Value of compressing

pt2317 · Post by **pt2317** » Sat Oct 11, 2003 2:17 pm

I have been loaring BP for about 9 months and tried just about everthing that Matthews, Venturino, Garbe and Wolf have printed. Hundreds of rounds! Results have all been poor- 2 to 3 inch groups at 50 yards. My biggest confusion is with compression. If I load 68g in my 45-70 using pouring from the graduated measureing tool or use a 24" drop tube the powder is at 2 different levels in the case. I must still compress to .670 depth inside the case to accommadate the Postell bullet. The Mechanical compression is different but the ultimat results are the same. What am I missing in this whole compression thing.Oh by the way. Found if I did not roll crimp OR taper crimp my groups came down to less than 3/4 inch. Now why would that be?

MikeT · Post by **MikeT** » Sat Oct 11, 2003 8:33 pm

pt2317,
I have a question regarding your "compression" number. Is .670 the final depth of the over powder wad? If so, what is the depth of the wad after just "drop tubing" the powder? If you measure the depth before compressing the powder and subtract that dimension from the .670, that is the compression that is added and the actual number that most people are referring to when they talk about thier particular load and compression. If you are actually compressing the powder .670: back off to about .300 to .400.
Keep on hav'n fun!
MikeT
P.S. don't worry about why something didn't help the group size. Just remember to use what works in your rifle.

pt2317 · Post by **pt2317** » Mon Oct 13, 2003 8:40 pm

Thank yopu for your responce: I ran a test to determine the depth from the lip of the case to the powder for 24" drop tubes or for pouring from the measuring tube through a funnel directly into the case. Results:
Wt, gr by vol 24"Tube Direct pour
50 .720" .635
60 .550 .405
70 .315 .095
AS you would expect the drop tube "compressed" the powder. However, I still needed to use a Wolf compression die to give me .670 depth inside the case in order to seat the bullet. This gives rise to my basic questain: what difference does it make if I compress from .315 to .670 or from .095 to .670 (for the 70gr load). The volume compression is still the same. Are we over doing the "criteria for acurracy"thing and making this all over complicated? Does what we compres FROM have more importance than what we compress totaly?

MikeT · Post by **MikeT** » Mon Oct 13, 2003 9:17 pm

pt2317,
You got me stumped on that one! I don't like to "smash" the powder any more than I have to, so I use a drop tube and a slow trickle into the case. Using this method, I have never had to compress my 40-82 more than .230" to get 85 grains of Cartridge into the case. My bullet uses .388" and I have a .060" poly wad under the bullet, so the powder is actually .448 below the mouth of the case. I have used more compression than that but it just increases the fouling and I get a pattern not a group. Rdnck has told me that .45 calibers take more compression than the .40 cal. I would say that you should load some identical cartrides, only dump and smash to get the bullet in on one load and be extra gentle with the other load and see if the method of compression makes any difference.
Keep on hav'n fun!
MikeT

Redhawk1 · Post by **Redhawk1** » Tue Oct 14, 2003 5:29 am

pt2327, I am in the same boat as you. You will have to watch out if you go up in powder weight and still try to compress the powder to the same depth and to get the bullet seated to the correct depth. I tried to increase my powder in my straight sided paper patch and the case bulged out where I was compressing. I ran it back in the sizing die to get rid of the bulge and it pushed the bullet out and made them hard to chamber. Lee Stone told me that my 64 gr. of Goex FFg was to light. In all the books I read they were using 60 gr. by volume which is about 64.0 gr. by weight. What I have found is, I need to use more of a postell bullet than a round nose bullet so give me more case overall length. I also found the tapered paper patch bullets work better than the straight sided bullets, because I can load them out further. As far as compression. I have tried several different levels and my point of impact did not change. Wad thickness did not affect my point of impact. Also with compression you will crush the powder, you can't stop it. I don't think there is a science to loading black powder, I am sure I can get better groups with what I am using. I have been shooting scoped gun for so long, I just need practice with my open sights. I know this may not have helped but, as I was told the only way to find out what works for you and your gun was to write your own book and shooting time. What works for one guy may not work for you. I found my Sharps in 45-70 likes the 535 gr. postell bullets the best. and I can only load 64 gr. of Goex FFg. Compressed a lot so it chambers easily in my gun. I have it right out to the lands and it will also chamber with fouling present after a blow tube is used. But I have to shoot paper patch for our hunting season, that is the way the proposal was submitted in Delaware to get use to shoot a rifle here. This is a shotgun only State.

