A&d fx120i Help!!

[Mt.Boy]

I bought one last month. As a upgrade thinking it was gonna help my loads and groups out. Ever sense then I have got some of the worse extreme speeds and standard deviations I have ever had. Before I was dropping powder with a charge master lite and trickling up with a bald eagle scale and was getting great velocities and averages. Now they are all over the place. Any suggestions on what to try or is there something I am doing wrong thanks.

 

[Mikemci]

Drop your usual weight of powder with your RCBS lite, then put that on your new scale.
There will probably be a difference. This will be your "new" weight, to set the new scale to.

 

[LCazador]

Maybe you were just lucky before!? Have you done new load work with your FX120i or are you trying to use the same loads you used before. The load that weighed 32.2 grains before may be .2 over now on your new scale. Try starting over with loads and do plus and minus .2 and see if anything changes. My guess you're weights aren't the same as what you thought they were.

 

[RegionRat]

Unlikely to be from just the idea that you are on a different scale, but like the others have said you may have what we call a "gain bias shift" between the two instruments. You will want to eliminate this possibility up front because it would cause a direct shift in your charge weight. (A different question would be how big should a shift be before it takes your rig out of tune?)

That means you will need to try and check with a calibration weight. Use the ones that came with one scale or the other and see what the same 100 gram check weight says on both instruments.

If the two scales don't agree, calibrate the FX120 using your old cal weight and then see if both scales call something very close to your favorite charge weight the same.

If that exercise doesn't uncover a shift of more than 0.1 grains at your favorite charge weight, then you are going to have to look elsewhere for the cause.

 

[Mt.Boy]

Ok these aren’t the same loads I have been using. Should have mentioned that. I am working new loads up and it is all over. Some groups I might get 3 round that are consistent then one will jump up or down. Then sometimes they are all way different. I have loaded a charge and it be right on and before I put a bullet in it. Put it back on scale to check it. And it be off close to a whole gr. But not every time.

 

[RegionRat]

Ok these aren’t the same loads I have been using. Should have mentioned that. I am working new loads up and it is all over. Some groups I might get 3 round that are consistent then one will jump up or down. Then sometimes they are all way different. I have loaded a charge and it be right on and before I put a bullet in it. Put it back on scale to check it. And it be off close to a whole gr. But not every time.

Okay. Just to be up front, I am a horrible writer and often dyslexic, but I had to fight that my whole life. So I am not picking on you but will circle some to be clear.

When you say "I might get 3 rounds that are consistent and then one will jump up or down. Then sometimes they are all way different..." Do you mean the charge weight or the point of impact on the target? Later you mention weight directly, so I will assume you mean the weight of the charge isn't repeating?

You also mentioned "...and was getting great velocities and averages. Now they are all over the place. ..."

So, we could be talking getting the charge weight stats down, or we could be on a charge weight that gives noisy speeds regardless. First thing is to get the charge weight spread down to the level of the scale and then go test.

To get batch to batch consistency, you have to use the calibration check weights. Then it is important to keep checking that full scale gain value during the session to make sure you don't drift in zero or full scale gain.

Make sure you are not spilling any kernels or leaving any behind in the case if you are spot checking. They really should read within 0.02 grains of what you aimed at when you dropped charges.

First lets get your charges under control, then we will see if your loads behave on the target and chronograph.

 

[Mt.Boy]

Okay. Just to be up front, I am a horrible writer and often dyslexic, but I had to fight that my whole life. So I am not picking on you but will circle some to be clear.

When you say "I might get 3 rounds that are consistent and then one will jump up or down. Then sometimes they are all way different..." Do you mean the charge weight or the point of impact on the target? Later you mention weight directly, so I will assume you mean the weight of the charge isn't repeating?

You also mentioned "...and was getting great velocities and averages. Now they are all over the place. ..."

So, we could be talking getting the charge weight stats down, or we could be on a charge weight that gives noisy speeds regardless. First thing is to get the charge weight spread down to the level of the scale and then go test.

To get batch to batch consistency, you have to use the calibration check weights. Then it is important to keep checking that full scale gain value during the session to make sure you don't drift in zero or full scale gain.

Make sure you are not spilling any kernels or leaving any behind in the case if you are spot checking. They really should read within 0.02 grains of what you aimed at when you dropped charges.

First lets get your charges under control, then we will see if your loads behave on the target and chronograph.

Sorry I guess I should have explained better. When I was saying inconsistent I talking about velocities

 

[RegionRat]

Sorry I guess I should have explained better. When I was saying inconsistent I talking about velocities

Okay, so if you are happy with the charge weights, but suddenly the velocities are spread or noisy, the question is now... are we talking about the same tune as before but just a different scale?

 

[Mt.Boy]

I am using it for the first time working a load up for two new hunting guns. Haven’t tried it yet on my bench guns. But with my hunting loads I am getting the big variations in the velocity’s. I was just trying to find out if I was doing something wrong with it or maybe I don’t have it set right or something

 

[brokeasajoke]

Drop your usual weight of powder with your RCBS lite, then put that on your new scale.
There will probably be a difference. This will be your "new" weight, to set the new scale to.

