Compressing powder for .223 loads

[Sky Dog]

I have always been told never compress powder in reloading. The logic is obvious. Why is it I've seen .223 loads for Varget (I think) coded with a
(C) to signify compressed. Is this unique to Varget? .223? Some new revelation in reloading. Currently I use 69 gr. SMK's w/ 25 gr of varget. My
Bushmaster Predator (1:8 twist barrel) loves it.

 

[HexHead]

Isn't indicating a max load? I'd back off from that.

 

[Reloadron]

I have always been told never compress powder in reloading. The logic is obvious. Why is it I've seen .223 loads for Varget (I think) coded with a
(C) to signify compressed. Is this unique to Varget? .223? Some new revelation in reloading. Currently I use 69 gr. SMK's w/ 25 gr of varget. My
Bushmaster Predator (1:8 twist barrel) loves it.

Compressed loads are nothing new and are not limited to any one powder. There are also longer powder drop tubes made for powder throwers to assist in making compressed loads. Give this a read and then give this old thread a read. There are also other threads here on THR that cover compressed loads. I have no clue why you were told what you were told but compressed loads are nothing new nor are they dangerous if you use good loading practices.

Like any load, as mentioned, you work up the load.

Ron

 

[Sky Dog]

This is what my late father told me. He was a "Lifetime Master" in NRA High Power. He competed for 30+ years.....I have always headed his advise. This may have been a margin of safety rule. Thanks for the links.....

 

[gamestalker]

Many of my worked up loads are compressed charges, as per published data. But this is where common sense comes into play with this hobby, in that, compressed charges are indicated in the charge tables. Some of my most accurate and consistent loads are achieved with published compressed loads.

The important aspect here that I've personally seen misunderstood, is a reloader mistaking a compressed charge, as being acceptable with any powder or data not published as such. One such case that comes to mind is a fellow I sold a complete reloading kit to back in the 90's. He mistook compressed charges as something you can safely do with any powder, thus exceeding published maximums by a significant degree. He was a bit on the dense side and managed to misconstrue the information in his Speer reloading manual, in which they discuss compressed charges, that's his story. The very first cartridge he reloaded cost him a beautiful and expensive high powered rifle, and a visit to the ER the result of steel fragments that produced some serious injury to his face and hands. Sheared the bolt lugs clean off, split the chamber open, destroyed a high end Leupold, and also fractured the once beautiful walnut stock. It all could have been avoided, at least for that first box or two, if he would have set aside his pride and allowed me to teach him how to interpret the data, and how to properly use a scale, among other aspects of reloading.

GS

 

[kelbro]

While not dangerous (when loaded to mfrs specs) most compressed loads that I have shot were not the most accurate. I could always find a powder that would net the same accuracy with my desired ~95% fill.

One other consideration for compressed loads is that they can cause the COAL to creep over time if the neck tension is not adequate or you don't use a crimp. This could result in an overpressure situation.

I've done it. Safely. I just prefer not to.

 

[steve4102]

Compressing powder is perfectly acceptable if there is load data to support the charge. There is nothing dangerous about compressing powder.

Compressed loads often times produce the most accurate ammo and are desired by many. Most of my rifle rounds are compressed and even heavily compressed.

Sorry, but your father was mistaken, it is OK/fine/safe to compress powders as long as you follow safe loading practices, start low-workup, stay within published data.

Take a look at Hodgdon data for the 30-06, plenty of Safe loads using compressed charges.

http://data.hodgdon.com/cartridge_load.asp

 

[jim243]

I have always been told never compress powder in reloading.

Not a recommended practice, but sometimes you have no other choice. Because of the length of the bullet and the OAL it has to be set at, you are diminishing the available space in the case for powder. The less space the higher the pressure when the round goes off.

The (c) in your reloading manual is a warning that the publisher of the table has put in to tell you to be careful when using that load. The main concern is that the bullet will start creeping out of the case when the round is finished over time. Yes the powder can push the bullet out of spec if the neck tension is not tight or the crimp too light. The best way to check for this is to load a round and let it sit for 24 to 48 hours and then remeasure the OAL of that round , if it has grown then you have a problem, if not then you are OK.

Generally compressed loads are a max load for that powder and bullet type, max loads are not the most accurate and are generally considered only for hunting loads when you need the most power at a long range to take an animal on the first shot.

The choice to use or not use compressed loads rests with the person reloading, usually a 0.2 or 0.5 grain lighter load will make very little difference and in many cases will be more accurate.

The choice is yours, but for safety reasons, I do not do compressed charges. I back off a 1/2 grain and then it is no longer a compressed charge.
Jim

 

[Comrade Mike]

No danger with compressed loads, just follow good practices. Some guns like compressed loads, some don't. Milage will vary as always.

 

[dagger dog]

There are exceptions to every rule, Don't compress TrailBoss powder.

 

[M1key]

...or Bullseye

M

 

[frankge]

In like the crunch stick powder makes lol

 

[Sky Dog]

I guess I'll drop back and look at the big picture here.....What have I got to gain? Possibly a miniscule amount of range and accuracy. What have I got to loose? Possibly have my face blown off.....Hmmm, tough choice.

 

[Comrade Mike]

I guess I'll drop back and look at the big picture here.....What have I got to gain? Possibly a miniscule amount of range and accuracy. What have I got to loose? Possibly have my face blown off.....Hmmm, tough choice.

Well that's true of reloading in general. Factory ammo shoots great for most people, If we just settled for shooting "well enough" we wouldn't take the risks of rolling our own now would we

 

[steve4102]

I guess I'll drop back and look at the big picture here.....What have I got to gain? Possibly a miniscule amount of range and accuracy. What have I got to loose? Possibly have my face blown off.....Hmmm, tough choice

Please explain how compressing powder is going to "blow your face off"?

