Compression of black powder in cartridges. How much is too.....

[prs]

The cartridge with which I am working is 45 Colt, but ingeneral, and also considering the Colt "long" case, how muchcompression is enough? How much is toomuch? How much is too little? Theanswers seem to vary by powder brand, I recall Goex and Elephant"liked" to be squished, but Swiss perhaps not so much.

What have your experiences taught you about this?

prs (PigeonRoost Slim)


I found some goodies in my search, for example this one fromJohn Boy, who may have thought he was posting back to me, but it was another"prs":

"prs,actually the amount of compression is powder dependent for good accuracy. Givethis a read:

the Black Powder Cartridge News -2009 Fall - "Some Black PowderCompression Data" article by Bob Woodfill:
Caliber - 45-70
Lyman 457124
Constant volume of FFg powder used
Compression tested: 0" - 1/8" - 1/4" - 3/8" and 1/2"
Best 3 Shot Groups 100yds ... 5 shot groups were tested also, with the samecompression values except for Goex (1/4") and Schuetzen (1/2")
Goex - 0.62" with 1/8" compression
Goex Express - 0.26" with 1/4" compression
Schuetzen - 0.61" with 1/4" compression
Swiss - 0.56" with 1/2" compression
KIK - 0.65" with 0" compression"

Wow! Any of those are better than I can hope for.

And then, Grapeshot:

"Can Icompress BP in a pistol cartridge too much?

Only if it detonates in the press. Seriously, I loaded a batch of .45 Colt witha WEIGHED charge of 40 grains of 2Fg Goex dropped through a drop tube intoWinchester Cases.

I then used a card wad cut from Soda can cartons and compressed the powder witha compression die so I could seat a .454 Big Lube 250 grain boolit on top ofthe powder and set it off with a CCI 350 Large Pistol Magnum Primer.

Recoil was stiff and the concussion was intense. Have fun and be safe."

That, is very close to where I am, 38gr Shuetzen, .030 card, .28" compression, then PRS454-250-RF (the Big Lube original) pressed gently to the card. This to be shot 2 100 yard off of rest/bags in Marlin 24" Cowboy rifle, if the weather ever cooperates. Changes can be made in next batch of rounds.

Also information in asearch where w30wcf reported compression of about .20" in antiqueWinchester 45 Colt rounds.

prs

[Nobade]

Trying to shoot that original PRS boolit at 100 yards, the amount of compression on your powder isn't going to matter much. There's not much of anything you can do to make that boolit shoot accurately that far away. It works great for up close and personal distances like you encounter in CAS, but 100 yards is really pushing it. For rifle accuracy, the more traditionally shaped boolits like Lyman #454190, lubed with some good lube like Bullshop's NASA, and propelled by good black powder, like Swiss or Old Eynsford, will give the best accuracy and also not have problems with foul-out.

As for compression, I find that between 1/8" to 3/16" works great in pistol cartridges like this. I normally shoot 35 grains of Old "E" FFg in my Marlin 1894CB 45 Colt rifle for cowboy silhouette. Using the #454190, it shoots as good as I can see, or about 1.5 - 2 inches at 100 Yds.

-Nobade

[BrentD]

When you compress so much that the brass swells and the case will not chamber, you have compressed too much. Otherwise, you can always try more. However, I have never found best accuracy with heavy compression using any powder.

Personally, I find very little compression is best for my purposes. Less than 0.1" in a .45-70.

[montana_charlie]

The cartridge with which I am working is 45 Colt, but ingeneral, and also considering the Colt "long" case, how much compression is enough? How much is too much? How much is too little? The answers seem to vary by powder brand, I recall Goex and Elephant"liked" to be squished, but Swiss perhaps not so much.

The information you read to get those differences were almost certainly written about rifle cartridge loading.

40 grains of BP should be about right in the .45 Colt.
If a little bit of compression is required to get that much under the bullet, you should be all right.

CM

[Don McDowell]

That, is very close to where I am, 38gr Shuetzen, .030 card, .28" compression, then PRS454-250-RF (the Big Lube original) pressed gently to the card. This to be shot 2 100 yard off of rest/bags in Marlin 24" Cowboy rifle, if the weather ever cooperates. Changes can be made in next batch of rounds.

When using Schuetzen powder I found that no compression worked best in all the cartridges. Something around 29 grs of 2f with a .30 wad under a traditional 250 gr 45 colt bullet (mostly the Remington bulk bullets) worked the best. 37 grs of Goex 3f was also good with the same bullets

[JeffinNZ]

I compress Swiss 1.5Fg 0.35 inch in my .38/303 and Swiss 3Fg 0.25 in my Cadet loads. Both shoot GREAT.