Lee Stone · Post by **Lee Stone** » Tue Oct 14, 2003 9:39 am

Redhawk1,

I apologize. I did not mean to imply that your load IS too light. I just meant that it sounded a little light to me. The Lyman #457132 535gr Postell bullet is one I also use in my various .45/70s. I typically charge them with 68 grains of Swiss FFg topped with a card wad and then a wax paper wad to prevent the card wad from sticking to the bullet. Shoots pretty well for me. But for the life of me I cannot remember just how much I am compressing after drop tubing in order to seat the bullet. I have had my compression dies set for a while.

Redhawk1 · Post by **Redhawk1** » Tue Oct 14, 2003 10:37 am

Lee Stone, no apology needed. I just was making reference to what you told me in another post. I wish I could put more powder in the 45-70. I do love my gun a lot but I think I will have to get a 45-110 so I can play with loads even more. I think I am going to sell my. 50BMG and get another Shiloh Sharps. Just seems more particle

pt2317 · Post by **pt2317** » Wed Oct 15, 2003 5:53 pm

I thank you for your time and responce. Interesting that you mention what has proven to be my only accurate load:68gr of FFg, Lyman Postal bullet, o62 wad and compressed to permit chambering, which is about .670 inches inside the case. My efforts with a 405 hollow base bullet with all sorts of powder charges, hence compressions, failed grouping terribly. With all my shooting I have found only heavy, long bullets gave a hint of accuracy. Is this anyone elses findings?

Another idea: When you drop tube, ie 24", the powder compresses in the bottom of the case. When you compress by simply pouring powder in and using a die the powder is predominatly compressed from the top down. Anybody ever see a difference? I have not and I have tried.

Lee Stone · Post by **Lee Stone** » Wed Oct 15, 2003 6:51 pm

The only difference I can see is that when you drop tube the powder granules align themselves with each other better, and thus you get some, I will say compactness rather than compression because there is no pressure being exerted. Then when you do compress with your compression die, you are not having to compress the powder as much because it is already compacted and with the granuals somewhat aligned there would be less crushing of the granuals. I would believe this would contribute to a more even combustion of the powder with a better power curve. I would think this can have a positive influence on accuracy.

Ray Newman · Post by **Ray Newman** » Wed Oct 15, 2003 8:47 pm

Heed Lee Stone's last post....

powderburner · Post by **powderburner** » Fri Oct 17, 2003 9:02 am

the question of compression has always stumped me as well and I would like to commend Lee on his very simple and understandable explanation of droptubing and compressing it makes sense when he says it

thanks Lee

Gunny · Post by **Gunny** » Sun Oct 19, 2003 3:10 am

I am going to make a few assumptions in my response here. Almost every time I do that ( Make Assumptions) I get at least some of it wrong, but here goes.

From the postings in this topic I am "assuming" that some or most of you guys are new to this sport. The topic of compression can be a befuddling mess. I don't believe that it needs to be. Compression should be a simple fact of life when it comes to loading for one of these old smoke poles. And you may, or may not need to compress!!!!! Boy's there's a statement for you. Now what could he mean by that?

Compression and weather you need it or not is completely dependent on what type of powder or more properly what brand of powder you are using. Goex "Seems" to prefer compression, while Swiss does not. And Swiss powder in all of my testing, and that is a lot, prefers little or NO compression.

