650 powder issue

[MilkMyDuds]

10 months old XL650. I have not adjusted the powder screw for the past 6 months. Recently I happened to chrono my ammo for a major match and noticed the MV has gone up quite a bit. I pulled and measured 10 rounds and found the powder amount has gone up from 3.3 gr 6 months ago to 3.5 gr now.

Is this normal with XL650? Do you have to readjust the powder screw every few months? I have not done any adjustment to the press in the past 6 months. It appears that something loosened up in the past 6 months causing more powder to be dropped.

Any ideas what might be causing this?

Thanks.

[dauntedfuture]

I doubt that your powder measure moved. Its more likely that when you set it up and weighed the first few charges, you were getting a different measure of powder then when you settled down and had brass in all stations. As for velocity going up; I have to assume you are using the same lot of primers, bullets, brass, and powder. If you changed brands of anything that will effect velocity. Velocity from a given volume of powder will very based on the lot. Environmental factors and elevation will also change velocity as will the cleanliness of your barrel.

I highly suspect that your AVG velocity changed by 25 fps or so, and your ES is 50 fps, as such your "new" velocity could be well within the statistical window of your "old velocity" depending on how many rounds you fired.

In short, I don't think there was anything to cause as I don't think the powder measure screw moved... Did I forget to mention that volume of powder in the measure will also effect the weight of powder.. We also need the rest of the story, ie if your velocity went from 1000 to 1025 fps for the average of 10 shots, everything is the same...Oh yea, we also have to assume you are using the same chronograph.

[MilkMyDuds]

I did mess around with different powder amount at the very beginning. However, for the past 6 months, there is absolutely no change to made to the press.

I have been measuring 10-round powder weight from time to time. The most recent measurement I had on my notepad was done in early April and it was 33.1 gr/10 rounds. Earlier measurements are all around 33 gr/10 rounds.

I have been using the same WSP, N320, Bayou bullets and I even use same headstamps of the brass. I always keep the funnel 2/3 full, adding more powder every 200 rounds.

If it's just MV going up by 50fps I am not worried because the weather is turning hot, compared to previous months. However, the weight did go up by 6% all just by itself. This is what concerns me. Maybe this is normal?

[MilkMyDuds]

BTW the standard deviation of the MV for 10 rounds was 10.4 fps last time. Usually it is in the 8-12 range.

[Bkreutz]

My 650 powder measure will "creep". I verified this by putting a Sharpie mark on the body and the adjusting bolt. I've heard that getting the micrometer powder adjuster will stop that, but I haven't invested the time or money into that accessory, I just look at the black mark I put on it. I also check my charge weight at least once a month. I rarely have to change it after putting the black mark on the bolt and turning it back to the index line.

Edited May 25, 2016 by Bkreutz

[MilkMyDuds]

My 650 powder measure will "creep". I verified this by putting a Sharpie mark on the body and the adjusting bolt. I've heard that getting the micrometer powder adjuster will stop that, but I haven't invested the time or money into that accessory, I just look at the black mark I put on it. I also check my charge weight at least once a month. I rarely have to change it after putting the black mark on the bolt and turning it back to the index line.

I actually do this too. I have different color sharpie marks on the screw to match the ones on the frame:) The mark has not moved. I suspect something internal has loosened up, but I don't know what that may be. A complete tear-down may be in order.

[Sarge]

My 650 powder measure will "creep". I verified this by putting a Sharpie mark on the body and the adjusting bolt. I've heard that getting the micrometer powder adjuster will stop that, but I haven't invested the time or money into that accessory, I just look at the black mark I put on it. I also check my charge weight at least once a month. I rarely have to change it after putting the black mark on the bolt and turning it back to the index line.

Yep, mine would creep as well over time. I got the micrometer bar and it's pretty tight so it does not move at all unless I want it to.

Another oddity of the Dillon's is the tendency to throw a higher charge if you leave it rest for even a few minutes.

[RiggerJJ]

Just cranking out rounds without occasionally checking powder throw and oal? Hmmmm....

Edited May 25, 2016 by RiggerJJ

[Steve RA]

The longer you leave it with powder in it gravity will pack the powder slightly more densely and as it measures by volume - not weight - the charge weight will creep up slightly. Unless you run on the ragged edge of high pressure it won't make any practical difference. Also, if it creeps up a little your PF will also and that is a lot better than going the other way !

[Handloader109]

I've noticed that the weight can vary a bit when I leave some powder in the Hopper. But I always check the second drop (1st is dumped) to make sure that it is the same. Powder type can make a bit of difference too. I've a homemade micrometer on my 9mm feeder it doesn't move.