, measure your ADG brass and measure your once fired ADG brass.

Then use QL , make sure to true it and you'll know right off within .2 grains.

Problem solved

 

[ericbc7]

There was a recent post/thread that discussed how new brass can mask pressure signs in load development.
With that in mind, if you developed the load for accuracy (as opposed to peak velocity-pressure) in once or multiple-times fired brass, then it is unlikely you will see drastically higher pressure indications on the first fireing of the new, same brand, cases. High pressures due to different case volume is more important to consider when fired cases are of significantly different volumes as can happen when comparing cases from different manufactures. A 10% reduction in your load would be something like 7 grains which would certainly move the load outside of any node you may have identified. You may as well load the new brass with budget components and fireform them rather than waste your premium fixings.
good luck

 

[QuietTexan]

A 10% reduction in your load would be something like 7 grains which would certainly move the load outside of any node you may have identified.

It would be outside the node, but 10% can be re-shot in just a handful of loads if he was only changing brass. Sucks to essentially waste five to ten shots, but I think it's worth it to change to better brass.

You may as well load the new brass with budget components and fireform them rather than waste your premium fixings.

IMO in his case I agree, find a sub-max load that shoots, shoot it a couple of times until it falls apart, find the "forever" load. I use budget components for this, especially in a newer rifle. Mainly because what some people think are cheap components will shoot amazingly well, to the point I've used Barnes Match Burners for competitions because there's no need for an expensive bullet in some kinds of shooting.

Raise your hand if you tip Hornady bullets? Gotta learn on something, right?

That's the bench work answer, QL is the easy button for it if you want to work on the computer and shoot the least number of rounds. 223 Rem meh I'll shoot it. 300 RUM... I might be using math to save $50 in components.

 

[Mike D Texas]

Why not measure the case volume? Measure the old brass, measure your ADG brass and measure your once fired ADG brass.

Then use QL , make sure to true it and you'll know right off within .2 grains.

Problem solved

If you don't have QL and have new brass of both types, measuring case volume is the 2nd easiest way to get a ballpark idea.

 

[Recon$$]

Yes, that's my plan. Will do. I'll report my results just for the heck of it. It'll be interesting to compare. I have have velocity data for every shot at the range out of this barrel so far. Just under 400 rounds...

Please do, I shoot the same charge and brass with a 199 gr and will be making the switch in a few months.