Drop a few charges with your old scale and then weigh them on the 120 and see what they are. I ran into this when I used all my cousins reloding equipment and then transitioned to my own.

 

[RegionRat]

I am using it for the first time working a load up for two new hunting guns. Haven’t tried it yet on my bench guns. But with my hunting loads I am getting the big variations in the velocity’s. I was just trying to find out if I was doing something wrong with it or maybe I don’t have it set right or something

Hang in there. No instrument or tool is perfect, but that FX120i isn't worse than where you started.

Give yourself a chance to adjust to it.

Learn to check the full scale cal weight by starting out with checking it a lot.

You will then learn how long the instrument warms up and the things that upset it. If the temps in your loading room are very stable, then you will find you probably don't have much to worry about in terms of the scale calibration.

Making accurate charge weights isn't the cause of noisy velocity, but that also doesn't mean that you are sitting on the right charge or using the best recipe either.

Using an FX120 doesn't magically turn every recipe into a success but it will help you tighten up your charge weights. Let that scale help you get repeatable charges and put your mind at rest, then you can focus on the important part which is your search for a load recipe that tunes those new guns.

 

[CADDIE5]

Your neck tension consistency will affect your es/sd. Sorted brass? Scale levelled? Static charge eliminated? Rock solid bench? Are you seating bullets while scale is dumping charge onto pan? Air currents in reloading room affecting accuracy? My sd is single digit. Do you anneal? I put a bullet that weighs 75.12 grains on scale every 10 drops. FX12OI Scale never varies more than +.02 grains.

 

[INTJ]

I am using it for the first time working a load up for two new hunting guns. Haven’t tried it yet on my bench guns. But with my hunting loads I am getting the big variations in the velocity’s. I was just trying to find out if I was doing something wrong with it or maybe I don’t have it set right or something

This just means your new rifles don't like the loads you have tried. It's that simple. The A&D FX-120i has taken a variable out of your process--you now know the powders charges are consistent to a kernel or two.

Now a lot of guys here, and me too after reading your first post, thought you weren't able to DUPLICATE your existing Chargemaster loads. The answer to that has been mentioned, and that is to take you known good load and check it's weight on the A&D.

BTW, don't get to wrapped up in ES/SD. GROUPS on paper are what is important. Rarely does the best group have the best ES/SD, and a good tuning node will allow 20-30 FPS velocity variation.

ES/SD are just indicators, and unless they are over 25-30 FPS, if the groups are good and repeat, you are fine. Now if to see a 60 FPS SD, then the load needs more work.

 

[No.343]

Forgive me if I am derailing this thread. I just got an FX-120i last week also. Is seeing a consistent negative number shown when I remove the powder pan a good indicator of how the scale is performing? Of course, the negative number is the weight of the empty pan. My previous scale was not consistent, but the FX-120i has been very consistent.

 

[Mark W]

Forgive me if I am derailing this thread. I just got an FX-120i last week also. Is seeing a consistent negative number shown when I remove the powder pan a good indicator of how the scale is performing? Of course, the negative number is the weight of the empty pan. My previous scale was not consistent, but the FX-120i has been very consistent.

I also received a new FX 120i last week and mine is absolutely rock solid. The only time it moves is if I reach to pick up the pan too quickly it will move due to air current.

 

[RegionRat]

Forgive me if I am derailing this thread. I just got an FX-120i last week also. Is seeing a consistent negative number shown when I remove the powder pan a good indicator of how the scale is performing? Of course, the negative number is the weight of the empty pan. My previous scale was not consistent, but the FX-120i has been very consistent.

Yes. the tare weight of the cup you are using should repeat when you pull it off.

Learn to watch the zero. Once in a while, just due to luck the falling powder kernels might collide in a way that one gets enough energy to jump out and land on the pan.

By watching the zero and noticing the delay it takes to get back to zero, you will catch that issue.

 

[Mt.Boy]

Thanks for all the info

 

[divingin]

Drop a few charges with your old scale and then weigh them on the 120 and see what they are. I ran into this when I used all my cousins reloding equipment and then transitioned to my own.

As one more thing to check, weigh a single charge on the A&D scale a couple of dozen times. That will tell you if the scale itself is causing variance. If it comes up with the same number every time, it's not going to be the A&D causing your problem (well, not it's operational capability, anyway.)

Worst case, load up a few rounds of a charge that you know works in your rifle using your old equipment, and a few with the new scale. Compare how they shoot.

 

[SecondsCount]

You have made a lot of changes to your process, not just the scale. Powder charge weight isn't the only thing that affects velocity.

 

[CADDIE5]

Your negative number can be from a kernel that fell below the ss platen and you haven't removed it. Bump the straw while removing cup from scale.