ADG - reduce load

[goathunter]

TLDR:
Does anyone have experience switching from a load with say WIN brass to ADG? ADG states to start with a 10% reduction, do you feel you need to?

Long version:
I started a thread on this about a year ago but didn't explain very well. I have shot a 300wsm forever and had a good load book max 180NAB 64gr RL17 and WIN brass. Then I sold it, but a new 300wsm (Tikka), chopped the barrel to 20", got a suppressor, bought ADG brass. So I switched everything. I really wish I could've switched to ADG in my old gun because I had such a good baseline with it.

10% reduction would be a 6.4gr reduction! Instead I did ladder style work ups with a chrono until I found what I thought would be max - using Gordon's reloading tool software. then shooting groups would start to see pressure - ejector marks and heavy bolt lift. Reduce load, shoot groups, eventually see pressure. And I've been iterating on this a few times. My last round I was at 62 grs 2794fps, say 4th shot see ejector mark. Today I am at 61.5gr 2774FPS and see an ejector mark on my 5th shot. I think I'm almost there, but what would you do? Drop more substantially?

 

[DEW0341]

Are you referring to the 10% reduction on first load only on virgin brass?

If so I did this on all my new ADG 7mm PRC brass using an old jug of IMR4831 laying around. I’m only on 3rd firing doing normal ladders and shooting, can’t seem to tell if it’s made any difference so far regarding overall brass life at this point.

What I can say is that my shoulders have not grown at all. I’m hitting pressure with every powder and bullet combo anywhere from -.5 to +.5 of book max.


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[goathunter]

Are you referring to the 10% reduction on first load only on virgin brass?

If so I did this on all my new ADG 7mm PRC brass using an old jug of IMR4831 laying around. I’m only on 3rd firing doing normal ladders and shooting, can’t seem to tell if it’s made any difference so far regarding overall brass life at this point.

What I can say is that my shoulders have not grown at all. I’m hitting pressure with every powder and bullet combo anywhere from -.5 to +.5 of book max.


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Now I can't find where I read 10% on their site, but I do see they say -

We recommend using a reputable load data source and working up from their recommended minimum starting loads. Failure to reduce charge weights established using other manufacturers brass may result in higher pressures and velocities while using ADG brass and may result in unsafe pressure levels.

 

[35WhelenAI]

It's reloading gospel and practice (otherwise, it's laziness or ignorance) to reduce (10% is a smart guide) when switching to ANY new component. Any reputable reloading book, reloading guide or source will give similar advice. If the extra time, powder, primers, brass and bullets to reduce loads and verify when switching to a new component(s) is driving your post (why the question if it isn't), don't reload.

 

[goathunter]

It's reloading gospel and practice (otherwise, it's laziness or ignorance) to reduce (10% is a smart guide) when switching to ANY new component. Any reputable reloading book, reloading guide or source will give similar advice. If the extra time, powder, primers, brass and bullets to reduce loads and verify when switching to a new component(s) is driving your post (why the question if it isn't), don't reload.

My question, the first sentence in my post, is asking if anyone swapped WIN brass load to ADG, and how that experience was for them. Do have this experience? If so, please share.

The rest is just an attempt to explain my experience in doing so. Which, if you read, includes a powder reduction with a ladder workup. I'll keep reloading thanks for the tip, been doing it for a couple decades.

 

[wind gypsy]

The screenshot below is standard "reduce by 10% language" used widely by ADG. ADG brass isn't smaller on internal volume by 10% than all the others, its just boilerplate language used liberally. If you want to know how much different the case capacity (volume) is than other brands, measure it by filling the cases with water and weighing them to get H20 capacity. In some cases ADG capacity is not smaller at all. Unless i knew a particular ADG case was way low on capacity comparatively i wouldn't waste my time reducing a charge that much.

Capacity is but one part of the picture, there are other aspects that contribute to pressure signs. On ADG particularly, tightness at the base of the brass in chambers is one item that contributes to pressure signs. In regards to the original post, i wouldn't worry about an ejector mark if there are no other obvious pressure signs with that bullet at that velocity.

 

[goathunter]

The screenshot below is standard "reduce by 10% language" used widely by ADG. ADG brass isn't smaller on internal volume by 10% than all the others, its just boilerplate language used liberally. If you want to know how much different the case capacity (volume) is than other brands, measure it by filling the cases with water and weighing them to get H20 capacity. In some cases ADG capacity is not smaller at all. Unless i knew a particular ADG case was way low on capacity comparatively i wouldn't waste my time reducing a charge that much.

Capacity is but one part of the picture, there are other aspects that contribute to pressure signs. On ADG particularly, tightness at the base of the brass in chambers is one item that contributes to pressure signs. In regards to the original post, i wouldn't worry about an ejector mark if there are no other obvious pressure signs with that bullet at that velocity.
View attachment 762844

That's where I read it, thanks. I did measure water capacity don't have that info on me but I think it was as you say, not crazy different. I think I have some goofy things going on with this gun.

