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View Full Version : Boolit deformation with full loads



Titch
06-24-2012, 03:53 PM
I shot 200 rounds of 49/90 from my RRB on Saturday with the stoutest load I've ever tried. It seemed brilliant! I used Starline cases, large pistol primers and fine b.p. I had a 500 grain boolit from a lee mould in front of it all made from a mix of range scrap and pure lead with a gas check and my own beeswax/paraffin wax/vaseline/olive oil lube mix . When I was casting them I noticed a few of them "broke their backs" or actually broke in two when I was tipping them from the mould. Disregarding those, it all seemed ok, but I was shooting military reactive targets that don't show group sizes. All the targets fell over fine, but can anyone tell me the likelihood of deforming the base of the boolit if I use fine bp in such a large case? Is a gas check really necessary? Are there any pressure dangers associated with using fine bp or is bp pressure so low as not to worry? The rifle itself is an 1872 Scandinavian rrb rebarrelled to 45/90 and has Smokeless proof marks. Thanks. Titch.

bigted
06-24-2012, 04:27 PM
what F designation is the 'fine' bp you are using? also if your mix for the lead boolits is too hard they may just explode when hitting steel like i think your talking about.

unless you are talking about 4f blackpowder...i can be fairly sure that you will never be able to load a load that will go into so much preassure that it will be harmfull to your rifle...[considering that it is checked by a competent gunsmith for sound, tight shootability condition]. i shoot a 45-120 and ive crammed 136 grains of powder [GOEX cartridge powder] in these long cases and compressed enough to seat a 520 grain lyman boolit and all that happened was that i experienced a very sharp pain in the shoulder with every such loaded rounds. in inspection of the cases... i see no such pressure signs such as cratered primer...setback primer...primer flow into the firing pin hole...case stretch...neck strain...enlarged case in front of the web area...these loads are not for the timid i can tell you and yet no over pressure signs to be seen...with the exception of the shooters shoulder.

also the gas check is not necessary with blackpowder shooting as long as the metal mix is held to the fairly soft mix so as to allow the blackpowder to "bump" up the boolit like it does in fine shape.......also the reasson for a gas check is to allow the boolit to be shot at speeds that otherwise would lead the snot outta your barrel with the blowby at the base of the boolit and is only able to be reached with such velocity is with smokless powder... which again if your mix is rite wont happen with blackpowder.

just do NOT fill that larger case full with ANY smokless powder...then you will probably experience a catastrofic event. wont be fun for the shooter or by-standers!

cal50
06-28-2012, 04:19 PM
If they are frosty your too hot.
If the bullets are slumping or bending out of the mold your hold / cool off time could be too short.

I let the mold cool off at least 10 seconds after the sprue freezes up before opening.

Use a veggie or similar wad for the bullet base. Gas check not needed.