[cajun shooter]

I have found the same results as Nobade when it came to shooting all of the Big Lube bullets at anything past 50 yards. Had plenty of tumbling type of target hits. I think Dick went to far with a lot of the molds he has made by Lee. They are for the most part, too heavy with lube.
If you take an original 44WCF bullet out of the case, you will be looking at a bullet that was very close to what the Lyman 427098 started out as. They rounded the driving bands and made the lube grooves too shallow for shooting BP. I designed a bullet with Tom at accurate molds, 43-210B which shoots well out to 300 yards with BP and NASA lube. My friend 30wcf aka 44wcf designed the 43-215C which does well in his longer 24"bbl Marlin rifle. My point being that you don't need nor want the huge lube grooves for accuracy if you use a good lube. The compression of 45 Colt cases with BP loading is also not going to make a huge difference in your loads. A standard load of 35 grains will be about the same as your compressed load. You also don't need to use a over the powder wad. They were not loaded that way in 1873 and don't need it today. I had some 45 Colt balloon head cases that accepted the 40 gr. load but I could not tell any difference in them and my normal 35 gr. loads. I don't understand why you are taking rifle loading steps and applying them to a pistol cartridge. It's still a pistol cartridge regardless of the type of gun it's fired in.
If you want more Umph, then use FFF in your loads. Take Care David

[prs]

Hi Cajun! I will attempt to copy your post here and then break into it with comments. I hope I do not create a mess.

I have found the same results as Nobade when it came to shooting all of the Big Lube bullets at anything past 50 yards. Had plenty of tumbling type of target hits. I think Dick went to far with a lot of the molds he has made by Lee. They are for the most part, too heavy with lube. prs sez: Its not Dick's fault. It is totally my fault. I designed the original PRS boolit and the spec calls for the lube canyon to be .707% of full outside diameter. They were absolutely designed to be TOO HEAVY WITH LUBE! Bear in mind, back then the common BP we had to work in SASS was Goex or Elephant. 454190 just would not let you shoot a whole weekend match in a 24" rifle without fouling-out. Like you say, 45 COLT was intended exclusively as a pistol round and no need for enough lube to work in rifles. The Mav 44 followed the same spec, just downsized, and the Snakebite adhered to the same ratio (that version is wonderful and not a tumbler at all), as did the Johnston 45 200g version. Not sure if Dick "dickered around" with the lube groove on his others or not.

If you take an original 44WCF bullet out of the case, you will be looking at a bullet that was very close to what the Lyman 427098 started out as. They rounded the driving bands and made the lube grooves too shallow for shooting BP. I designed a bullet with Tom at accurate molds, 43-210B which shoots well out to 300 yards with BP and NASA lube. My friend 30wcf aka 44wcf designed the 43-215C which does well in his longer 24"bbl Marlin rifle. My point being that you don't need nor want the huge lube grooves for accuracy if you use a good lube. Yes, w30wcf is the root of my present quest. He was able to get "decent" longer range performance with my boolit, not stellar, but decent. He took a traditional 44wcf design and had a mold made in 45 incorporating my lube groove, except he reduced the depth of said groove until foul-out with Goex started to be a problem and then increased it just to where the SPG lube supply was adequate for extended use with the somewhat dry Goex. Quite some time back, I received a supply of his boolits to try and I am finally getting "a round tuit". But, I am an action shooter, no bench experience, so I am using my original boolits to learn and practice. Then I will load and shoot his design. I suspect that will be about the extent of my desire to bench shoot, just not my "thing".

The compression of 45 Colt cases with BP loading is also not going to make a huge difference in your loads. A standard load of 35 grains will be about the same as your compressed load. You also don't need to use a over the powder wad. They were not loaded that way in 1873 and don't need it today. I had some 45 Colt balloon head cases that accepted the 40 gr. load but I could not tell any difference in them and my normal 35 gr. loads. I don't understand why you are taking rifle loading steps and applying them to a pistol cartridge. It's still a pistol cartridge regardless of the type of gun it's fired in.
If you want more Umph, then use FFF in your loads. Take Care David

I am trying to load the pistol cartridges like our friend w30wcf did/does. He has been a great help and has given me some guidance on this compression issue too. I really don't care about UMPH, the paper targets are pretty easy to kill, but I figured the RPM imparted by velocity might be a variable in w3wcf's success (probably more talent dominated in his case). The .030" card was used by me because I used an internal sizer with beveled shoulders as a compression die and figured the card would help make a neat job of it and it did.

Thanks for the input, Pard.

prs

[cajun shooter]

You may buy compression dies at Buffalo Arms for 19.95 that have the required flat base. I still don't see any powder coming by a 45 sized stem with a bevel edge though. That is pulled from my mind after loading BP since 1970, actual testing the difference never came about.
John and I are good friends and exchange information all the time. He did long range testing for me with my 44WCF bullet design before I could and helped me develop my loads. His 44wcf rifle is a 24 inch bbl. original Marlin and much better for long range testing than my 18 1/2 inch Uberti model 1873 Winchester reproduction. Later David