A couple of years ago Goex was having what some reported as trouble with there powder. Cases of the lots in question where used as fertilizer by people who publicly stated that all Goex powder was junk and not worth shooting at all. This "Bad Powder" was pretty easy to get a hold of as no body wanted to shoot the stuff. I was able to get a case of this powder for a song and wanted to find out for myself weather it was bad powder, or maybe bad loading technque. I started with this "Bad Powder" from the begining with a case full where I could seat a bullet all grooves covered .060 wad etc. etc. etc. And no compression. I worked my way from there. All shots where on paper, and all shots where shot over a chrony. What I found was that this wasn't "bad powder" at all. What it was, was different powder needing to be loaded the way it needed to be loaded. These lots of questionable powder turned out to be a little slower, but at the same time they fouled a little less. The load I ended up with required about .350 of compression and that was after drop tubing. The way I learned ---- How Much Compression------ to use was by proper load testing and letting the powder and the rifle "TELL ME" what they wanted. You can not win this game of BPCR loading by you telling the rifle and components what they want, this will not work!! Period.

The example above I use to show that rumors can and do get started because some folks want to take short cuts, and I am here to tell you there ain't none of those in this game. Goex is good solid powder, it just has to be loaded the way it prefers. I have heard the question " How much compression do I use with this powder or this bullet or this wad or this case? These questions have been asked dozens of times. And someone usually trying to be helpful will give an answer. The way to determine how much or how little compression to use is easy. Start with none, and a set bullet depth or OAL. As you add powder with this set OAL or bullet depth you will have to add compression. Keep good detailed records, somewhere in this load and try your groups will start to shrink. When you have done the very best you can with this, start changing the OAL or bullet depth this will add greatly to your powder capacity. When you change this OAL go back to no compression and work your way up, somewhere in there THE RIFLE AND LOAD COMPONENTS will tell you what is right. Then you get to try neck tension and no neck tension, crimp or loose bullets and the hundred of other things the are variable. And from all of this testing "YOU" the shooter get the best benefit you can. and that is trigger time. There is no substitute for trigger time.

Many of the folks that post here on Kirk's board and severeal of the others BPCR boards know me. And all of those folks know that I am not a "Braggert". I also am not much for a feller having to post his "Bonifides". But I am going to relate this little story. Last year was my first full; year of competeing at BPCR Silhouette. The year befor I only shot 4 shoots and was in "A" class. I was not very happy with this "A" class thing and spent the winter in load work-up and trigger time. The first shoot last year I shot a 27 my best in the 4 shoots the year befor had been a 16. I made "AAA" in the first three shoots last year (It takes three "AAA" scores to move up) I then went on and made "Master Class" in the next 5 shoots. This was not an easy task. I am a retired Marine and had the time to shoot a lot, and I mean a lot. My practice sessions where shot 3 times a week at least, and at each one of those sessions I would shoot a min of 150 shots. With all of that practice and shooting a match every weekend I was getting a lot of trigger time. And that is the key, you will not get better without shooting. And whoever you are "You Can Get Better With Trigger Time".

The loads will come if you develope a good load techinque. Start from the begining and let the rifle and the components tell you!!

Gunny

rdnck · Post by **rdnck** » Sun Oct 19, 2003 5:47 am

Gunny--Amen, brother! That is the most comprehensive, accurate, and informative post about loading for and shooting these rifles I have seen on the internet. Well said indeed. Shoot straight, rdnck.

Post by **Kirk** » Sun Oct 19, 2003 10:47 am

Good morning Gunny, very good post, I hope everyone just starting out in blackpowder can read this. I always enjoy having a seasoned blackpowder shooter write down what he or she does with out leading new people a-stray, like I have seen happen so many times. Keep it up, and thanks. This goes for every one else on this sight that doesn't try to make it a big secret loading black. Thanks again everyone, Kirk

Kenny Wasserburger · Post by **Kenny Wasserburger** » Sun Oct 19, 2003 12:29 pm

Perhaps the best wrote, well thought out post on the subject of compression tha I have ever read.

Kenny Wasserburger