Ruger Flattop 44 Special Bore Dimensions

[Two Barrels]

I have a Flattop 44 Special on the way. Loading for the 44 Special will be new for me. I am looking to purchase a mold for this gun. Those of you with these, are you casting at .434 and then sizing down or are your molds dropping at .432?

Any suggestions on a bullet design are welcome. Maybe a 200gr and another around 240-250gr.

I saw there is a group buy about to end and if I jump in, I will need to choose between .432 or .434.

[Thor's Daddy]

.432 should work just fine for a flattop.

[dkf]

You should really slug the throats when you get it to see where you are at. You could just get the .434 and size it down but it is nice to size as little as possible. The NOE 432-224 swc was designed for the .44 special in mind but he only has .432" in stock right now. Mihec has the 434-215 in stock on his site.

[oscarflytyer]

.432. Keith design. slug throats. I really haven't found anything mine wont shoot well. IM and happy to share all my load notes

[oldhenry]

My .44 spec. flat top likes the Lyman #429421. H&G #45 and the Accurate 43-210A. When I ordered the 43-210A I was debating it or the 43-210E......I think either would be a good choice.

You will learn to love that flat top.

Henry

[stubshaft]

Mine likes the H&G 503 clone that Miha made for me. I size to .431".

[Oklahoma Rebel]

I got the noe 432-277 "keith style" but it drops at 434, even with my low antimony soft alloy, so when I size them own to 431, and soon I will have a 430, it almost removes the crimp groove, that was my only disappointment with noe, I thought I might have gotten a 434 by accident, but I checked the inscription on the mold block, and yup, its 432!

[Thumbcocker]

I have one with .434 throats that shoots .431 boolits very well. Go figure.

[Ia.redneck]

Mine has .431 throats and .430 barrel. It's one of my best shooters.
Lyman 429421 and 7.2 of Universal sized .431
yer gonna love it!

[Lloyd Smale]

Ive got two both do there best with 431.

[rintinglen]

Mine shoots lights out with .431 boolits. It is the most accurate 44 special I have ever owned.216202

[shorty500]

Seeing this made me realize I have never checked either of my flattops for dimensions. Since they shoot like crazy with bullets cast from both of my Keith style molds sized at .430 with no leading I guess I won’t bother now either

[Two Barrels]

I appreciate all of the responses. I am going to shoot a couple hundred jacketed bullets first to break in the bore. I’ll then move to .431 cast after that and go from there.

[murf205]

You would do well to order some pin gages to check cylinder throats. Meyer Gage co has singles that they sell for reasonable prices and then you wont have to guess. I bought .428,.429,.430, .431, .432, .434 which covered my needs. You will love that new flat top, mine has .431 throats, but with Ruger revolvers, you need to check.

[murf205]

I just checked Meyer Gage Co, and they sell pin gages for $2.25 each and they will sell them individually. When checking out a new revolver, they eliminate the guess work and you will KNOW what your cylinder throats are.

[DougGuy]

You WILL want to order the gage pins in half thou increments. .001" increments is too coarse for accurately measuring throat diameters. Class Z minus is what you want.

[catboat]

Before you order a mold, you should slug your own pistol’s barrel to gather specific info. You also want to find out if you have “ thread choke” ( aka “ frame choke”), which can give a reduced bore/ groove diameter for the first 1/2” or so. If you do have thread choke ( bore diameter reduction from tight threads in the frame), you may need to fire lap the barrel.

Good article about the Ruger flattop 44 special ( and thread choke).

https://www.gunsamerica.com/blog/ross-seyfried-lipseys-ruger-flattop-44-special-bisley-revolvers/

[MSD MIke]

A friend of mine purchased one recently. We didn't slug the bore but throats measured .432 and that's what we size to with good results.

Mike

[osteodoc08]

Took mine out yesterday. Excellent groups up to 25 yards (3”/5 shots with iron sights) with .431” sized 429421 PC boolits over 16gr 2400. Gave me around 1100 FPS using the LabRadar.

[Cosmic_Charlie]

My 5.5" RBH FT has .430 throats so that is what I size to. No leading and exhibits satisfying off hand accuracy. Just installed a Bowen Classic Arms Rough Country sight on it today. Shot some 240 gr. xtp over 17 gr. of 2400 and got 1315 fps. out of it. I like 4.5 of Tite Group or 7.0 of Unique for everyday fun loads with 240 or 250 gr. boolits. My cast iron 2 cav RCBS 250-K mold drops boolits at .4305 so it is perfect.

[wildwilly501]

When buying the Meyers Pin gauges do you buy directly from Meyer?

[Cosmic_Charlie]

Mine shoots lights out with .431 boolits. It is the most accurate 44 special I have ever owned.216202

What kind of holster is that?

[DougGuy]

When buying the Meyers Pin gauges do you buy directly from Meyer?

Yes. They have a $25 minimum order and ask them for 1st class mail if you have a small order.

[Two Barrels]

I went to the Myer Gage sight yesterday. The single Z Minus pin gages were listed for $3.36/ea for the sizes commonly needed for checking cylinder throats.

[md8232]

You WILL want to order the gage pins in half thou increments. .001" increments is too coarse for accurately measuring throat diameters. Class Z minus is what you want.

Help me understand this. I think you are saying Order .4280, .4285, .4290, etc til I have all that I want. Is this right?

[DougGuy]

I went to the Myer Gage sight yesterday. The single Z Minus pin gages were listed for $3.36/ea for the sizes commonly needed for checking cylinder throats.

This is about right. Smaller ones are cheaper, larger ones are more. I'd rather buy directly from Meyer than MSC or Enco.


Help me understand this. I think you are saying Order .4280, .4285, .4290, etc til I have all that I want. Is this right?

Yep, start with one that is below your smallest throat and work in half thou increments until you get above what you would want throats finished at. .429" to .434" should cover all 44 cylinders except 44-40.