SBH Cylinder

[mattd]

My SBH bore is 429. My throats are 431. I use a lee pass thru sizer that I honed to 4315-432. I've shot hundreds of cast thru it, most with leading. Mostly the lee 310 that I had the gas checked milled off for a 270g, the 429244 (a lot without GCs) and a few others. I know I haven't run into this problem before, but the last time I loaded the 429244 w GCs the loaded brass wouldn't fit into 5 of the cylinders. Figured it was non-annealed GCs and have since annealed them. Tonite I loaded the lee 310 bullet, sized in my same sizer, and they won't fit either. Put a dummy together with the 429244 and annealed check and they don't fit either. They aren't even getting to the throat.

Maybe I'm using diff brass with these combos then before, but either way my cylinders are too small for the size bullet I need. I don't think honing/polishing is going to be enough to help. What do I do?

[rintinglen]

Are you sure your brass is full length re-sized? Are you over crimping? Those are the two most common issues to arise, especially if you don't have a dedicated press. Undersized cases will bind, as will those bulged by excessive crimping. Since your sizer and molds haven't changed, those are the most likely culprits.

[Piedmont]

Good points from rintinglen. Mark up some loads with a magic marker and see where it burnishes. If in fact the bullets are too big to chamber that wouldn't be the end of the world. Go to a .431" sizer and if that is too big go to .430". If you have tight chambers you know your loaded rounds are not tipping in the chamber, which is a good thing.

[DougGuy]

You could always send the cylinder and have it sized to the boolit you want to shoot in it. That's what I did with mine, I had 3 different throat diameters, so I used a reamer then a hone to even them out with the largest one, which was perfect for a .432" boolit, now all 6 chamber and shoot the 310 w/GC sized to .432" very nicely. I am getting good groups now with no leading to speak of.

It sounds to me like your throats are just a little tight to chamber the loads you have assembled. It is likely they may not be perfectly round either. The magic marker will tell the tale.

Those boolits that won't chamber, will they go into the cylinder throats from the front before you load them into the cases? If they won't go from the front, they won't go from the back either.

[leftiye]

Either your brass is thicker, or your sizing die has worn and is sizing larger. Your chamber mouths are a good size for your grooves. You shouldn't be getting leading. Your leading could be you shooting too fast, or it could be poor lube. Milling off the gas check with those small lube grooves could also be another problem.

[44man]

Might just be the chamber side of the throats are full of leading. Use a good brush and see if it clears up.

[Larry Gibson]

I've shot hundreds of cast thru it, most with leading.

Clean the chambers really good as 44man suggests especially since you are experiencing a lot of leading or perhaps have been shooting 44 SPLs in the SBH?

I also suggest a change in alloy, in lube and a change in the powder/load used when GCs are not used.

I shoot .429 and .430 sized cast bullet in my Ruger FTBH with .431 throats and my Hawes Western Marshal with .434 throats with excellent accuracy and no leading. Given the .429 groove diameter barrels the .430 sized cast bullets shoot as good or better than cast bullets sized to .431 through .434+.

You might also check the crimping die used. If out of adjustment for the different cases it may be not crimping enough or it may be over crimping and buckling some of the cases. Also have you checked the oal of the cases to make sure they are not too long for the chambers?

Do FL sized cases fully chamber? If they do then the bullets are oversized, the cases are buckled during seating/crimping or the chambers are dirty.

Larry Gibson

[mattd]

it may be not crimping enough

Larry Gibson

Larry hit it on the head. I measured the loaded rounds case mouth and they were bigger then they should have been. I guess my crimp die moved to where it wasn't fully removing the bell. I have a turret set up for 44 and things generally don't move, so maybe I moved that one for some reason. a reminder to always double check things!

as to my leading thats another issue, but alloy is 50/50 pure/ww with 1-2% tin, usually water dropped. had been using 50/50 lube, but have since moved to carnuba red. might be a little hard for this application, but thats whats in the pan right now and i thought i'd give it a try. powder has been anything from 8-12g Unique, low to mid range 296, low to mid #9. loading some Blue dot for this round. have never really gotten to max loads.

after eliminating a lot of other things i have been thinking fire lapping might be next. need to figure out how to slug the chamber and muzzle end and still be able to get the slug out since the frame blocks an easy approach.

[**oneshot**]

For slugging the throat I use a block of wood that fits between the slug and the frame to push the slug. For the muzzle, you will need a hardwood dowel that fits the length of the barrel flush at both ends plus 1/4-1/2 inch. Put the dowel in first then tap the slug in with hardwood block. Push it back out with the dowel.

[DougGuy]

Another way to check the bore for thread constriction, use a plastic or brass jag, patch it really tight into a clean bore. As you push it down the bore, when it gets to the part that's threaded into the frame, if the effort to keep the jag moving doesn't change, the bore isn't constricted. If it gets just a tad bit harder to push, you are feeling a mild constriction. If it stops or gets so hard to push you have to beat it, then there is a really bad constriction which in the worst cases firelapping won't take out, those need to go back to Ruger, they will fix them.

For slugging the bore, I used an egg sinker and ran a screw through it, screwed it into the end of a hardwood dowel. I could then grab the dowel with vise grips and tap the vise grips to get the slug back out of the muzzle. I used a second slug and drove it all the way through to measure how bad the constriction was. This was a .45 barrel which slugged right at .451" until it got to the threads, they measured .4485" so it seriously needed work. I ended up Taylor throating this one but that much was way too much to firelap out without messing with the rest of the barrel, which didn't need any lapping.