bullet prep for fire lapping

[oley55]

thanks, did a search and found this from Buckshot:

Originally Posted by bigted .....i want to explore the possibilitys of diff diameters with them as they apear to be a fairly easy item to resize with a reamer.
thanks
............You won't be happy with a reamed finish, trust me The actual sizing area in a Lee push through is less then 0.10" wide. Oiled carbide paper on a split dowel in a drill motor will get you where you want to go fairly quickly. That is unless you're wanting to take a .451" out to a .460". Then it'd be a career!

..............Buckshot

[wmitty]

Took a .285" Lee up to .301" for paper patching and yes; it did indeed take a while...

[geargnasher]

MyRedhawk was taking so many rounds that I got impatient and used a q-tip to paint the forcing cone with compound and used prepped bullet to carry it thru. Now it shoot great and never leads. Good Luck and have fun Clint

This works too, I have done it on two revolvers when I didn't want to affect the cylinder throats. I used dead-soft, lubricated slugs "breech seated" into the cylinder throats (flush with the front of the cylinder) and a VERY light charge of powder installed in the cases. The cases were unsized, just reprimed and charged, and were loaded in the gun with the muzzle up so no ring-causing filler or wads were required. Cylinder was removed and compound re-applied to the forcing cone area prior to each shot. Worked like a charm.

Gear

[oley55]

Based on discussions here, I decided to slug everything again with the following results:

cylinder throats which I had previously measured with pin gauges at .4320", actually slugged at: .4326-.4328".
full length, slug pushed out thru the breach: .4301"
barrel slug pushed into roll markings and then backed out thru muzzle: .4303"
muzzle about 1" into barrel then pushed back out: .4301"

I don't understand how I can get larger measurements from the middle of the barrel when that slug is either getting pushed back out the muzzle and all the way thru the breach (thread choke). the slugs are soft slugs from NECO so I doubt spring back could possibly account for this.

Regardless of that oddity, it seems the cylinder throats are a bit large and now question fire lapping at all.

Reading http://www.lasc.us/Fryxell_Book_Chap...roatGroove.htm, quote: "The ideal cylinder mouth diameter is about one half a thousandth over the maximum groove diameter of the barrel. Sometimes it is impossible to achieve this magical combination since the cylinder mouths are occasionally larger than the groove diameter of the barrel. In this case the bullets will need to be sized the same diameter as the cylinder mouths. Extreme cases do exist where the cylinder mouth is as much as .005 larger than the barrel groove diameter. This is an extreme case, but it does happen occasionally. The only thing you can do here is to shoot exceptionally light loads and hard or gas-checked bullets, or resort to jacketed bullets."

I also question sizing bullets to the throat/mouth size as quoted above because my throats are very rough with obvious mill/ream marks. I can only imagine them immediately leading up. I really feel like they should be lapped n polished, but this would only make them even larger.

Unless I'm missing something, with the bullet floating/wallowing from case thru throat and forcing cone before reaching the barrel rifling this 1983 vintage Redhawk may be need to remain a jacketed bullet weapon only.

[DougGuy]

I don't think you will hurt it by firelapping. Nor do I think the throat sizes are an issue. They are just about right for sizing to .432" which many do, myself included. I think you will still have a noticeable improvement by firelapping the choke out. It certainly isn't going to hurt it by proceeding.