Thread: Powder crackling when seating projectile

Just working up some new .300 Blk loads using 168 gr amax over 2205.

ADI website has max charge at 17.2 gr for a 168gr HDY hollow point. Note I don’t have the projectile from the data but it is the next closest one.
Trim length and COAL are as per the data.

At 17.0 gr when seating the projectile I can hear the powder granules crackling like they are going under a steam roller.
The change is sitting at about the case shoulder, below the neck. The boat tail of the projectile going about .17 / 4.5mm into the charge.

Is this sound something to worry about? Are the granules likely cracking into a different burn rate or more likely just finding their place in the case?.

Try using a drop tube to get your powder to settle better in the case and you may find the load doesn’t compress at all. I wouldn’t worry about it too much as long as it’s just a wee crunch and you’re not forcing the projectile down into the powder charge. Some of my most accurate loads have been compressed.

i probably wouldn't worry about it to much aslong as its only a little crunch, does the load data say what brass they are using? often different headstamps have different case capacity, but if your nervous you can always slightly reduce...

Yip; what the the guys have said. In effect you are compressing the powder but slight compression wont hurt.
Brass with thicker walls has less capacity eg, Lapua versus Hornady

If the data doesn't indicate that 17 grains should be compressed (normally there is a "C" next to the number) then you have at least one of two things going on...

1 thick brass that has less capacity and is causing the powder to fill up your cases higher than it would have in whatever brand cases the data provider used.

2 the bullet you switched to is longer and if you're seating down to the same coal then that means the base of the bullet is being pushed down into the powder more.

That's not to say that either of these things are an issue.

First - trickle the powder into the case slowly so they granules separate out - they pack down lower that way. If you just dump a load in, it will come up higher than if you trickle it in slowly. Very slowly if you are trying to get a lot in.
Second - there is nothing bad by definition about compressing a charge. Fill the goddam case to the top and then see if you can crunch a bullet down deep enough to chamber if you want.

The only thing is that if you have heavy compression, the powder will some times back the bullet out; it will spring back because it wont take that much compression. So the trick is to heavily compress it, dont be afraid of leaning on it and making it crunch, but afterwards you have to measure the OAL and check back after an hour and see if the cartridge length has grown, which means the bullet is being pushed out again. If its good after an hour then fine - but if you really leaned on it, and you know you compressed it a lot, then leave it over night and measure the OAL in the morning. If it's still the same length in the morning then you're fine.

The second other thing which depends on the cartridge because some cases are stronger than others, is that if you're trying to heavily compress a load, you might buckle the case at the shoulder area, which if that happens then obviously leaning on it too much and that wont work. Smaller cases usually like the .222 might do this too you. And for really thin cases, you might get a bulge in the case, like the 44-40, but this is less common.

(Another point might be if you are compressing a load with a cast bullet, which may be softer than a jacketed bullet, in which case you have to consider if you are deforming the bullet with the pressure of seating while compressing powder.)

Other than that, enjoy heavily compressing your powder. You cant hurt anything. It wont blow up while you do it, your're not doing anything wrong, and on average I think compessed loads are often more accurate.

Thanks everyone for your replies.
especially @JohnDuxbury, that was plenty of info and quite interesting.

I normally run my reloads near the lower end of the spectrum and look for accuracy before velocity so this was the first time in about seven years of reloading that I have loaded compressed loads.
It was mainly because there wasn’t much span between high and low that I decided to load closer to the high end.

I was just dumping the powder in as per usual but I normally give the cases a rattle and check for uniform charge heights as a last precaution before projectile seating. I will try the trickle method mentioned.

I will check COAL later today but at a guess, especially as the projectile is a BT I think it has pushed into the powder more than compressed it, it certainly didn’t have any feeling of resistance in the final part of the press stroke.

Just the sound. Which once heard, couldn’t be unheard. However this thread has been quite reassuring.

Trickle in slowly while tapping the base of the case helps the load pack down and helps avoid compression

I don't like the way they spring back to a longer COAL.
I used this once to figure out which loads were compressed.
I could overcome it by winding the micrometer seater (nice bit of kit) down another 5 or 10 thou and they would come out within mag length and CBTO for the lands but I didn't like it. Dont like the idea that the seating setting would need to be adjusted to compensate for differences in powder charge. Didn't trust it would be consistent.
I tried a short (3") drop tube but that didn't help. I guess more experienced old school reloaders could use this successfully.

If you are running the same COAL as a hollow point you are probably seating the bullet 2 or 3 mm deeper being a tipped amax.
Do you need to seat it that deep?

Like Chainsaw says ... slow and tap or as I have found, dump the powder in, then either rattle the case side to side in the reloading tray or hold the case tween thumb and fore finger... index finger blocking the mouth and give the base a few taps on a piece of hard timber... all to settle the powder down.

Tried them yesterday. No push out and no pressure signs. Also 3/4 moa groups.