custom barrel for cast boolits

[jbunny]

my bud and i plan on getting a custom barrel in 44 cal which we will chamber
for 44 mag. we will be use mainly cast bullets of 240 gr and this barrel maker
has gain twist capabilitys. old time calbers had deep rifleing. was this because
of black powder??? what twist should i ask for? and what kind of rifleing.
thanks
jb

[deltaenterprizes]

Try posting this in the gunsmithing section.

[beagle]

Normally a 1-26 twist will stabilize .44 bullets from about 200 - 320 grains and I'd go for cut rifling as opposed to micro groove.

I made up a 1-18 twist .44 Mag one time and it stabiled heavy bullets just fine but was too fast for lighter bullets so don't get too fast.

Years ago, Felix and I corresponded all winter on this subject and measured lengths and diameters of bullets and ran Greenhill formulas and modified Greenhill formulas all winter and the ultimate twist was 1 in 25.something./beagle

[JIMinPHX]

Geeze, a custom barrel for cast boolits??? I usually make custom cast boolits to fit a particular barrel. ;-)

that aside,
beagle, you have me confused. "cut rifling as opposed to micro groove"??? I thought that cut rifling was an option as opposed to things like button rifling or hammer/mandrel rifling & microgroove was an option as opposed to something like Ballard or progressive rifling. Am I missing something here? You usually have nothing but top shelf information, so seeing something like that from you really makes me curious.

[jbunny]

Normally a 1-26 twist will stabilize .44 bullets from about 200 - 320 grains and I'd go for cut rifling as opposed to micro groove.

I made up a 1-18 twist .44 Mag one time and it stabiled heavy bullets just fine but was too fast for lighter bullets so don't get too fast.

Years ago, Felix and I corresponded all winter on this subject and measured lengths and diameters of bullets and ran Greenhill formulas and modified Greenhill formulas all winter and the ultimate twist was 1 in 25.something./beagle
thanks beagle. my bud has 3 old swedish rem rolling blocks in 50-70 cal 2 of these have the hex bore and the other one has reg deep rifleing. he also has a 45-70
barrel on a martini action and this he chambered in 45 colt . he shoots straight soft
lead bullets in all his rifles around 1100fps and tumble lubed only. they are not long
range but he shoots out to 150 meters. i have prety well settled on 1-26 twist.
over the years there has been quite a controversy on rifleing type. some say the
grouves should be 1.5 times the land width, ect ect. i have ruled out gain twist.
i'm leaning torwards the kiss principle. pure lead, no GC, no paper patching.
we have settled on 44 mag. from what i gather, a pure lead bullet at 1200fps
in a good bore will shoot accurately whithout leading. this is our goal. he has
put deer in his freezer 2 years in a row with these pure lead bullets. there has
to be somebody on this list that can shed some light on what type of rifleing
would work the best. to the mods on this list, if this is in the wrong place sorry,
please move it.
thanks jb

[leftiye]

The reason micro groove rifling causes problems is that it is too shallow. It is only 2 -3 thou deep. It can and has and is made to work, but either button or cut rifling .004" deep holds the lead better. Harder lead probly helps shallow rifling to work better. If you're going to hold velocities down to 1100 fps you might have problems with heavy boolits stabilizing at 1 in 26 inch twist rate - my guess. 45-70s run 1 in 22, and faster at about those velocities in BPCR long range guns for 500 grain vicinity boolit weights - down to 1 in 18.

[runfiverun]

i'd shoot for the .004-.005 rifling height also, you can always add some tin to the mix to help.
40-1 was what win used in it's 45 colt factory offerings for ever and ever and still might.
smoothness of the finished bbl will help immensely also.