Compressing powder during reloading. Good or bad? Opinions please

[Thomas Rutledge]

Opinions please. Thanks.

 

[John McLaughlin]

I've loaded many cartridges with compressed loads and have not had any issues. Most recent used was a 270 Roy shooting a 140 gr Failsafe on top of 79 gr of ReL 25, Fed gm 215 primers @ 3300 fps. It tipped over a B&C 179 1/8 Rocky Mtn Ram. Priceless. JM

 

[uplander01]

I try to minimize compression. There is something to be said for using all of a cases capacity, hence the kynoch wads in large cases to keep the powder column uniform, but when you are really packing it down IMO your going to see burn rate variance and velocity fluctuation. It will also be harder to set your seating die in one spot and get uniform seating. But if you must, a small trick I use, once all the cases have powder in them, use some sort of vibratory device on the corner of your reloading block and watch the powder granules setting down in the case, that is one way to minimize clumping or variance in powder load density.

 

[John McLaughlin]

I failed to mention the plaster vibratory trick. JM

 

[Nevada Mike]

I have used compressed loads - even mildly compressing ball type powders - in my 7mm RM. I found that 'full house' loads are usually more accurate and I don't have any pressure signs, tho' they have not been pressure tested. This is with 160 grain Nosler PT bullets. Taken several bull elk with zero escapees.

For stick type powders, swirl charging helps to settle larger loads in the same case.

 

[flatwater bill]

An interesting question that rarely arises in the literature. When I was a kid there was an old drawer with many old cartridges in it. Some were .303 British. They were old even then, and I'm older than most on this site; they were from about 1890 I think. Being a well behaved kid, when no one was looking I cut some of them open. They were loaded with black powder. The amount was 70 grains. (Only about 35 grains fits in this case. ) It was compressed as hard as a piece of wood. A single woody block. And it still worked. I always wondered then why it didn't detonate on compression (I now know), and why it still worked, but I've always thought of this when reloading. I cut apart many old Kynoch loads with cordite sticks and a Jute wad filler also (some in collectable African calibers before I was reigned in). Their old powders had the burn rate of about IMR 3031 and were too fast for a full case, hence the Jute wad to hold their feet to the fire. I never load half grain charges, and never compress smokeless (those grains crunching is like fingernails on the chalk board), always compress black. But the are JMO, and all the manuals have compressed loads listed, so they must be fine. Thanks for posing a good question...........good luck with your reloads.........FWB

 

[Vintageguy]

Ok, a different opinion. I know the consensus of 100 percent case fill and accuracy. But in my personal experience that hasn’t been the case at all. Might be my guns preferences but my best loads are not compressed and I like hearing the powder when I shake one and not the crunch when seating a bullet on a full case.
Completely different when it comes to black powder. I use a drop tube and compress the piss out of it for the best loads.

 

[JimP]

If you look a number of the manuals out there denote that their better loads are compressed when you reach the maximum loads.

My .340 Weatherby's most accurate load for the 225 grain TTSX is a compressed load and the manual states it.

Now when it comes to black powder you want a compressed load. A air gap will just lead to trouble. When I was loading my 44-40 and 45 Lc with black powder I used a 2' long drop tube to dump the powder along with compressing the loads by about 25%

 

[crs]

I compress powder when needed to reach an objective, otherwise it is not an issue.
Some powders compress better than others. For instance, a 24 inch drop tube will be all that is needed for many ball powders. Enough said.

 

[PHOENIX PHIL]

I've done it but usually not in a big way, but my 458B&M is an exception. We can't seem to put too much powder in those cases for the powders that are used. As such my loads are quite compressed. So much so, that if on bullet seating I immediately raise the bar after hitting bottom, the bullet will "spring" back up a bit.

So in addition to using a drop tube, I'd recommend measuring your bullet lengths closely and paying attention to the feel of the bullet being seated. It was that feeling of the round pushing back on the ram that made me check that.

Solution is simple, after lowering the bar to the bottom, hold it there for a few seconds and then leave it. Move on to measuring out your next load of powder and fill your next case. By now the compression of the powder has settled and the bullet will not spring back. So I remove that now loaded round and seat the next bullet.

 

[sestoppelman]

Often compress loads, never an issue. I remember in my .280 Remington, load the case with about 61+ grs of H4831, big chunky powder, tap the case on the bench to settle a bit and crunch those 160 Noslers into the case. Very accurate and fast!

 

[meigsbucks]

No issue with compressed loads. Several rifles do their best work with such loads. Where I draw the line is if there is so much powder, it has an effect on seating depth, at which point I’ll back off a grain or two.

 

[sestoppelman]

No issue with compressed loads. Several rifles do their best work with such loads. Where I draw the line is if there is so much powder, it has an effect on seating depth, at which point I’ll back off a grain or two.

When that happens I just get a big hammer and bang on the press handle, until that danged bullet stays put!

 

[Wyatt Smith]

I try to minimize it, but am certainly not afraid to compress loads.

 

[baxterb]

Just a slight crunch at the very end of the stroke for some of my loads. For whetever reason I prefer to be as close as possible to compressed. My BIg Game loads in my 9.3 are about as lightly compressed as you can get. I have been told alternately to and not to compress ball powder. I checked with Ramshot and they say it's OK. I;m glad, because it's a hell of a load - and no pressure signs.

 

[lwaters]

I always loaded my 270 with 62 grains of H 4831in a Winchester case. Had to tap the case to get it in. It wouldn't fit in a Remington case. That was with 130 gr. Bullets.

 

[CoElkHunter]

I always loaded my 270 with 62 grains of H 4831in a Winchester case. Had to tap the case to get it in. It wouldn't fit in a Remington case. That was with 130 gr. Bullets.

I locked the bolt once upon firing when hunting pigs with 63 grains of H4831 under a 130gr Sierra BT in my .270 Winchester M70. Guess it was a tad too much powder, but still got the pig. I know I shot that same load at the range before the hunt, so I don’t know what happened. Was using Winchester cases too.

 

[Shootist43]

There is compressed and than again, there is COMPRESSED. I don't mind going to 106% or so but I'm hesitant to go much over that. I too tap the case to settle the powder prior to seating the bullet.

 

[Aussie_Hunter]

The load I use in my 458 Lott is slightly compressed, no issues, no pressure signs etc And I have also experienced better accuracy with slightly compressed loads.

 

[Shootist43]

Aussie Hunter, that has been my experience as well. In addition, based on my experience loads that are closer to the maximum are more accurate than minimum loads.