Missouri Bullet 44 Magnum 200 Grain - leading with 9 grains of Unique

[Larry Gibson]

Doh......

Larry Gibson

[waco]

Your cylinder is acting as a multi port sizing die at this point. Pretty typical really, they are made for shooting factory j words which are .429" and .430" at the largest.

To shoot cast effectively, the boolit needs to be .001" to .002" larger than groove diameter of the bore which a .431" or .432" would easily accomplish, your barrel has 5 lands and grooves which makes it hard to mic a slug without a special V block or a comparator, but suffice it to say it is not larger than .430" so either one of the cast boolit diameters I suggested would work, then the cylinder throats need to be .0005" to .001" larger than boolit diameter so as to not size the boolit down upon firing, which is what's going on now.

I would suggest reaming cylinder throats to .4315"~.4318" and having them all within .0002" of each other would then allow you to use .431" boolits and would actually present them to the bore at advertised diameter, not throat diameter which in this case is currently not large enough to overcome the root cause of the problem, that being poor boolit fitment in the bore.

When you get your .431" samples, see if they will go into the cylinder throats with finger pressure.

So what is the best way to address thread choke in a 29-5?

[mmesa005]

Sorry for the delay of reporting back to the group regarding latest results of shooting 200 grain cast with 9 grains of Unique. After having dental surgery I needed to take several days off to recoup. After that I reloaded the 200 grain cast and tumbled them with liquid X-Lox. No leading after shooting a box of 100!

Forum member "Thumbcocker" was kind enough to send me some of his 240 grain beauties. Unfortunately I will have to try them at my next range trip as I failed to grab the box with those reloads As I am traveling on business next week I will have to report back on those in @ 1.5 - 2 weeks.

Steven

I finally made it to the range today. I fired several rounds of Missouri 200 grain tumble lubed in alox. Zero leading, very good accuracy. Tried the 240's provided by Thumbcocker and unfortunately got leading almost immediately😑

Thanks again for all the help and especially to Thumbcocker for sending me the 240's.

[Thumbcocker]

Darn. Sorry they didn't work for you. For those interested H&G 504 clone sized .431 in a Star and lubed with Ben's Red.

[Uncle Dave]

For What It's Worth - The throats on a S&W original model 29 I just measured recently were all at .431-.4315. Research on this site has me less worried about bore size and more about throats and maximizing on the fit there. No issues so far with factory ammo. Testing of appropriate sized rounds will be my true test. I'm going to try HTC route on pistol and PC on rifle. Have yet to drop a CB yet but first molds - MP - shipped today. Awesome info on here and plenty more for me to learn.