Powder compression question

Trapper-Jack · Post by **Trapper-Jack** » Fri May 14, 2004 11:49 am

I got into this reloading for BPCR last fall. Through my load experiments I havent yet found a real sweet load yet. I read about you guys talking about the amount of powder compression that you are giving to the different powders, Swiss and Goex. My question is are you compressing after loading the powder through a drop tube? Are you even using a drop tube or are you putting the powder in the case and using compression in place of the drop tube?

JAGG · Post by **JAGG** » Fri May 14, 2004 11:55 am

T J ! I use a 36inch trop tube first , then i compress the powder in the case to the base of the bullet and any wads used ! JAGG

Rdurk · Post by **Rdurk** » Fri May 14, 2004 2:05 pm

Trapper. Drop tube first via a 24 inch (or longer) tube. Then compress, as per the needs of the specific powder type and your individual rifle. Goex generally needs compression un to .350 (that's right .. three hundred fifty thousandths of an inch) for optimum performance. At that compression, burns real clean with reported excellent accuracy. Swiss, very different, generally requires little or no compression .. I say generally. Normally 0.010 - 0.040 .. that's only 10 - 40 thousandths. Good shootin.

8iowa · Post by **8iowa** » Fri May 14, 2004 2:45 pm

Trapper:

I place my Lyman 55 Black Powder measure with it's 24 inch drop tube next to my turret press. After expanding the neck, I drop the powder into the case, insert a .030 Walters wad, and then run the case through the compression die in the press. Bullet seating and the taper crimp follow, completing the loading operation. A 36 inch drop tube might have some advantages, but that would probably require me to use a step stool for the long reach. Rather than stand up and sit down numerous times, I usually drop the powder into the whole lot of cases, and place them in a loading block. I can then sit down and compress them all at once.

I'm using GOEX Cartridge BP and compressing .300 in my 40-70ss.

crazeyiven · Post by **crazeyiven** » Sat May 15, 2004 12:28 am

When I first decided to go back to blackpowder I was confused by the compression issue.

As the others here have stated, the drop tube causes the powder to compress. Then, as 8iowa indicated, a compression die is used to further compress the powder.

There are several posts on this site that get into this topic in nice detail. The decimal compression figures come from where the powder level is in the case, after the use of the drop tube and after the wad has been inserted.

The amount of compression used, as noted above, is generally that which will allow the bullet to be seated firmly on top of the powder with the grease grooves covered.

What that compression number is varies based on several factors including powder used, case, caliber, bullet, wad.

And, to add a bit more to the discussion, I believe there is also a post or a link to a post about using vibration instead of the drop tube. If I recall the article correctly, you dump the powder as you would with smokless, put a group in a loading block, then vibrate the block and charged shells for 25-35 seconds. I think the article indicated they had used a vibrator shell cleaner. The vibration needed to be low enough so as not to bounce the powder out of the case.

Buffalo Arms offers the compression plug and die body for several calibers...see below.

http://www.buffaloarms.com/browse.cfm?v ... 150&step=2

I do not want to pass out bad info. If I've misstated anything here, please feel free to jump in...I've relative new to this too and always interested in more info!

Hope this helps.

crazeyiven · Post by **crazeyiven** » Sat May 15, 2004 12:30 am

Trapper-Jack-

Also, welcome to the site. Lots of folks here with great experience AND a willingness to help.

crazeyiven · Post by **crazeyiven** » Sat May 15, 2004 1:09 am

Here is a link to a discussion of compression on this site.

viewtopic.php?p=10518&highlight=#10518

Trapper-Jack · Post by **Trapper-Jack** » Sat May 15, 2004 7:50 am

Thanks alot for the information!! Also thanks for the welcome. As I said befor, I am new to this game and everything that I have read has indicated that better accuracy and consistancy could be achieved with the real BP, but everything that I have done so far I have gotten better with Pyrodex loaded as per the instructions on the Hodgen's site. The real BP that I tried was Goex ffg, fffg and a pound of Kik ffg. The best groups that I got with the Pyrodex was about 2.5 MOA where my groups with the BP was about 3.5 to 4 MOA. It was totally opposite from what everyone else was getting. Very confusing. I'll try loading some more shells using more compression.

TJW · Post by **TJW** » Sun May 16, 2004 7:58 pm

Good evening. this thread might be a good place to ask a related queation I've been having trouble with. I've just loaded my first batches of BPCR and am unsure about bullet seating.

After compressing the powder with a compression die do you adjust the bullet seater so the bullet compresses another .001 or .002? Or must it just touch the wad? Or is it O.K. if there is .002 or .002 air space between the wad and the bullet? I found it very hard to be sure there was no air space and not add any additional compression with the bullet. Would really appreciate hearing how you deal with this. Thanks. TJW

IronSight · Post by **IronSight** » Sun May 16, 2004 8:56 pm

TJW,
I use just enough neck tension to prevent the bullet from falling out. I neck size and neck expand to allow for slightly firm hand seating of the bullet and call it a day. The bullet has to be pushed in straight or damage to the base could occur. If the brass expands while the bullet is being pushed in, there's too much neck tension.
You don't say, but if your sizing the brass to the point where you need a bullet seating die and can't feel when the bullet bottoms out you have to be careful the soft lead bullets don't get distorted, especially the base and nose.
If your after tight neck tension (hunting loads?), you might want to consider sizing to allow hand seating and use a taper crimp.

rdnck · Post by **rdnck** » Sun May 16, 2004 9:02 pm

TJW--Do not compress the powder another .001 to .002 with the bullet. You will swell the nose of the bullet, in all likelihood.