Hodgdon along with every other manual would not publish compressed loads if they were dangerous and going to "Blow up".

Sorry, but your father was mistaken and so are you.

 

[morcey2]

There are powders that don't take well to being compressed such as trail boss or bullseye, as has been already been mentioned.

There are powders that don't take well to _not_ being compressed. Black powder is the most obvious (and slightly irrelevant), but many slow powders burn erratically if there is much free air space in the case.

I've heard more than one person say that compressing any powder is dangerous, but most of those go back to early powders when even the slowest powder was in the 3031 to 4895 speed range. In 30-06 specifically, compressing 3031-range powders is an accident waiting to happen. Pressures will simply be too high. Compressing 4350 is standard and compressing 4831-range powders is pretty much a necessity. Ball powders usually fill the case better than stick powders without needing compressing. Same with short-cut stick powders. My grandpa's load was enough IMR 4350 to fill the case to the base of the neck and seat the 150 grain spitzer bullet. I don't know what the weight on the powder was, but he took grundles of deer with it. Do I do it that way? No, but my 30-06 load is 59 grains of H4350 pushing a 165 grain Speer SPBT at 2900 fps out of the same 1903 sporter that my grandpa used. It's very slightly compressed, but not much.

Depending on the powder you choose, you're severely short-changing yourself by not considering compressed loads.

Another advantage of compressed loads? No worries about position sensitivity.

Also, I'm specifically talking about rifle loading since I don't load pistol at the moment.

Matt

 

[Sky Dog]

I think Morcey answers my question best. It depends on the powder. Dad shot 30 06 and .300 HH Mag competitively after WWII through the early 60's.
He was very good at it. I'm not sure of all the powders he used back then, but he taught me on Bullseye, IMR 4895, 2400 and Unique. Granted that none of the manufacturers would supply dangerous loads, it appears some can be compressed. Of course common sense dictates. Dad's philosophy was probably a rule of thumb just to keep his kid from doing something stupid. He passed away 2 years ago so I can't question his authority, but in all firearm matters he has always been 100% correct.

 

[steve4102]

Currently I use 69 gr. SMK's w/ 25 gr of varget. My
Bushmaster Predator (1:8 twist barrel) loves it.

Your load of 25gr is about 105-110% load density, a compressed load. See how nice they work.

 

[Sky Dog]

Sure do Steve! That's what started this whole thread rollin'. I've been reloading off and on for about 30+ years. Been doing .223 for about 6
months. Varget is a new powder for me as well. That's why I'm asking

 

[rodregier]

This is *not* load recommendations, but a general discussion on powder selection trends:

In cartridges like .223 Rem and .308 Win, Varget tends to be volume-limited. This means max loads will often result in a compressed charge of Varget for those cases.

Many other suitable powders will be pressure-limited, which means there will be airspace left in the case with a seated bullet even with a maximum charge loaded.

The ideal situation would be a load that generates the desired velocity within safe operating pressures and occupies say 95% of the available powder space.

Using a long drop tube or vibrating the charged cases to pack the powder into a more compact configuration before bullet seating can help with powder charges that would otherwise be compressed. Of course, if you're trying to also load with a progressive press, such aids will impede quick workflows :-(

I gave up on Varget for .223 Rem for just those reasons, I wanted to load those cartridges on a progressive press. I've switched to another powder that leaves a tiny amount of remaining airspace when simply dropped from a volumetric powder measure.

Forster sell a drop-tube funnel combo, which is what I have moved to when using Varget for .308 Win. The loads I'm using in .308 Win are compressed w/o shuffle/packing via drop-tube or vibration , but are under 100% density *with* shuffle/packing before bullet seating.

http://www.forsterproducts.com/catalog.asp?prodid=700677

Other retailers handle Forster too.

Powder vibration:

When using a loading block with a single-stage press, simply fill the cases with metered powder normally. When you have a full loading block, use a second loading block over the open case mouths to make a sandwich (holes against case mouths). Wrap several spaced rubber bands around the sandwich to hold the pieces together. Press all 4 narrow edges of the sandwich (any sequence) against a running vibratory case cleaner, say 30 seconds per side. Presto! Gently compacted powder charges without messing with a drop tube.

 

[GLShooter]

One other one you never compress is H335. Straight from the Hodgdon techs.

Greg

 

[steve4102]

One other one you never compress is H335. Straight from the Hodgdon techs.

Why? Other than is is a ball powder. According to the Hodgdon Tech, what is special about compressing 335?

I can tell you that Hodgdon has more than a few 335 loads that are indeed compressed. They may not list a (C) on their load data page, but the charge is indeed compressed.

Example: Max load of 335 (31.5gr) in the 7.62x39, damn near overflows the case.

 

[GLShooter]

Yet when you talk to them they strongly suggest to not compress the H335 as it is a ball powder. Apparently it breaks down the coating/ball combination and may alter the burning rates significantly.

Greg

 

[rskent]

Sky Dog - I have been using Varget for 223 for quite a while. My load for 77 SMK's is compressed. No problem at all. The load
I use most of the time is 69 SMK over 24.5 grains of Varget in Winchester brass. Its not compressed and is pretty soft shooting.

 

[rodregier]

The Ball and Spherical powders are coated with a burning deterrent, which pushes the pressure curve a bit further down the barrel. As GLSHOOTER noted, compression of that powder likely alters the coating and therefore the pressure curve.

Winchester's loading booklets warned about compression too.