Tight Chambering and dirty cases

[geronimo]

When I fire my cases they come out dirty and I can not load another round until I clean the chamber any suggestions. I am shooting a Browning 1885BPCR in 45/70.

[Ray Newman]

Give the details of your load.

My initial reaction is that your load doesn't have complete combustion, & the brass is not expanding to completely seal the chamber. Such a situation may permit the gas & BP residue to blowback into the throat &/or chamber.

[geronimo]

My load is 500grn. postell type bullet 20:1 mix SPG lube  card wad  case full to slight compression, no crimp and seated to 10/1000 from the lands.

[Ray Newman]

Powder charge & granualtion??

[Ray Newman]

I'm not thinking very tonight. Too much time on the John Deere & a little too muchsun.

Besides powder charge--garins-- & granulation, what is the bullet diameter?

[geronimo]

.459 diameter, weight is what ever fills the case i don't weigh the charge i use ffg powder

[Ray Newman]

Your bullet should be  of a large enough dia. to seal the bore upon obturation.

I  am having trouble trying to determine how you measure the  powder charge when you say "weight is what ever fills the case i don't weigh the charge ...."

Do you just scoop the case into the powder, use a muzzleloader measure or what?

Most successful BPCR shooters either weight the individual charge then slowly trickle the powder into case via drop tube, or use some sort of measure to meter the charge, then use the drop tube method.

[The Shrink]

Geronimo

It will also depend on the powder you use.  Goex likes as much as .40" compression, and may give incomplete combustion without it.  Swiss reportedly does not like compression and will shoot fine with little to none.  I fill the cast to the brim using the Lyman 55 measure and drop tube and then compress this enough to deat the bullet, usually around .34".  With the 500 gr. bullet I thumb seat the bullet, crimping enough only to keep the bullet in the case.  

Wayne the Shrink

[RPbump]

Geronimo,  I too have a Browning BPCR in 45-70. The chambers in these guns are very tight with no freebore un like the Browning 40-65 BPCR's. You must use a blow tube between shots or you will not be able to chamber the next round. The number of breaths through the blow tube depends on temperature and humidity, start with 3 or 4 deep breaths. You can make your own blow tube from a 45-70 case or order one from Buffalo Arms. Rbump

[gsharps74]

I have had that problem in the past and had to anneal my brass and it solved the problem.

[geronimo]

Thanks all for your reply's. I use a blow tube with only about 2 breaths I'll try three to four as was suggested. I measure the bullet length to see how far it needs to be seated, then fill the case that point  slightly compressing the load. I will try all the suggestions given. Thank's again all.

[Redhawk1]

I measure my powder by weight now. I took 10 each 60 gr. by volume measurements and weighed each and came up with 63 gr. by weight. I also did it for other volume measurements, I have written down in my BP reloading journal. So now I have a weight I can use every time and have consistency. I use a Lyman BP measure and get the weight close and trickle it to the proper weight. I then pour it down a 30 inch drop tube so powder is uniform. I put a wad over the powder and compress the powder to the proper depth to fit the bullet to the proper over all length. If I  use a grease grove bullet I put a slight crimp just to hold the bullet in place. If I use a paper patch bullet I run the case with the bullet in place in the sizing die, with the de-capper removed, just a little to put a slight squeeze on the bullet but not a lot, just enough to hold bullet in place. Also with the cases, I use fireformed brass that has not been resized. Once I shoot a case in my gun I only de-cap the round with a universal de-caper so not to change the cast as all. I clean and tumble the case and them reload it. That way the case fits your gun and you are extending the life of you brass. Hope this helps