 

[wind gypsy]

I wouldn’t worry about faint ejector marks much unless you’ve got sticky bolt lift and flat primers too or they are really stamped in there hard.

 

[35WhelenAI]

My point was, it is standard reloading practice to reduce loads when changing any component, it doesn't matter what brass is being switched from or switched to, or who puts that in their literature. ADG is printing that to cover their bases. With your experience of reloading for decades, I apologize that I didn't read into your post that you already knew that. As has been said, ADG is doing what every other component manufacturers does.

 

[Fireflyfishing]

I wouldn’t over complicate this. You’re looking for the quick and easy button. New rifle, new brass, work up a new load. Pretty simple.

 

[Mattman215]

I had to reduce my charge when going adg to Peterson guess due to brass thickness. I have not gone the other way.

 

[thinhorn_AK]

I backed off .5 grain with my 308 load because I was getting some flow going on.

I just loaded 46g varget with my accubonds, used that load a bunch. I was getting 2770fps, I backed it to 45.5 and not getting the flow. Still getting walkover 2700fps.

Who the hell has the time or money to back of 10% and work back up?

 

[goathunter]

I wouldn’t over complicate this. You’re looking for the quick and easy button. New rifle, new brass, work up a new load. Pretty simple.

I did work up a load. Then shooting groups of worked up load would eventually start to see pressure. Then reduce, see pressure, then reduce. New one for me. And I am not .5 grain low I'm 4 gr below my old load. Too many new variables at once, I think along with less capacity brass, I have less capacity chamber. But it is a saami chamber so could it be something else? Carbon ring maybe? Suppressor back pressure or something?

 

[goathunter]

My point was, it is standard reloading practice to reduce loads when changing any component, it doesn't matter what brass is being switched from or switched to, or who puts that in their literature. ADG is printing that to cover their bases. With your experience of reloading for decades, I apologize that I didn't read into your post that you already knew that. As has been said, ADG is doing what every other component manufacturers does.

All good I understand I was just trying to let you know I'm not a total rube, just a little bit of one. Years of reloading experience doesn't really mean much anyways, I'll never claim to be an expert. Yes all mfrs do say this, I've just seemed to be an edge case where it's true and was reaching out to see if anyone else has this experience, which sounds like the answer is no or they end up reducing just a little.

 

[35WhelenAI]

Who the hell has the time or money to back of 10% and work back up?

Really?

 

[Fireflyfishing]

I did work up a load. Then shooting groups of worked up load would eventually start to see pressure. Then reduce, see pressure, then reduce. New one for me. And I am not .5 grain low I'm 4 gr below my old load. Too many new variables at once, I think along with less capacity brass, I have less capacity chamber. But it is a saami chamber so could it be something else? Carbon ring maybe? Suppressor back pressure or something?

What was the velocity of your old loads?

What velocity are you hoping to get?

 

[thinhorn_AK]

Yeah man. Powder is up to ~ 60 dollars a pound when I can actually find it. Why change up the load when you have something that works?

Not much experimenting going on, I’m just using book loads. I’m not going to dick around with tenths of a grain unless I have to.

I load the max from the book, shoot it, if I get pressure I back off half a grain until the pressure signs stop.

That’s what I did with my ADG 308 load, 46g varget had some slight flow so I backed off half a grain and the pressure signs went away.

If I backed off 10%, that would take 4.6 grains off the load, then what? Keep loading them 5-10 at a time going up slightly and just burning through components to get back up to 45.5 where I ended up?

I’m sure ADG says 10% to cover their asses but that seems like a waste of time and components.

 

[wind gypsy]

Yeah man. Powder is up to ~ 60 dollars a pound when I can actually find it. Why change up the load when you have something that works?

Not much experimenting going on, I’m just using book loads. I’m not going to dick around with tenths of a grain unless I have to.

I load the max from the book, shoot it, if I get pressure I back off half a grain until the pressure signs stop.

That’s what I did with my ADG 308 load, 46g varget had some slight flow so I backed off half a grain and the pressure signs went away.

If I backed off 10%, that would take 4.6 grains off the load, then what? Keep loading them 5-10 at a time going up slightly and just burning through components to get back up to 45.5 where I ended up?

I’m sure ADG says 10% to cover their asses but that seems like a waste of time and components.

Quick single shot per charge weight ladder with a chrono. Find the charge that gets you roughly the same velocity as before or similar margin below pressure signs and run with it.

 

[35WhelenAI]

Quick single shot per charge weight ladder with a chrono. Find the charge that gets you roughly the same velocity as before or similar margin below pressure signs and run with it.

Agree. For the most part (exceptions exist, and exceptions are not common with respect to this), velocity = prsssure. Drop 10%, check velocity with a couple shots. Go from there. 1) the 10% reduction has been followed and 2) velocity tells the overall picture along combined with pressure signs already being monitored.