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tking308
06-11-2015, 10:59 AM
Ruger Super Blackhawk, 44 mag. A boolit sized to .431 stops at the throats but can be gently pushed through. Bore is .429. I understand that optimum size would be .001 over bore size but is .002 going to make a huge difference in accuracy? I don't have a .430 die to test and don't want to buy one if I don't need it.

captaint
06-11-2015, 11:23 AM
tking - A gentile push to chamber your .431's should not pose a problem - as long as you don't have to ram them hard. Sounds like you're confusing groove diameter with bore diameter. Very common. It's the groove diameter that matters in your case - and .002 over groove again should be fine. Bore diameter will matter if you're loading bore rider rifle boolits. It's important then. If I were you, I'd go shootin. Please report back. We love to hear success stories !!!

Artful
06-11-2015, 11:25 AM
You should be fine as long as your throat isn't just straight tubed. (you should have a coned section at the end of the barrel that funnels you boolits into the rifling).

I actually prefer my boolits to fit my throats over the 1 or 2 thou over barrel diameter.

tking308
06-11-2015, 11:32 AM
Thanks guys, I've been shooting and I'm looking for better accuracy. 4" groups @ 40 yards from a rest isn't going to cut it. I guess I should have been more clear, the rounds drop straight into the cylinder, no problem. The resistance is when I push just a boolit through. I was checking to make sure the throats weren't undersized. I'm considering lapping the barrel with an LBT kit.

mdi
06-11-2015, 12:15 PM
"Gentle push through", "snug fit", "hard to push through" can mean nothing. They are not measurements (If I was standing next to you then those phrases might make sense, but unless I do it, I have no idea). When working to find correct bullet size, measure! Measure the diameter of the bullet in question with a micrometer. Measure/slug the cylinder throats. Slug the barrel. Measure the barrel slug, and the cylinder slug. Then you'll know what you're working with (not a WAG!). I suggest you start with a bullet the same size as the cylinder throat diameter. As long as this dimension is larger than the groove diameter, you'll be fine...

tking308
06-11-2015, 01:12 PM
"Gentle push through", "snug fit", "hard to push through" can mean nothing. They are not measurements (If I was standing next to you then those phrases might make sense, but unless I do it, I have no idea). When working to find correct bullet size, measure! Measure the diameter of the bullet in question with a micrometer. Measure/slug the cylinder throats. Slug the barrel. Measure the barrel slug, and the cylinder slug. Then you'll know what you're working with (not a WAG!). I suggest you start with a bullet the same size as the cylinder throat diameter. As long as this dimension is larger than the groove diameter, you'll be fine...

Thanks for your input. Others have answered the question to my satisfaction.

MBTcustom
06-11-2015, 01:29 PM
Honestly, I think you've got it by the horns. Getting that perfect fit to the cylinder throats is the hard part sometimes, and you've got that down pat.
Now there may be some thread choke in your barrel which the lapping bullets would take care of, but they may do something to your perfect throats too, so I would try other things first, like try three different alloys, three different lubes, and three different powders.
Just a suggestion.
I've got a Redhawk with the exact same throat size, and I'll be messing with this stuff myself soon.

44man
06-11-2015, 03:22 PM
Groove size is what counts and .429" sounds small for a Ruger. Most run .430" so .431" will be perfect.
I found groove size to .432" is fine as long as you don't use the cylinder throats to size your boolits.
If you are not getting what you want, look at the boolit design, lube and primer. Try a standard primer and see. Go to an LBT WLN or a Lee RNFP. Dump the Keith.

Artful
06-11-2015, 03:56 PM
I pretty happy with my Keith's - my advise is try what you got first.

runfiverun
06-12-2015, 01:20 AM
try what you got.
add some water dropping to the mix and see if results improve.

if things do not improve from just that then look for tight spots.

44man
06-12-2015, 07:17 AM
I got the keith to shoot smaller groups at 50 then I was getting at 25 by making them VERY hard.