Here is how I check to insure that the bullet touches the wad. Place a wad cut from wax paper on top of the powder, or on top of the wad you are using. Carefully measure the nose diameter of the bullet you intend to seat, and write it down. Seat the bullet. Now re-measure the nose diameter of the bullet. If it is the same, pull the bullet and see if the wax paper wad is stuck to the bullet base. If it isn't, measure another bullet and seat it just a slight bit deeper. Check the diameter again. What you are looking for is a seating adjustment that causes the nose of the bullet to swell a half thousandth or so. When you find this, back off on the seating stem ever so slightly. A properly adjusted seating die will seat the bullet without swelling the nose, and when you pull the bullet, the wax paper wad will be stuck to the base of the bullet. Works for me. Shoot straight, rdnck.

Chairman

Caddo Lake Chapter
FES

Ken Hartlein · Post by **Ken Hartlein** » Sun May 16, 2004 11:49 pm

Very good answers here. Here's how I explain the drop tube. I used to cut and sell fire wood. If I just threw the wood in the back of the truck I might get one tree loaded. However if I stacked the wood I could get a tree and an half or maybe even two trees in. Thats what a drop tube does, it stacks the wood (powder) for you. I don't size my cases, I fire form them only and hand seat the bullet right on top of the wads by feel. It works. If I'm making a hunting load I will put a slight crimp on it to make sure it stays in, and sometimes for sihlouette shooting I will put a very slight taper crimp on. So far I can't tell any difference in accuracy.

IronSight · Post by **IronSight** » Mon May 17, 2004 8:50 am

Trapper,
In the beginning, I experimented with Pyrodex and found velocity deviations all over the map. Might of been able to make it work but back then i went with BP mainly cause it was much cheaper and i'll be honest the smoke smelled better.

No doubt, some use Pyrodex and it seems to work for them. Maybe the right lube, etc. can make it work.
The one thing i remember about Pyrodex fouling is it's typically much softer than BP fouling. At first glance, this might sound like a good thing but the softness level and/or buildup seemed to change unpredictably as consecutive rounds were fired. The first few rounds fired OK but then all of a sudden without warning the flyers had their way. Blow tubing just added to the unpredictability of all this.
On the other hand, BP fouling consistency can be controlled much better with the right amount of blow tubing, good lubes and even powder compression.
Thats my experience with and how i remember Pyrodex.

Trapper-Jack · Post by **Trapper-Jack** » Mon May 17, 2004 9:07 pm

IronSight,
I've seen some of what you are talking about. Specifically I will get three or four shots in pretty tight then I begin to get flyers, even with blow tubing. The flyers seem to be wide to the left or right, however they seem to be in the all in about the same elevation. Some of my groups have been about 1.5 inches high but six inches wide at 200 yards. I have found up to this point that with Pyrodex the fouling doesn't seem to be as bad as with BP, however this weekend I did some experimenting with BP an different amounts of compression. I began with Goex fffg, and 70 grains by weight of BP for my 45-70. The 70 grains gave me about .19 of an inch compression. Of the five rounds that I loaded this way, I couldn't get the third one chambered due to the fouling. I loaded five more using 71 grains. This increased the compression by about .025. I then continued loading five rounds increasing the load by one grain for each five round batch. Each round of five resulted in about the same results as for the fouling with varring group sizes, from just over three inches to six inches at 200 yards. Then when I reached .300 inch compression I noticed a change in the sound of the discharge, found that all five rounds chambered easier and the fouling in the barrel after the five rounds was more like I was seeing with the Pyrodex. I could see some light reflection in the barrel and not just a dull black fuzzy bore. I ran out of time to do more testing, but I plan to take up from there and continue on at least through the .350 inch compression that Rdurk was telling me about.
I want to thank everyone that replied to my question. It seems like a good bunch of people here on this site who arent bashful about helping a newby.

IronSight · Post by **IronSight** » Tue May 18, 2004 5:45 am

Trapper,
As i see it, for those of us who have this Black Powder obsession, its in our best interest to help newcomers and get em shooting decent, happy and yes hooked. This is especially true with BPCR with its endless variables and subtleties. I know a couple guys who just gave it up in disgust because of the frustration, i almost did myself. For those beginners who persist against seemingly insurmountable odds, the payoff is big - you'll see.

One other thing i forgot to mention about Pyrodex was compressing the stuff. Pyro granuales and not as consistent as BP and they're also much softer. Throwing Pyro charges by weight and compressing was a real PITA.
IMO i don't believe Pyro was designed to be compressed.

As far as your BP fouling, tried 3F, been there, done that and ended up with 2F so i can't speak for 3F. But if your fouling is bad enough to prevent chambering there's something serious going on. I think your on the right track with increasing compression, just be careful when you get around .4 " all that compression pressure could bulge the case. However, you might also want to concentrate on blowtubing, lubes, primers and double check your case lengths. An extremely short case could also cause chamber fouling.