BPCR basics

[AtlLaw]

Thinking about my 45/120 project and BP loads.  I am under the general impression that jacketed bullets do not do as well, accuracy wise, as cast bullets do with BP.  Assuming that is correct, how do Gas Checked cast bullets do with BP?   

[Hairtrigger]

My Browning BPC shoots jacketed bullets very well. It will shoot cast bullets almost as accurately but seems to be more work... since I do not compete I stick with jackets

[Graybeard]

Iffen yer gonna load real BP then shoot soft as in almost pure lead (say 20:1 or 30:1) plain base bullets. You'll need lots of lube and it can't be just any lube it needs to be proper for BP shooting to keep the foulding soft. Not the same kinda stuff ya use normally with smokeless.

[boommer]

BP you don't use gas checks unless you shooting a slug of 350 gr or so and then you wont have enough lube capacity on your bullet for bp to keep your fouling soft. If your getting into BPC 45-120 a hard one to learn on 45-70 or 45-90 is a better choice. The bullets that you should be using will be 500-550- grain for long range shooting and they need BP lube it is different than smokeless lube it will gum up your barrel. The velocity you gain with a 45-120 is not great over a 45-90 and if you Duplex the 45-90 it,s faster I personally wouldn't do that with a 45-120 unless it was old school with 4f powder. Bullets need to be soft and flat base like Greybeard said. Swiss powder is the hottest powder out there but in the Bp world we also like others.I like 1.5 Swiss but their are alot of GOEX FANS TOO!! I can tell you this smokeless you can load to the manual and get decent groups but black there is no manual!  because you load powder by volume not grains and grains volume in black is not a exact science because you take 4 different measure device's and you come up with a different volume on each. In black it comes down to this, bullet design, volume of powder compress powder (how much) if none , no air space, cartridge length in lever gun crimp! or single shot taper crimp bullet up to lands? card, grease cookie ,drop tube all changes volume of powder and more and makes the difference's between groups and pattern. hope this helps!     

[AtlLaw]

thanx!!  Good stuff there, just what I wanted to know.

[Ray Newman]

You can shoot BP & jacketed bullets.

The main bug-a-boo is removing the copper fouling so you can remove the residual BP fouling. If you don't, the BP fouling under the copper will attack the bore. A few years ago, there was a thread over on the Shiloh board 'bout BP & jacketed bullets. Kirk, one of the Shiloh-Sharps owners, said that he band sawed a few barrels in half lengthwise hat had been shot w/ BP & jacketed bullets. & the barrels showed signs of pitting under the copper.

You also want to remove all the copper if you shoot lead; otherwise the copper will attract the lead & build up. Same w/ shooting lead bullets, you need to scrupulously clean to bore so as not to attract copper fouling. 

Now some will say that shooting copper/jacketed bullets will clean out the bore of all lead. About 20 years ago, the American Rifleman had an article about this practice. Test results showed that all shooting jacketed did was evenly spread the lead out in the bore.

As for lead bullets w/ a .45-120, you just might need a fairly hard bullet, depending upon the nose design. I shoot a 14 lbs .45-2 7/8" (AKA .45-110) Sharps-Borchardt w/ a 545 grain Buffalo Arms Creedmoor bullet. Shoots very well w/ iron sights (2 MOA) w/ a 20:1 alloy (20 lbs of lead & 1 lb of tin) bullet, but I probably should go w/ a 15:1 or 16:1 alloy. W/ too soft  an alloy, the nose will slump & destroy accuracy. That alloy & bullet does shoot well in my 23 lbs. .45-2.4" (AKA .45-90) Sharps.   Kenny Wasserburger & others over on the Shiloh board who regularly shoot the .45-2 7/8"  up 1000 yds. found out years ago that alloy & bullet design are critical to accuracy.

You will more than likely need to try a few different nose designs & bullet weights to find what will shoot well.

As an aside, the ol' Borchardt .45-2 7/8" is a 'hoot to  shoot', but even @ 14 lbs & 545 grain bullet, it does get tiring after about 35-40 rounds w/ 90 or 95 grains of GOEX Fg. I did shoot a 15 lbs .45-120  loaded w/ GOEX Cartridge &  after 10-12 rounds w/ Postell style bullet, it was no fun.

There is an on-line BP reloading manual @:

Adobe format --
http://www.ssbpcrc.co.uk/Resources/Introduction%20to%20BPCR%20Loading.pdf

Same document, but in MS WORD format --
http://www.ssbpcrc.co.uk/Resources/Introduction%20to%20BPCR%20Loading.doc

If you or others are thinking about casting your own bullets:
http://www.longrangebpcr.com/8Phases.htm

SPG , Black Magic,& DGL lube are good BP lubes. I've lubed w/ SPG since just about the time it 1st hit the market. They are available form Buffalo Arms. As one poster mentioned, a BP compatible lube is necessary. Its purpose is to keep the residual BP fouling soft  & prevent leading. If the fouling builds up &/or become hard, accuracy will go out the window.

W/ a .45-120, don't be surprised if you need to  wipe & dry the bore after each shot. The bigger the cartridge capacity, the more residual fouling you'll need to control. Been there; done that w/ my .45-2 7/8"....

What yardage are you planning to shoot the .45-120 @?  Do you know the twist of the barrel? Twist  is also a factor is shooting an "accurate"  bullet. Some faster twist barrels will not stabilize the lighter bullets.

As for powder, I would start out w/ GOEX FFg or Fg. Anything finer will increase pressure, velocity, & recoil. Often times w/ BP your most accurate load is not the fastest. Primers are another often overlooked factor w/ BP & accuracy. W/ straight BP my rifles will hover around 2.0 MOA  w/ CCI BR primers. 1-1.5 MOA target performance w/ a Duplex load & WLR primers. As will all things BP, you are going to need to experiment as what will perform the best.

[Lead pot]

Your right on Ray. Good post.
It's not a good idea to shoot copper over lead or lead over copper fouled bore.
I have done a lot of work with bullet designs and alloys.
One thing that I found is the longer the ogive radius is the more slump the bullet will get.
A .410 diameter bullet will distort more then .458 or .510 diameter bullet.
I was always a believer in soft alloy like 1/30 to 1/40 and they will stand up good if you stay with a short radius bullet nose, like a round nosed bullet or a long elliptical radius with a flat nose. Those bullets also will slump but the slump will be straight  back and not off to the side like the long 2.5 or longer caliber elliptical radius bullet have.
For bullets with the long radius I stay with alloy no softer then 1/20 and the bullet diameter at groove diameter or .001 over groove.
The .40 caliber 1/20 is the softest recovered bullet that still show compression of the ogive. I use a 1/18 alloy with the .410 diameter bullets with a long elliptical radius, and the accuracy improvement shows it.
Here are a few undamaged paper patched recovered bullets with various alloy hardness. the once that are badly wrinkled are 1/35 alloyed. The alloy ranges from 1/14 to 1/35.
All bullets are .45 caliber except #11 is a .50 with 1/25 alloy.
Some are breach seated and some seated deeper in the case then others.
All were shot with black powder. I dont use white powder in my sharps and high walls.


LP

[Ray Newman]

LeadPot: please check your private messages on this board.

[AtlLaw]

Great information Ray!  thanks!