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NSP64
05-18-2010, 04:50 PM
Has anyone used a cardbord/cardstock cutout glued/placed under PB design boolits to reduce leading. I have shot the lee 310gr Boolit in my 44mag without a GC and haven't had leading, but I was loading 4227 powder to get 1100 fps. I think the powder acted as a buffer. I was wondering if you used a card stock dics under the boolit, could you load it hotter? Or for that matter cream of wheat filler with unique?

mroliver77
05-18-2010, 08:41 PM
I shoot all PB boolits from my .357mag, .44mag and .45 Colt all Rugers loaded to magnum specs.I do run hard boolits ffor the upper end loads but get no leading. I had some boolits that were too small and leaded but grits over a lesser charge of powder kept the bore clean.
Jay

hoosierlogger
05-18-2010, 08:52 PM
Ok I have been hearing about using fillers. How much do you put in there? Does it need to be full to the case mouth and compressed, or just to the base of the bullet?


sorry for the :hijack: , but I must know.

NSP64
05-20-2010, 10:43 AM
I have a Lee 240gr RN PB mold I have tried to load for my 44mag. I have tried different powders and lubes. Still leads. Same lead make-up(w/w with tin) as I load lee 310 RFN bullets without gas checks @ 1100 fps. So, I cut some 7/16" cardboard discs to place under the boolits. Still leads. Bore is .4295, Chamber mouths .430, Size to .431,????? Since this is a PB design I even tried a gc upside down to act as a gas blocker(took out the chronny):cry:

Pushing the 240 (255 as cast) to 1350 may be just too fast. Leading was in first inch of barrel.

May try PPing

Rex
05-20-2010, 10:59 AM
I've cut styrofoam plugs from meat trays for a .357 , they don't work for me.
Rex

Bass Ackward
05-20-2010, 11:18 AM
Bore is .4295, Chamber mouths .430, Size to .431,????? Since this is a PB design I even tried a gc upside down to act as a gas blocker(took out the chronny):cry:

Pushing the 240 (255 as cast) to 1350 may be just too fast. Leading was in first inch of barrel.



Great measurements, but it sounds to me like the slug is being delayed from a barrel or alignment problem of sorts. Sometimes rifling leade angles established by the forcing cones can cause problems like this. Especially if you are displacing a lot of lead like with wide land, S&W rifling or tall Ruger rifling. My new Bisley 44 Sp has a .416 bore and .430 groove. That's .007 tall rifling. It's OK for soft lead, but will hold up a hard bullet enough that pressure raises and it leads at HV. So I shoot 20-1 at 1200 and 28 BHN at 550 till it breaks in.

I would look in the cone for hints from impact smoothing. You should be able to see this with the eye after about 300 rounds.

Did the reverse GC stop the leading though? Normally I would tell you to harden and change lube, but you have been around long enough to have read that a thousand times.

Stuff like this is why I simply don't shoot PB anymore until the gun has broken in from 2000 rounds or I do identify that I have a problem and fire lap it. Same process just that one is faster. You can rush the jump to PB with a new gun.

And as for wads, you can buy cork ones to try of various thickness. I use them for fire lapping when the pressure is too low to seal, but I don't want to lap with a big bullet. I think mine are .060.

BerdanIII
05-20-2010, 12:59 PM
There's an article in the latest Fouling Shot (March-April?) on using gas checks cut from OJ cartons. The blanks are cut with a punch mounted in a lubrisizer. They are then formed in the lubrisizer with an undersized punch to get (and retain) the cup shape and are loaded inverted (cup side down) on the powder charge. The author found that the size of the forming punch was critical to blanks taking and maintaining the gas check shape. I'll get the actual number.

Edit: The gas checks are placed in the neck of the case (.308 WCF, .30-'06; can't tell which) so the boolit base sits on them. For .30 cal. checks, the blanks werre punched out with a .38-55 punch of 0.390" diameter and formed with a 0.285" sizing die and .25 cal. nose punch. The 0.035" diameter difference was critical to the checks maintaining their shape.